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 BLUEKITCHEN 24 * GMBH 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 * @title L2CAP 40 * 41 * Logical Link Control and Adaption Protocol 42 * 43 */ 44 45 #ifndef L2CAP_H 46 #define L2CAP_H 47 48 #include "hci.h" 49 #include "l2cap_signaling.h" 50 #include "btstack_util.h" 51 #include "bluetooth.h" 52 53 #if defined __cplusplus 54 extern "C" { 55 #endif 56 57 // check L2CAP MTU 58 #ifdef ENABLE_CLASSIC 59 #if (L2CAP_HEADER_SIZE + L2CAP_MINIMAL_MTU) > HCI_ACL_PAYLOAD_SIZE 60 #error "HCI_ACL_PAYLOAD_SIZE too small for minimal L2CAP MTU of 48 bytes" 61 #endif 62 #endif 63 #ifdef ENABLE_BLE 64 #if (L2CAP_HEADER_SIZE + L2CAP_LE_DEFAULT_MTU) > HCI_ACL_PAYLOAD_SIZE 65 #error "HCI_ACL_PAYLOAD_SIZE too small for minimal L2CAP LE MTU of 23 bytes" 66 #endif 67 #endif 68 69 #define L2CAP_LE_AUTOMATIC_CREDITS 0xffff 70 71 // private structs 72 typedef enum { 73 L2CAP_STATE_CLOSED = 1, // no baseband 74 L2CAP_STATE_WILL_SEND_CREATE_CONNECTION, 75 L2CAP_STATE_WAIT_CONNECTION_COMPLETE, 76 L2CAP_STATE_WAIT_REMOTE_SUPPORTED_FEATURES, 77 L2CAP_STATE_WAIT_INCOMING_SECURITY_LEVEL_UPDATE, 78 L2CAP_STATE_WAIT_OUTGOING_SECURITY_LEVEL_UPDATE, 79 L2CAP_STATE_WAIT_INCOMING_EXTENDED_FEATURES, // only for Enhanced Retransmission Mode 80 L2CAP_STATE_WAIT_OUTGOING_EXTENDED_FEATURES, // only for Enhanced Retransmission Mode 81 L2CAP_STATE_WAIT_CLIENT_ACCEPT_OR_REJECT, 82 L2CAP_STATE_WAIT_CONNECT_RSP, // from peer 83 L2CAP_STATE_CONFIG, 84 L2CAP_STATE_OPEN, 85 L2CAP_STATE_WAIT_DISCONNECT, // from application 86 L2CAP_STATE_WILL_SEND_CONNECTION_REQUEST, 87 L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_INSUFFICIENT_SECURITY, 88 L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_DECLINE, 89 L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_ACCEPT, 90 L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST, 91 L2CAP_STATE_WILL_SEND_DISCONNECT_RESPONSE, 92 L2CAP_STATE_WILL_SEND_LE_CONNECTION_REQUEST, 93 L2CAP_STATE_WILL_SEND_LE_CONNECTION_RESPONSE_DECLINE, 94 L2CAP_STATE_WILL_SEND_LE_CONNECTION_RESPONSE_ACCEPT, 95 L2CAP_STATE_WAIT_LE_CONNECTION_RESPONSE, 96 L2CAP_STATE_EMIT_OPEN_FAILED_AND_DISCARD, 97 L2CAP_STATE_WILL_SEND_ENHANCED_CONNECTION_REQUEST, 98 L2CAP_STATE_WAIT_ENHANCED_CONNECTION_RESPONSE, 99 L2CAP_STATE_WILL_SEND_ENHANCED_CONNECTION_RESPONSE, 100 L2CAP_STATE_WILL_SEND_EHNANCED_RENEGOTIATION_REQUEST, 101 L2CAP_STATE_WAIT_ENHANCED_RENEGOTIATION_RESPONSE, 102 L2CAP_STATE_INVALID, 103 } L2CAP_STATE; 104 105 #define L2CAP_CHANNEL_STATE_VAR_NONE 0 106 #define L2CAP_CHANNEL_STATE_VAR_RCVD_CONF_REQ 1 << 0 107 #define L2CAP_CHANNEL_STATE_VAR_RCVD_CONF_RSP 1 << 1 108 #define L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ 1 << 2 109 #define L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP 1 << 3 110 #define L2CAP_CHANNEL_STATE_VAR_SENT_CONF_REQ 1 << 4 111 #define L2CAP_CHANNEL_STATE_VAR_SENT_CONF_RSP 1 << 5 112 #define L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_MTU 1 << 6 // in CONF RSP, add MTU option 113 #define L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_ERTM 1 << 7 // in CONF RSP, add Retransmission and Flowcontrol option 114 #define L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_CONT 1 << 8 // in CONF RSP, set CONTINUE flag 115 #define L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_INVALID 1 << 9 // in CONF RSP, send UNKNOWN OPTIONS 116 #define L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_REJECTED 1 << 10 // in CONF RSP, send Unacceptable Parameters (ERTM) 117 #define L2CAP_CHANNEL_STATE_VAR_BASIC_FALLBACK_TRIED 1 << 11 // set when ERTM was requested but we want only