Loading...
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 | /** @file * @brief Bluetooth connection handling */ /* * Copyright (c) 2015-2016 Intel Corporation * * SPDX-License-Identifier: Apache-2.0 */ #ifndef __BT_CONN_H #define __BT_CONN_H /** * @brief Connection management * @defgroup bt_conn Connection management * @ingroup bluetooth * @{ */ #ifdef __cplusplus extern "C" { #endif #include <stdbool.h> #include <bluetooth/bluetooth.h> #include <bluetooth/hci.h> /** Opaque type representing a connection to a remote device */ struct bt_conn; /** Connection parameters for LE connections */ struct bt_le_conn_param { uint16_t interval_min; uint16_t interval_max; uint16_t latency; uint16_t timeout; }; /** Helper to declare connection parameters inline * * @param int_min Minimum Connection Interval (N * 1.25 ms) * @param int_max Maximum Connection Interval (N * 1.25 ms) * @param lat Connection Latency * @param to Supervision Timeout (N * 10 ms) */ #define BT_LE_CONN_PARAM(int_min, int_max, lat, to) \ (&(struct bt_le_conn_param) { \ .interval_min = (int_min), \ .interval_max = (int_max), \ .latency = (lat), \ .timeout = (to), \ }) /** Default LE connection parameters: * Connection Interval: 30-50 ms * Latency: 0 * Timeout: 4 s */ #define BT_LE_CONN_PARAM_DEFAULT BT_LE_CONN_PARAM(BT_GAP_INIT_CONN_INT_MIN, \ BT_GAP_INIT_CONN_INT_MAX, \ 0, 400) /** @brief Increment a connection's reference count. * * Increment the reference count of a connection object. * * @param conn Connection object. * * @return Connection object with incremented reference count. */ struct bt_conn *bt_conn_ref(struct bt_conn *conn); /** @brief Decrement a connection's reference count. * * Decrement the reference count of a connection object. * * @param conn Connection object. */ void bt_conn_unref(struct bt_conn *conn); /** @brief Look up an existing connection by address. * * Look up an existing connection based on the remote address. * * @param peer Remote address. * * @return Connection object or NULL if not found. The caller gets a * new reference to the connection object which must be released with * bt_conn_unref() once done using the object. */ struct bt_conn *bt_conn_lookup_addr_le(const bt_addr_le_t *peer); /** @brief Get destination (peer) address of a connection. * * @param conn Connection object. * * @return Destination address. */ const bt_addr_le_t *bt_conn_get_dst(const struct bt_conn *conn); /** Connection Type */ enum { /** LE Connection Type */ BT_CONN_TYPE_LE, /** BR/EDR Connection Type */ BT_CONN_TYPE_BR, }; /** LE Connection Info Structure */ struct bt_conn_le_info { const bt_addr_le_t *src; /** Source Address */ const bt_addr_le_t *dst; /** Destination Address */ uint16_t interval; /** Connection interval */ uint16_t latency; /** Connection slave latency */ uint16_t timeout; /** Connection supervision timeout */ }; /** BR/EDR Connection Info Structure */ struct bt_conn_br_info { const bt_addr_t *dst; /** Destination BR/EDR address */ }; /** Connection role (master or slave) */ enum { BT_CONN_ROLE_MASTER, BT_CONN_ROLE_SLAVE, }; /** @brief Connection Info Structure * * * @param type Connection Type * @param role Connection Role * @param le LE Connection specific Info * @param br BR/EDR Connection specific Info */ struct bt_conn_info { uint8_t type; uint8_t role; union { struct bt_conn_le_info le; struct bt_conn_br_info br; }; }; /** @brief Get connection info * * @param conn Connection object. * @param info Connection info object. * * @return Zero on success or (negative) error code on failure. */ int bt_conn_get_info(const struct bt_conn *conn, struct bt_conn_info *info); /** @brief Update the connection parameters. * * @param conn Connection object. * @param param Updated connection parameters. * * @return Zero on success or (negative) error code on failure. */ int bt_conn_le_param_update(struct bt_conn *conn, const struct bt_le_conn_param *param); /** @brief Disconnect from a remote device or cancel pending connection. * * Disconnect an active connection with the specified reason code or cancel * pending outgoing connection. * * @param conn Connection to disconnect. * @param reason Reason code for the disconnection. * * @return Zero on success or (negative) error code on failure. */ int bt_conn_disconnect(struct bt_conn *conn, uint8_t reason); /** @brief Initiate an LE connection to a remote device. * * Allows initiate new LE link to remote peer using its address. * Returns a new reference that the the caller is responsible for managing. * * @param peer Remote address. * @param param Initial connection parameters. * * @return Valid connection object on success or NULL otherwise. */ struct bt_conn *bt_conn_create_le(const bt_addr_le_t *peer, const struct bt_le_conn_param *param); /** @brief Automatically connect to remote device if it's in range. * * This function enables/disables automatic connection initiation. * Everytime the device