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_H 40 #define __ATT_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 // custom BTstack error codes 52 #define ATT_ERROR_HCI_DISCONNECT_RECEIVED 0x1f 53 54 // custom BTstack ATT error codes 55 #define ATT_ERROR_DATA_MISMATCH 0x7e 56 #define ATT_ERROR_TIMEOUT 0x7F 57 #define ATT_ERROR_WRITE_RESPONSE_PENDING 0x100 58 59 // custom BTstack ATT Response Pending for att_read_callback 60 #define ATT_READ_RESPONSE_PENDING 0xffff 61 62 // internally used to signal write response pending 63 #define ATT_INTERNAL_WRITE_RESPONSE_PENDING 0xfffe 64 65 typedef struct att_connection { 66 hci_con_handle_t con_handle; 67 uint16_t mtu; // initialized to ATT_DEFAULT_MTU (23), negotiated during MTU exchange 68 uint16_t max_mtu; // local maximal L2CAP_MTU, set to l2cap_max_le_mtu() 69 uint8_t encryption_key_size; 70 uint8_t authenticated; 71 uint8_t authorized; 72 } att_connection_t; 73 74 // ATT Client Read Callback for Dynamic Data 75 // - if buffer == NULL, don't copy data, just return size of value 76 // - if buffer != NULL, copy data and return number bytes copied 77 // If ENABLE_ATT_DELAYED_READ_RESPONSE is defined, you may return ATT_READ_RESPONSE_PENDING if data isn't available yet 78 // @param con_handle of hci le connection 79 // @param attribute_handle to be read 80 // @param offset defines start of attribute value 81 // @param buffer 82 // @param buffer_size 83 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); 84 85 // ATT Client Write Callback for Dynamic Data 86 // @param con_handle of hci le connection 87 // @param attribute_handle to be written 88 // @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 89 // @param offset into the value - used for queued writes and long attributes 90 // @param buffer 91 // @param buffer_size 92 // @param signature used for signed write commmands 93 // @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 94 // 95 // Each Prepared Write Request triggers a callback with transaction mode ATT_TRANSACTION_MODE_ACTIVE. 96 // 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. 97 // 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. 98 // Otherwise, all callbacks will be called with ATT_TRANSACTION_MODE_CANCEL. 99 // 100 // If the additional validation step is not needed, just return 0 for all callbacks with transaction mode ATT_TRANSACTION_MODE_VALIDATE. 101 // 102 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); 103 104 // Read & Write Callbacks for handle range 105 typedef struct att_service_handler { 106 btstack_linked_item_t * item; 107 uint16_t start_handle; 108 uint16_t end_handle; 109 att_read_callback_t read_callback; 110 att_write_callback_t write_callback; 111 btstack_packet_handler_t packet_handler; 112 } att_service_handler_t; 113 114 // MARK: ATT Operations 115 116 /* 117 * @brief setup ATT database 118 */ 119 void att_set_db(uint8_t const * db); 120 121 /* 122 * @brief set callback for read of dynamic attributes 123 * @param callback 124 */ 125 void att_set_read_callback(att_read_callback_t callback); 126 127 /* 128 * @brief set callback for write of dynamic attributes 129 * @param callback 130 */ 131 void att_set_write_callback(att_write_callback_t callback); 132 133 /* 134 * @brief debug helper, dump ATT database to stdout using log_info 135 */ 136 void att_dump_attributes(void); 137 138 /* 139 * @brief process ATT request against database and put response into response buffer 140 * @param att_connection used for mtu and security properties 141 * @param request_buffer, request_len: ATT request from clinet 142 * @param response_buffer for result 143 * @returns len of data in response buffer. 0 = no response, 144 * ATT_READ_RESPONSE_PENDING if it was returned at least once for dynamic data (requires ENABLE_ATT_DELAYED_READ_RESPONSE) 145 */ 146 uint16_t att_handle_request(att_connection_t * att_connection, 147 uint8_t * request_buffer, 148 uint16_t request_len, 149 uint8_t * response_buffer); 150 151 /* 152 * @brief setup value notification in response buffer for a given handle and value 153 * @param att_connection 154 * @param attribute_handle 155 * @param value 156 * @param value_len 157 * @param response_buffer for notification 158 */ 159 uint16_t att_prepare_handle_value_notification(att_connection_t * att_connection, 160 uint16_t attribute_handle, 161 