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 44 #if defined __cplusplus 45 extern "C" { 46 #endif 47 48 // custom BTstack error codes 49 #define ATT_ERROR_HCI_DISCONNECT_RECEIVED 0x1f 50 51 // custom BTstack ATT error coders 52 #define ATT_ERROR_DATA_MISMATCH 0x7e 53 #define ATT_ERROR_TIMEOUT 0x7F 54 55 typedef struct att_connection { 56 uint16_t con_handle; 57 uint16_t mtu; // initialized to ATT_DEFAULT_MTU (23), negotiated during MTU exchange 58 uint16_t max_mtu; // local maximal L2CAP_MTU, set to l2cap_max_le_mtu() 59 uint8_t encryption_key_size; 60 uint8_t authenticated; 61 uint8_t authorized; 62 } att_connection_t; 63 64 // ATT Client Read Callback for Dynamic Data 65 // - if buffer == NULL, don't copy data, just return size of value 66 // - if buffer != NULL, copy data and return number bytes copied 67 // @param con_handle of hci le connection 68 // @param attribute_handle to be read 69 // @param offset defines start of attribute value 70 // @param buffer 71 // @param buffer_size 72 typedef uint16_t (*att_read_callback_t)(uint16_t con_handle, uint16_t attribute_handle, uint16_t offset, uint8_t * buffer, uint16_t buffer_size); 73 74 // ATT Client Write Callback for Dynamic Data 75 // @param con_handle of hci le connection 76 // @param attribute_handle to be written 77 // @param transaction - ATT_TRANSACTION_MODE_NONE for regular writes, ATT_TRANSACTION_MODE_ACTIVE for prepared writes and ATT_TRANSACTION_MODE_EXECUTE 78 // @param offset into the value - used for queued writes and long attributes 79 // @param buffer 80 // @param buffer_size 81 // @param signature used for signed write commmands 82 // @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 83 typedef int (*att_write_callback_t)(uint16_t con_handle, uint16_t attribute_handle, uint16_t transaction_mode, uint16_t offset, uint8_t *buffer, uint16_t buffer_size); 84 85 // MARK: ATT Operations 86 87 /* 88 * @brief setup ATT database 89 */ 90 void att_set_db(uint8_t const * db); 91 92 /* 93 * @brief set callback for read of dynamic attributes 94 * @param callback 95 */ 96 void att_set_read_callback(att_read_callback_t callback); 97 98 /* 99 * @brief set callback for write of dynamic attributes 100 * @param callback 101 */ 102 void att_set_write_callback(att_write_callback_t callback); 103 104 /* 105 * @brief debug helper, dump ATT database to stdout using log_info 106 */ 107 void att_dump_attributes(void); 108 109 /* 110 * @brief process ATT request against database and put response into response buffer 111 * @param att_connection used for mtu and security properties 112 * @param request_buffer, request_len: ATT request from clinet 113 * @param response_buffer for result 114 * @returns len of data in response buffer. 0 = no response 115 */ 116 uint16_t att_handle_request(att_connection_t * att_connection, 117 uint8_t * request_buffer, 118 uint16_t request_len, 119 uint8_t * response_buffer); 120 121 /* 122 * @brief setup value notification in response buffer for a given handle and value 123 * @param att_connection 124 * @param value, value_len: new attribute value 125 * @param response_buffer for notification 126 */ 127 uint16_t att_prepare_handle_value_notification(att_connection_t * att_connection, 128 uint16_t handle, 129 uint8_t *value, 130 uint16_t value_len, 131 uint8_t * response_buffer); 132 133 /* 134 * @brief setup value indication in response buffer for a given handle and value 135 * @param att_connection 136 * @param value, value_len: new attribute value 137 * @param response_buffer for indication 138 */ 139 uint16_t att_prepare_handle_value_indication(att_connection_t * att_connection, 140 uint16_t handle, 141 uint8_t *value, 142 uint16_t value_len, 143 uint8_t * response_buffer); 144 145 /* 146 * @brief transcation queue of prepared writes, e.g., after disconnect 147 */ 148 void att_clear_transaction_queue(att_connection_t * att_connection); 149 150 // experimental client API 151 uint16_t att_uuid_for_handle(uint16_t handle); 152 153 #if defined __cplusplus 154 } 155 #endif 156 157 #endif // __ATT_H 158