looses the connection with peer, this connection * will be re-established if connectable advertisement from peer is received. * * @param addr Remote Bluetooth address. * @param param If non-NULL, auto connect is enabled with the given * parameters. If NULL, auto connect is disabled. * * @return Zero on success or error code otherwise. */ int bt_le_set_auto_conn(bt_addr_le_t *addr, const struct bt_le_conn_param *param); /** @brief Initiate directed advertising to a remote device * * Allows initiating a new LE connection to remote peer with the remote * acting in central role and the local device in peripheral role. * * The advertising type must be either BT_LE_ADV_DIRECT_IND or * BT_LE_ADV_DIRECT_IND_LOW_DUTY. * * In case of high duty cycle this will result in a callback with * connected() with a new connection or with an error. * * The advertising may be cancelled with bt_conn_disconnect(). * * Returns a new reference that the the caller is responsible for managing. * * @param peer Remote address. * @param param Directed advertising parameters. * * @return Valid connection object on success or NULL otherwise. */ struct bt_conn *bt_conn_create_slave_le(const bt_addr_le_t *peer, const struct bt_le_adv_param *param); /** Security level. */ typedef enum __packed { /** Only for BR/EDR special cases, like SDP */ BT_SECURITY_NONE, /** No encryption and no authentication. */ BT_SECURITY_LOW, /** Encryption and no authentication (no MITM). */ BT_SECURITY_MEDIUM, /** Encryption and authentication (MITM). */ BT_SECURITY_HIGH, /** Authenticated Secure Connections */ BT_SECURITY_FIPS, } bt_security_t; /** @brief Set security level for a connection. * * This function enable security (encryption) for a connection. If device is * already paired with sufficiently strong key encryption will be enabled. If * link is already encrypted with sufficiently strong key this function does * nothing. * * If device is not paired pairing will be initiated. If device is paired and * keys are too weak but input output capabilities allow for strong enough keys * pairing will be initiated. * * This function may return error if required level of security is not possible * to achieve due to local or remote device limitation (eg input output * capabilities). * * @param conn Connection object. * @param sec Requested security level. * * @return 0 on success or negative error */ int bt_conn_security(struct bt_conn *conn, bt_security_t sec); /** @brief Get encryption key size. * * This function gets encryption key size. * If there is no security (encryption) enabled 0 will be returned. * * @param conn Existing connection object. * * @return Encryption key size. */ uint8_t bt_conn_enc_key_size(struct bt_conn *conn); /** @brief Connection callback structure. * * This structure is used for tracking the state of a connection. * It is registered with the help of the bt_conn_cb_register() API. * It's premissible to register multiple instances of this @ref bt_conn_cb * type, in case different modules of an application are interested in * tracking the connection state. If a callback is not of interest for * an instance, it may be set to NULL and will as a consequence not be * used for that instance. */ struct bt_conn_cb { /** @brief A new connection has been established. * * This callback notifies the application of a new connection. * In case the err parameter is non-zero it means that the * connection establishment failed. * * @param conn New connection object. * @param err HCI error. Zero for success, non-zero otherwise. */ void (*connected)(struct bt_conn *conn, uint8_t err); /** @brief A connection has been disconnected. * * This callback notifies the application that a connection * has been disconnected. * * @param conn Connection object. * @param reason HCI reason for the disconnection. */ void (*disconnected)(struct bt_conn *conn, uint8_t reason); /** @brief LE connection parameter update request. * * This callback notifies the application that a remote device * is requesting to update the connection parameters. The * application accepts the parameters by returning true, or * rejects them by returning false. Before accepting, the * application may also adjust the parameters to better suit * its needs. * * It is recommended for an application to have just one of these * callbacks for simplicity. However, if an application registers * multiple it needs to manage the potentially different * requirements for each callback. Each callback gets the * parameters as returned by previous callbacks, i.e. they are not * necessarily the same ones as the remote originally sent. * * @param conn Connection object. * @param param Proposed connection parameters. * * @return true to accept the parameters, or false to reject them. */ bool (*le_param_req)(struct bt_conn *conn, struct bt_le_conn_param *param); /** @brief The parameters for an LE connection have been updated. * * This