const uint8_t *value, 162 uint16_t value_len, 163 uint8_t * response_buffer); 164 165 /* 166 * @brief setup value indication in response buffer for a given handle and value 167 * @param att_connection 168 * @param attribute_handle 169 * @param value 170 * @param value_len 171 * @param response_buffer for indication 172 */ 173 uint16_t att_prepare_handle_value_indication(att_connection_t * att_connection, 174 uint16_t attribute_handle, 175 const uint8_t *value, 176 uint16_t value_len, 177 uint8_t * response_buffer); 178 179 /* 180 * @brief transcation queue of prepared writes, e.g., after disconnect 181 */ 182 void att_clear_transaction_queue(att_connection_t * att_connection); 183 184 // att_read_callback helpers for a various data types 185 186 /* 187 * @brief Handle read of blob like data for att_read_callback 188 * @param blob of data 189 * @param blob_size of blob 190 * @param offset from att_read_callback 191 * @param buffer from att_read_callback 192 * @param buffer_size from att_read_callback 193 * @returns value size for buffer == 0 and num bytes copied otherwise 194 */ 195 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); 196 197 /* 198 * @brief Handle read of little endian unsigned 32 bit value for att_read_callback 199 * @param value 200 * @param offset from att_read_callback 201 * @param buffer from att_read_callback 202 * @param buffer_size from att_read_callback 203 * @returns value size for buffer == 0 and num bytes copied otherwise 204 */ 205 uint16_t att_read_callback_handle_little_endian_32(uint32_t value, uint16_t offset, uint8_t * buffer, uint16_t buffer_size); 206 207 /* 208 * @brief Handle read of little endian unsigned 16 bit value for att_read_callback 209 * @param value 210 * @param offset from att_read_callback 211 * @param buffer from att_read_callback 212 * @param buffer_size from att_read_callback 213 * @returns value size for buffer == 0 and num bytes copied otherwise 214 */ 215 uint16_t att_read_callback_handle_little_endian_16(uint16_t value, uint16_t offset, uint8_t * buffer, uint16_t buffer_size); 216 217 /* 218 * @brief Handle read of single byte for att_read_callback 219 * @param blob of data 220 * @param blob_size of blob 221 * @param offset from att_read_callback 222 * @param buffer from att_read_callback 223 * @param buffer_size from att_read_callback 224 * @returns value size for buffer == 0 and num bytes copied otherwise 225 */ 226 uint16_t att_read_callback_handle_byte(uint8_t value, uint16_t offset, uint8_t * buffer, uint16_t buffer_size); 227 228 229 // experimental client API 230 uint16_t att_uuid_for_handle(uint16_t attribute_handle); 231 232 233 // experimental GATT Server API 234 235 // returns 1 if service found. only primary service. 236 int gatt_server_get_get_handle_range_for_service_with_uuid16(uint16_t uuid16, uint16_t * start_handle, uint16_t * end_handle); 237 238 // returns 0 if not found 239 uint16_t gatt_server_get_value_handle_for_characteristic_with_uuid16(uint16_t start_handle, uint16_t end_handle, uint16_t uuid16); 240 241 // returns 0 if not found 242 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); 243 uint16_t gatt_server_get_client_configuration_handle_for_characteristic_with_uuid16(uint16_t start_handle, uint16_t end_handle, uint16_t characteristic_uuid16); 244 uint16_t gatt_server_get_server_configuration_handle_for_characteristic_with_uuid16(uint16_t start_handle, uint16_t end_handle, uint16_t characteristic_uuid16); 245 246 247 // returns 1 if service found. only primary service. 248 int gatt_server_get_get_handle_range_for_service_with_uuid128(const uint8_t * uuid128, uint16_t * start_handle, uint16_t * end_handle); 249 250 // returns 0 if not found 251 uint16_t gatt_server_get_value_handle_for_characteristic_with_uuid128(uint16_t start_handle, uint16_t end_handle, const uint8_t * uuid128); 252 253 // returns 0 if not found 254 uint16_t gatt_server_get_client_configuration_handle_for_characteristic_with_uuid128(uint16_t start_handle, uint16_t end_handle, const uint8_t * uuid128); 255 256 // non-user functionality for att_server 257 258 /* 259 * @brief Check if writes to handle should be persistent 260 * @param handle 261 * @returns 1 if persistent 262 */ 263 int att_is_persistent_ccc(uint16_t handle); 264 265 266 #if defined __cplusplus 267 } 268 #endif 269 270 #endif // __ATT_H 271