Basic mode (ERM) 118 #define L2CAP_CHANNEL_STATE_VAR_SEND_CONN_RESP_PEND 1 << 12 // send Connection Respond with pending 119 #define L2CAP_CHANNEL_STATE_VAR_SENT_CONN_RESP_PEND 1 << 13 // send CMD_REJ with reason unknown 120 #define L2CAP_CHANNEL_STATE_VAR_INCOMING 1 << 15 // channel is incoming 121 122 123 typedef enum { 124 L2CAP_CHANNEL_TYPE_CLASSIC, // Classic Basic or ERTM 125 L2CAP_CHANNEL_TYPE_CONNECTIONLESS, // Classic Connectionless 126 L2CAP_CHANNEL_TYPE_CHANNEL_CBM, // LE 127 L2CAP_CHANNEL_TYPE_FIXED_LE, // LE ATT + SM 128 L2CAP_CHANNEL_TYPE_FIXED_CLASSIC, // Classic SM 129 L2CAP_CHANNEL_TYPE_CHANNEL_ECBM // Classic + LE 130 } l2cap_channel_type_t; 131 132 133 /* 134 * @brief L2CAP Segmentation And Reassembly packet type in I-Frames 135 */ 136 typedef enum { 137 L2CAP_SEGMENTATION_AND_REASSEMBLY_UNSEGMENTED_L2CAP_SDU = 0, 138 L2CAP_SEGMENTATION_AND_REASSEMBLY_START_OF_L2CAP_SDU, 139 L2CAP_SEGMENTATION_AND_REASSEMBLY_END_OF_L2CAP_SDU, 140 L2CAP_SEGMENTATION_AND_REASSEMBLY_CONTINUATION_OF_L2CAP_SDU 141 } l2cap_segmentation_and_reassembly_t; 142 143 typedef struct { 144 l2cap_segmentation_and_reassembly_t sar; 145 uint16_t len; 146 uint8_t valid; 147 } l2cap_ertm_rx_packet_state_t; 148 149 typedef struct { 150 l2cap_segmentation_and_reassembly_t sar; 151 uint16_t len; 152 uint8_t tx_seq; 153 uint8_t retry_count; 154 uint8_t retransmission_requested; 155 } l2cap_ertm_tx_packet_state_t; 156 157 typedef struct { 158 // If not mandatory, the use of ERTM can be decided by the remote 159 uint8_t ertm_mandatory; 160 161 // Number of retransmissions that L2CAP is allowed to try before accepting that a packet and the channel is lost. 162 uint8_t max_transmit; 163 164 // time before retransmission of i-frame / Recommended : 2000 ms (ACL Flush timeout not used) 165 uint16_t retransmission_timeout_ms; 166 167 // time after withc s-frames are sent / Recommended: 12000 ms (ACL Flush timeout not used) 168 uint16_t monitor_timeout_ms; 169 170 // MTU for incoming SDUs 171 uint16_t local_mtu; 172 173 // Number of buffers for outgoing data 174 uint8_t num_tx_buffers; 175 176 // Number of packets that can be received out of order (-> our tx_window size) 177 uint8_t num_rx_buffers; 178 179 // Frame Check Sequence (FCS) Option 180 uint8_t fcs_option; 181 182 } l2cap_ertm_config_t; 183 184 // info regarding an actual channel 185 // note: l2cap_fixed_channel and l2cap_channel_t share commmon fields 186 187 typedef struct l2cap_fixed_channel { 188 // linked list - assert: first field 189 btstack_linked_item_t item; 190 191 // channel type 192 l2cap_channel_type_t channel_type; 193 194 // local cid, primary key for channel lookup 195 uint16_t local_cid; 196 197 // packet handler 198 btstack_packet_handler_t packet_handler; 199 200 // send request 201 uint8_t waiting_for_can_send_now; 202 203 // -- end of shared prefix 204 205 } l2cap_fixed_channel_t; 206 207 typedef struct { 208 // linked list - assert: first field 209 btstack_linked_item_t item; 210 211 // channel type 212 l2cap_channel_type_t channel_type; 213 214 // local cid, primary key for channel lookup 215 uint16_t local_cid; 216 217 // packet handler 218 btstack_packet_handler_t packet_handler; 219 220 // send request 221 uint8_t waiting_for_can_send_now; 222 223 // -- end of shared prefix 224 225 // timer 226 btstack_timer_source_t rtx; // also used for ertx 227 228 L2CAP_STATE state; 229 uint16_t state_var; 230 231 // info 232 hci_con_handle_t con_handle; 233 234 bd_addr_t address; 235 bd_addr_type_t address_type; 236 237 uint8_t remote_sig_id; // used by other side, needed for delayed response 238 uint8_t local_sig_id; // own signaling