1 /* att_internal.h - Attribute protocol handling */ 2 3 #include <zephyr/bluetooth/l2cap.h> 4 5 /* 6 * Copyright (c) 2015-2016 Intel Corporation 7 * 8 * SPDX-License-Identifier: Apache-2.0 9 */ 10 11 #define BT_EATT_PSM 0x27 12 #define BT_ATT_DEFAULT_LE_MTU 23 13 #define BT_ATT_TIMEOUT_SEC 30 14 #define BT_ATT_TIMEOUT K_SECONDS(BT_ATT_TIMEOUT_SEC) 15 16 /* Local ATT Rx MTU 17 * 18 * This is the local 'Client Rx MTU'/'Server Rx MTU'. Core v5.3 Vol 3 Part F 19 * 3.4.2.2 requires that they are equal. 20 * 21 * The local ATT Server Rx MTU is limited to BT_L2CAP_TX_MTU because the GATT 22 * long attribute read protocol (Core v5.3 Vol 3 Part G 4.8.3) treats the ATT 23 * MTU as a promise about the read size. This requires the server to negotiate 24 * the ATT_MTU down to what it is actually able to send. This will unfortunately 25 * also limit how much the client is allowed to send. 26 */ 27 #define BT_LOCAL_ATT_MTU_EATT MIN(BT_L2CAP_SDU_RX_MTU, BT_L2CAP_SDU_TX_MTU) 28 #define BT_LOCAL_ATT_MTU_UATT MIN(BT_L2CAP_RX_MTU, BT_L2CAP_TX_MTU) 29 30 #define BT_ATT_BUF_SIZE MAX(BT_LOCAL_ATT_MTU_UATT, BT_LOCAL_ATT_MTU_EATT) 31 32 struct bt_att_hdr { 33 uint8_t code; 34 } __packed; 35 36 #define BT_ATT_OP_ERROR_RSP 0x01 37 struct bt_att_error_rsp { 38 uint8_t request; 39 uint16_t handle; 40 uint8_t error; 41 } __packed; 42 43 #define BT_ATT_OP_MTU_REQ 0x02 44 struct bt_att_exchange_mtu_req { 45 uint16_t mtu; 46 } __packed; 47 48 #define BT_ATT_OP_MTU_RSP 0x03 49 struct bt_att_exchange_mtu_rsp { 50 uint16_t mtu; 51 } __packed; 52 53 /* Find Information Request */ 54 #define BT_ATT_OP_FIND_INFO_REQ 0x04 55 struct bt_att_find_info_req { 56 uint16_t start_handle; 57 uint16_t end_handle; 58 } __packed; 59 60 /* Format field values for BT_ATT_OP_FIND_INFO_RSP */ 61 #define BT_ATT_INFO_16 0x01 62 #define BT_ATT_INFO_128 0x02 63 64 struct bt_att_info_16 { 65 uint16_t handle; 66 uint16_t uuid; 67 } __packed; 68 69 struct bt_att_info_128 { 70 uint16_t handle; 71 uint8_t uuid[16]; 72 } __packed; 73 74 /* Find Information Response */ 75 #define BT_ATT_OP_FIND_INFO_RSP 0x05 76 struct bt_att_find_info_rsp { 77 uint8_t format; 78 uint8_t info[0]; 79 } __packed; 80 81 /* Find By Type Value Request */ 82 #define BT_ATT_OP_FIND_TYPE_REQ 0x06 83 struct bt_att_find_type_req { 84 uint16_t start_handle; 85 uint16_t end_handle; 86 uint16_t type; 87 uint8_t value[0]; 88 } __packed; 89 90 struct bt_att_handle_group { 91 uint16_t start_handle; 92 uint16_t end_handle; 93 } __packed; 94 95 /* Find By Type Value Response */ 96 #define BT_ATT_OP_FIND_TYPE_RSP 0x07 97 struct bt_att_find_type_rsp { 98 struct bt_att_handle_group list[0]; 99 } __packed; 100 101 /* Read By Type Request */ 102 #define BT_ATT_OP_READ_TYPE_REQ 0x08 103 struct bt_att_read_type_req { 104 uint16_t start_handle; 105 uint16_t end_handle; 106 uint8_t uuid[0]; 107 } __packed; 108 109 struct bt_att_data { 110 uint16_t handle; 111 uint8_t value[0]; 112 } __packed; 113 114 /* Read By Type Response */ 115 #define BT_ATT_OP_READ_TYPE_RSP 0x09 116 struct bt_att_read_type_rsp { 117 uint8_t len; 118 struct bt_att_data data[0]; 119 } __packed; 120 121 /* Read Request */ 122 #define BT_ATT_OP_READ_REQ 0x0a 123 struct bt_att_read_req { 124 uint16_t handle; 125 } __packed; 126 127 /* Read Response */ 128 #define BT_ATT_OP_READ_RSP 0x0b 129 struct bt_att_read_rsp { 130 uint8_t value[0]; 131 } __packed; 132 133 /* Read Blob Request */ 134 #define BT_ATT_OP_READ_BLOB_REQ 0x0c 135 struct bt_att_read_blob_req { 136 uint16_t handle; 137 uint16_t offset; 138 } __packed; 139 140 /* Read Blob Response */ 141 #define BT_ATT_OP_READ_BLOB_RSP 0x0d 142 struct bt_att_read_blob_rsp { 143 uint8_t value[0]; 144 } __packed; 145 146 /* Read Multiple Request */ 147 #define BT_ATT_READ_MULT_MIN_LEN_REQ 0x04 148 149 #define BT_ATT_OP_READ_MULT_REQ 0x0e 150 struct bt_att_read_mult_req { 151 uint16_t handles[0]; 152 } __packed; 153 154 /* Read Multiple Response */ 155 #define BT_ATT_OP_READ_MULT_RSP 0x0f 156 struct bt_att_read_mult_rsp { 157 uint8_t value[0]; 158 } __packed; 159 160 /* Read by Group Type Request */ 161 #define BT_ATT_OP_READ_GROUP_REQ 0x10 162 struct bt_att_read_group_req { 163 uint16_t start_handle; 164 uint16_t end_handle; 165 uint8_t uuid[0]; 166 } __packed; 167 168 struct bt_att_group_data { 169 uint16_t start_handle; 170 uint16_t end_handle; 171 uint8_t value[0]; 172 } __packed; 173 174 /* Read by Group Type Response */ 175 #define BT_ATT_OP_READ_GROUP_RSP 0x11 176 struct bt_att_read_group_rsp { 177 uint8_t len; 178 struct bt_att_group_data data[0]; 179 } __packed; 180 181 /* Write Request */ 182 #define BT_ATT_OP_WRITE_REQ 0x12 183 struct bt_att_write_req { 184 uint16_t handle; 185 uint8_t value[0]; 186 } __packed; 187 188 /* Write Response */ 189 #define BT_ATT_OP_WRITE_RSP 0x13 190 191 /* Prepare Write Request */ 192 #define BT_ATT_OP_PREPARE_WRITE_REQ 0x16 193 struct bt_att_prepare_write_req { 194 uint16_t handle; 195 uint16_t offset; 196 uint8_t value[0]; 197 } __packed; 198 199 /* Prepare Write Respond */ 200 #define BT_ATT_OP_PREPARE_WRITE_RSP 0x17 201 struct bt_att_prepare_write_rsp { 202 uint16_t handle; 203 uint16_t offset; 204 uint8_t value[0]; 205 } __packed; 206 207 /* Execute Write Request */ 208 #define BT_ATT_FLAG_CANCEL 0x00 209 #define BT_ATT_FLAG_EXEC 0x01 210 211 #define BT_ATT_OP_EXEC_WRITE_REQ 0x18 212 struct bt_att_exec_write_req { 213 uint8_t flags; 214 } __packed; 215 216 /* Execute Write Response */ 217 #define BT_ATT_OP_EXEC_WRITE_RSP 0x19 218 219 /* Handle Value Notification */ 220 #define BT_ATT_OP_NOTIFY 0x1b 221 struct bt_att_notify { 222 uint16_t handle; 223 uint8_t value[0]; 224 } __packed; 225 226 /* Handle Value Indication */ 227 #define BT_ATT_OP_INDICATE 0x1d 228 struct bt_att_indicate { 229 uint16_t handle; 230 uint8_t value[0]; 231 } __packed; 232 233 /* Handle Value Confirm */ 234 #define BT_ATT_OP_CONFIRM 0x1e 235 236 struct bt_att_signature { 237 uint8_t value[12]; 238 } __packed; 239 240 #define BT_ATT_OP_READ_MULT_VL_REQ 0x20 241 struct bt_att_read_mult_vl_req { 242 uint16_t handles[0]; 243 } __packed; 244 245 /* Read Multiple Response */ 246 #define BT_ATT_OP_READ_MULT_VL_RSP 0x21 247 struct bt_att_read_mult_vl_rsp { 248 uint16_t len; 249 uint8_t value[0]; 250 } __packed; 251 252 /* Handle Multiple Value Notification */ 253 #define BT_ATT_OP_NOTIFY_MULT 0x23 254 struct bt_att_notify_mult { 255 uint16_t handle; 256 uint16_t len; 257 uint8_t value[0]; 258 } __packed; 259 260 /* Write Command */ 261 #define BT_ATT_OP_WRITE_CMD 0x52 262 struct bt_att_write_cmd { 263 uint16_t handle; 264 uint8_t value[0]; 265 } __packed; 266 267 /* Signed Write Command */ 268 #define BT_ATT_OP_SIGNED_WRITE_CMD 0xd2 269 struct bt_att_signed_write_cmd { 270 uint16_t handle; 271 uint8_t value[0]; 272 } __packed; 273 274 typedef void (*bt_att_func_t)(struct bt_conn *conn, int err, 275 const void *pdu, uint16_t length, 276 void *user_data); 277 278 typedef int (*bt_att_encode_t)(struct net_buf *buf, size_t len, 279 void *user_data); 280 281 /* ATT request context */ 282 struct bt_att_req { 283 sys_snode_t node; 284 bt_att_func_t func; 285 struct net_buf *buf; 286 #if defined(CONFIG_BT_SMP) 287 bt_att_encode_t encode; 288 uint8_t retrying : 1; 289 uint8_t att_op; 290 size_t len; 291 #endif /* CONFIG_BT_SMP */ 292 void *user_data; 293 }; 294 295 void bt_att_init(void); 296 uint16_t bt_att_get_mtu(struct bt_conn *conn); 297 uint16_t bt_att_get_uatt_mtu(struct bt_conn *conn); 298 struct net_buf *bt_att_create_pdu(struct bt_conn *conn, uint8_t op, 299 size_t len); 300 301 /* Allocate a new request */ 302 struct bt_att_req *bt_att_req_alloc(k_timeout_t timeout); 303 304 /* Free a request */ 305 void bt_att_req_free(struct bt_att_req *req); 306 307 /* Send ATT PDU over a connection */ 308 int bt_att_send(struct bt_conn *conn, struct net_buf *buf); 309 310 /* Send ATT Request over a connection */ 311 int bt_att_req_send(struct bt_conn *conn, struct bt_att_req *req); 312 313 /* Cancel ATT request */ 314 void bt_att_req_cancel(struct bt_conn *conn, struct bt_att_req *req); 315 316 /* Disconnect EATT channels */ 317 int bt_eatt_disconnect(struct bt_conn *conn); 318 319 /** @brief Find a pending ATT request by its user_data pointer. 320 * @param conn The connection the request was issued on. 321 * @param user_data The pointer value to look for. 322 * @return The found request. NULL if not found. 323 */ 324 struct bt_att_req *bt_att_find_req_by_user_data(struct bt_conn *conn, const void *user_data); 325 326 /* Checks if only the fixed ATT channel is connected */ 327 bool bt_att_fixed_chan_only(struct bt_conn *conn); 328 329 /* Clear the out of sync flag on all channels */ 330 void bt_att_clear_out_of_sync_sent(struct bt_conn *conn); 331 332 /* Check if BT_ATT_ERR_DB_OUT_OF_SYNC has been sent on the fixed ATT channel */ 333 bool bt_att_out_of_sync_sent_on_fixed(struct bt_conn *conn); 334 335 typedef void (*bt_gatt_complete_func_t) (struct bt_conn *conn, void *user_data); 336 void bt_att_set_tx_meta_data(struct net_buf *buf, bt_gatt_complete_func_t func, void *user_data, 337 enum bt_att_chan_opt chan_opt); 338 void bt_att_increment_tx_meta_data_attr_count(struct net_buf *buf, uint16_t attr_count); 339 340 bool bt_att_tx_meta_data_match(const struct net_buf *buf, bt_gatt_complete_func_t func, 341 const void *user_data, enum bt_att_chan_opt chan_opt); 342 343 #if defined(CONFIG_BT_EATT) 344 #define BT_ATT_CHAN_OPT(_params) (_params)->chan_opt 345 #else 346 #define BT_ATT_CHAN_OPT(_params) BT_ATT_CHAN_OPT_UNENHANCED_ONLY 347 #endif /* CONFIG_BT_EATT */ 348 349 bool bt_att_chan_opt_valid(struct bt_conn *conn, enum bt_att_chan_opt chan_opt); 350 351 void bt_gatt_req_set_mtu(struct bt_att_req *req, uint16_t mtu); 352