callback notifies the application that the connection * parameters for an LE connection have been updated. * * @param conn Connection object. * @param interval Connection interval. * @param latency Connection latency. * @param timeout Connection supervision timeout. */ void (*le_param_updated)(struct bt_conn *conn, uint16_t interval, uint16_t latency, uint16_t timeout); #if defined(CONFIG_BLUETOOTH_SMP) /** @brief Remote Identity Address has been resolved. * * This callback notifies the application that a remote * Identity Address has been resolved * * @param conn Connection object. * @param rpa Resolvable Private Address. * @param identity Identity Address. */ void (*identity_resolved)(struct bt_conn *conn, const bt_addr_le_t *rpa, const bt_addr_le_t *identity); #endif /* CONFIG_BLUETOOTH_SMP */ #if defined(CONFIG_BLUETOOTH_SMP) || defined(CONFIG_BLUETOOTH_BREDR) /** @brief The security level of a connection has changed. * * This callback notifies the application that the security level * of a connection has changed. * * @param conn Connection object. * @param level New security level of the connection. */ void (*security_changed)(struct bt_conn *conn, bt_security_t level); #endif /* defined(CONFIG_BLUETOOTH_SMP) || defined(CONFIG_BLUETOOTH_BREDR) */ struct bt_conn_cb *_next; }; /** @brief Register connection callbacks. * * Register callbacks to monitor the state of connections. * * @param cb Callback struct. */ void bt_conn_cb_register(struct bt_conn_cb *cb); /** Authenticated pairing callback structure */ struct bt_conn_auth_cb { void (*passkey_display)(struct bt_conn *conn, unsigned int passkey); void (*passkey_entry)(struct bt_conn *conn); void (*passkey_confirm)(struct bt_conn *conn, unsigned int passkey); void (*cancel)(struct bt_conn *conn); void (*pairing_confirm)(struct bt_conn *conn); #if defined(CONFIG_BLUETOOTH_BREDR) void (*pincode_entry)(struct bt_conn *conn, bool highsec); #endif }; /** @brief Register authentication callbacks. * * Register callbacks to handle authenticated pairing. Passing NULL unregisters * previous callbacks structure. * * @param cb Callback struct. * * @return Zero on success or negative error code otherwise */ int bt_conn_auth_cb_register(const struct bt_conn_auth_cb *cb); /** @brief Reply with entered passkey. * * This function should be called only after passkey_entry callback from * bt_conn_auth_cb structure was called. * * @param conn Connection object. * @param passkey Entered passkey. * * @return Zero on success or negative error code otherwise */ int bt_conn_auth_passkey_entry(struct bt_conn *conn, unsigned int passkey); /** @brief Cancel ongoing authenticated pairing. * * This function allows to cancel ongoing authenticated pairing. * * @param conn Connection object. * * @return Zero on success or negative error code otherwise */ int bt_conn_auth_cancel(struct bt_conn *conn); /** @brief Reply if passkey was confirmed to match by user. * * This function should be called only after passkey_confirm callback from * bt_conn_auth_cb structure was called. * * @param conn Connection object. * * @return Zero on success or negative error code otherwise */ int bt_conn_auth_passkey_confirm(struct bt_conn *conn); /** @brief Reply if incoming pairing was confirmed by user. * * This function should be called only after pairing_confirm callback from * bt_conn_auth_cb structure was called if user confirmed incoming pairing. * * @param conn Connection object. * * @return Zero on success or negative error code otherwise */ int bt_conn_auth_pairing_confirm(struct bt_conn *conn); /** @brief Reply with entered PIN code. * * This function should be called only after PIN code callback from * bt_conn_auth_cb structure was called. It's for legacy 2.0 devices. * * @param conn Connection object. * @param pin Entered PIN code. * * @return Zero on success or negative error code otherwise */ int bt_conn_auth_pincode_entry(struct bt_conn *conn, const char *pin); /** Connection parameters for BR/EDR connections */ struct bt_br_conn_param { bool allow_role_switch; }; /** Helper to declare BR/EDR connection parameters inline * * @param role_switch True if role switch is allowed */ #define BT_BR_CONN_PARAM(role_switch) \ (&(struct bt_br_conn_param) { \ .allow_role_switch = (role_switch), \ }) /** Default BR/EDR connection parameters: * Role switch allowed */ #define BT_BR_CONN_PARAM_DEFAULT BT_BR_CONN_PARAM(true) /** @brief Initiate an BR/EDR connection to a remote device. * * Allows initiate new BR/EDR link to remote peer using its address. * Returns a new reference that the the caller is responsible for managing. * * @param peer Remote address. * @param param Initial connection parameters. * * @return Valid connection object on success or NULL otherwise. */ struct bt_conn *bt_conn_create_br(const bt_addr_t *peer, const struct bt_br_conn_param *param); #ifdef __cplusplus } #endif /** * @} */ #endif /* __BT_CONN_H */ |