identifier 239 240 uint16_t remote_cid; 241 242 uint16_t local_mtu; 243 uint16_t remote_mtu; 244 245 uint16_t flush_timeout; // default 0xffff 246 247 uint16_t psm; 248 249 gap_security_level_t required_security_level; 250 251 uint16_t reason; // used in decline internal 252 253 uint8_t unknown_option; // used for ConfigResponse 254 255 // Credit-Based Flow-Control mode 256 257 // incoming SDU 258 uint8_t * receive_sdu_buffer; 259 uint16_t receive_sdu_len; 260 uint16_t receive_sdu_pos; 261 262 #ifdef ENABLE_L2CAP_ENHANCED_CREDIT_BASED_FLOW_CONTROL_MODE 263 uint8_t * renegotiate_sdu_buffer; 264 uint16_t renegotiate_mtu; 265 #endif 266 267 // outgoing SDU 268 const uint8_t * send_sdu_buffer; 269 uint16_t send_sdu_len; 270 uint16_t send_sdu_pos; 271 272 // max PDU size 273 uint16_t local_mps; 274 uint16_t remote_mps; 275 276 // credits for outgoing traffic 277 uint16_t credits_outgoing; 278 279 // number of packets remote will be granted 280 uint16_t new_credits_incoming; 281 282 // credits for incoming traffic 283 uint16_t credits_incoming; 284 285 // automatic credits incoming 286 bool automatic_credits; 287 288 #ifdef ENABLE_L2CAP_ENHANCED_CREDIT_BASED_FLOW_CONTROL_MODE 289 uint8_t cid_index; 290 uint8_t num_cids; 291 #endif 292 293 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 294 295 // l2cap channel mode: basic or enhanced retransmission mode 296 l2cap_channel_mode_t mode; 297 298 // retransmission timer 299 btstack_timer_source_t retransmission_timer; 300 301 // monitor timer 302 btstack_timer_source_t monitor_timer; 303 304 // local/remote config options 305 uint16_t local_retransmission_timeout_ms; 306 uint16_t local_monitor_timeout_ms; 307 308 uint16_t remote_retransmission_timeout_ms; 309 uint16_t remote_monitor_timeout_ms; 310 311 uint8_t remote_tx_window_size; 312 313 uint8_t local_max_transmit; 314 uint8_t remote_max_transmit; 315 316 // if ertm is not mandatory, allow fallback to L2CAP Basic Mode - flag 317 uint8_t ertm_mandatory; 318 319 // Frame Chech Sequence (crc16) is present in both directions 320 uint8_t fcs_option; 321 322 // sender: max num of stored outgoing frames 323 uint8_t num_tx_buffers; 324 325 // sender: num stored outgoing frames 326 uint8_t num_stored_tx_frames; 327 328 // sender: number of unacknowledeged I-Frames - frames have been sent, but not acknowledged yet 329 uint8_t unacked_frames; 330 331 // sender: buffer index of oldest packet 332 uint8_t tx_read_index; 333 334 // sender: buffer index to store next tx packet 335 uint8_t tx_write_index; 336 337 // sender: buffer index of packet to send next 338 uint8_t tx_send_index; 339 340 // sender: next seq nr used for sending 341 uint8_t next_tx_seq; 342 343 // sender: selective retransmission requested 344 uint8_t srej_active; 345 346 347 // receiver: max num out-of-order packets // tx_window 348 uint8_t num_rx_buffers; 349 350 // receiver: buffer index of to store packet with delta = 1 351 uint8_t rx_store_index; 352 353 // receiver: value of tx_seq in next expected i-frame 354 uint8_t expected_tx_seq; 355 356 // receiver: request transmission with tx_seq = req_seq and ack up to and including req_seq 357 uint8_t req_seq; 358 359 // receiver: local busy condition 360 uint8_t local_busy; 361 362 // receiver: send RR frame with optional final flag set - flag 363 uint8_t send_supervisor_frame_receiver_ready; 364 365 // receiver: send RR frame with poll bit set 366 uint8_t send_supervisor_frame_receiver_ready_poll; 367 368 // receiver: send RNR frame - flag 369 uint8_t send_supervisor_frame_receiver_not_ready; 370 371 // receiver: send REJ frame - flag 372 uint8_t send_supervisor_frame_reject; 373 374 // receiver: send SREJ frame - flag 375 uint8_t send_supervisor_frame_selective_reject; 376 377 // set final bit after poll packet with poll bit was received 378 uint8_t set_final_bit_after_packet_with_poll_bit_set; 379 380 // receiver: meta data for out-of-order frames 381 l2cap_ertm_rx_packet_state_t * rx_packets_state; 382 383 // sender: retransmission state 384 l2cap_ertm_tx_packet_state_t * tx_packets_state; 385 386 // receiver: reassemly pos 387 uint16_t reassembly_pos; 388 389 // receiver: reassemly sdu length 390 uint16_t reassembly_sdu_length; 391 392 // receiver: eassembly buffer 393 uint8_t * reassembly_buffer; 394 395 // receiver: num_rx_buffers of size local_mps 396 uint8_t * rx_packets_data; 397 398 // sender: num_tx_buffers of size local_mps 399 uint8_t * tx_packets_data; 400 401 #endif 402 } l2cap_channel_t; 403 404 // info regarding potential connections 405 typedef struct { 406 // linked list - assert: first field 407 btstack_linked_item_t item; 408 409 // service id 410 uint16_t psm; 411 412 // max local mtu for basic mode, min remote mtu for enhanced credit-based flow-control mode 413 uint16_t mtu; 414 415 // internal connection 416 btstack_packet_handler_t packet_handler; 417 418 // required security level 419 gap_security_level_t required_security_level; 420 421 // requires authorization 422 bool requires_authorization; 423 424 } l2cap_service_t; 425 426 427 typedef struct l2cap_signaling_response { 428 hci_con_handle_t handle; 429 uint8_t sig_id; 430 uint8_t code; 431 uint16_t cid; // source cid for CONNECTION REQUEST 432 uint16_t data; // infoType for INFORMATION REQUEST, result for CONNECTION REQUEST and COMMAND UNKNOWN 433 } l2cap_signaling_response_t; 434 435 436 void l2cap_register_fixed_channel(btstack_packet_handler_t packet_handler, uint16_t channel_id); 437 bool l2cap_can_send_fixed_channel_packet_now(hci_con_handle_t con_handle, uint16_t channel_id); 438 void l2cap_request_can_send_fix_channel_now_event(hci_con_handle_t con_handle, uint16_t channel_id); 439 uint8_t l2cap_send_connectionless(hci_con_handle_t con_handle, uint16_t cid, uint8_t *data, uint16_t len); 440 uint8_t l2cap_send_prepared_connectionless(hci_con_handle_t con_handle, uint16_t cid, uint16_t len); 441 442 // PTS Testing 443 int l2cap_send_echo_request(hci_con_handle_t con_handle, uint8_t *data, uint16_t len); 444 void l2cap_require_security_level_2_for_outgoing_sdp(void); 445 446 // Used by RFCOMM - similar to l2cap_can-send_packet_now but does not check if outgoing buffer is reserved 447 bool l2cap_can_send_prepared_packet_now(uint16_t local_cid); 448 449 /* API_START */ 450 451 // 452 // PSM numbers from https://www.bluetooth.com/specifications/assigned-numbers/logical-link-control 453 // 454 #define PSM_SDP BLUETOOTH_PROTOCOL_SDP 455 #define PSM_RFCOMM BLUETOOTH_PROTOCOL_RFCOMM 456 #define PSM_BNEP BLUETOOTH_PROTOCOL_BNEP 457 // @TODO: scrape PSMs Bluetooth SIG site and put in bluetooth_psm.h or bluetooth_l2cap.h 458 #define PSM_HID_CONTROL 0x11 459 #define PSM_HID_INTERRUPT 0x13 460 #define PSM_ATT 0x1f 461 #define PSM_IPSP 0x23 462 463 /** 464 * @brief Set up L2CAP and register L2CAP with HCI layer. 465 */ 466 void l2cap_init(void); 467 468 /** 469 * @brief Add event packet handler for LE Connection Parameter Update events 470 */ 471 void l2cap_add_event_handler(btstack_packet_callback_registration_t * callback_handler); 472 473 /** 474 * @brief Remove event packet handler. 475 */ 476 void l2cap_remove_event_handler(btstack_packet_callback_registration_t * callback_handler); 477 478 /** 479 * @brief Get max MTU for Classic connections based on btstack configuration 480 */ 481 uint16_t l2cap_max_mtu(void); 482 483 /** 484 * @brief Get max MTU for LE connections based on btstack configuration 485 */ 486 uint16_t l2cap_max_le_mtu(void); 487 488 /** 489 * @brief Set the max MTU for LE connections, if not set l2cap_max_mtu() will be used. 490 */ 491 void l2cap_set_max_le_mtu(uint16_t max_mtu); 492 493 /** 494 * @brief Creates L2CAP channel to the PSM of a remote device with baseband address. A new baseband connection will be initiated if necessary. 495 * @param packet_handler 496 * @param address 497 * @param psm 498 * @param mtu 499 * @param local_cid 500 * @return status 501 */ 502 uint8_t l2cap_create_channel(btstack_packet_handler_t packet_handler, bd_addr_t address, uint16_t psm, uint16_t mtu, uint16_t * out_local_cid); 503 504 /** 505 * @brief Disconnects L2CAP channel with given identifier. 506 * @param local_cid 507 * @return status ERROR_CODE_SUCCESS if successful or L2CAP_LOCAL_CID_DOES_NOT_EXIST 508 */ 509 uint8_t l2cap_disconnect(uint16_t local_cid); 510 511 /** 512 * @brief Queries the maximal transfer unit (MTU) for L2CAP channel with given identifier. 513 */ 514 uint16_t l2cap_get_remote_mtu_for_local_cid(uint16_t local_cid); 515 516 /** 517 * @brief Sends L2CAP data packet to the channel with given identifier. 518 * @note For channel in credit-based flow control mode, data needs to stay valid until .. event 519 * @param local_cid 520 * @param data to send 521 * @param len of data 522 * @return status 523 */ 524 uint8_t l2cap_send(uint16_t local_cid, const uint8_t *data, uint16_t len); 525 526 /** 527 * @brief Registers L2CAP service with given PSM and MTU, and assigns a packet handler. 528 * @param packet_handler 529 * @param psm 530 * @param mtu 531 * @param security_level 532 * @return status ERROR_CODE_SUCCESS if successful, otherwise L2CAP_SERVICE_ALREADY_REGISTERED or BTSTACK_MEMORY_ALLOC_FAILED 533 */ 534 uint8_t l2cap_register_service(btstack_packet_handler_t packet_handler, uint16_t psm, uint16_t mtu, gap_security_level_t security_level); 535 536 /** 537 * @brief Unregisters L2CAP service with given PSM. 538 */ 539 uint8_t l2cap_unregister_service(uint16_t psm); 540 541 /** 542 * @brief Accepts incoming L2CAP connection. 543 */ 544 void l2cap_accept_connection(uint16_t local_cid); 545 546 /** 547 * @brief Deny incoming L2CAP connection. 548 */ 549 void l2cap_decline_connection(uint16_t local_cid); 550 551 /** 552 * @brief Check if outgoing buffer is available and that there's space on the Bluetooth module 553 * @return true if packet can be sent 554 */ 555 bool l2cap_can_send_packet_now(uint16_t local_cid); 556 557 /** 558 * @brief Request emission of L2CAP_EVENT_CAN_SEND_NOW as soon as possible 559 * @note L2CAP_EVENT_CAN_SEND_NOW might be emitted during call to this function 560 * so packet handler should be ready to handle it 561 * @param local_cid 562 * @return status 563 */ 564 uint8_t l2cap_request_can_send_now_event(uint16_t local_cid); 565 566 /** 567 * @brief Reserve outgoing buffer 568 * @note Only for L2CAP Basic Mode Channels 569 * @note Must only be called after a 'can send now' check or event 570 * @note Asserts if packet buffer is already reserved 571 */ 572 void l2cap_reserve_packet_buffer(void); 573 574 /** 575 * @brief Get outgoing buffer and prepare data. 576 * @note Only for L2CAP Basic Mode Channels 577 */ 578 uint8_t *l2cap_get_outgoing_buffer(void); 579 580 /** 581 * @brief Send L2CAP packet prepared in outgoing buffer to channel 582 * @note Only for L2CAP Basic Mode Channels 583 */ 584 uint8_t l2cap_send_prepared(uint16_t local_cid, uint16_t len); 585 586 /** 587 * @brief Release outgoing buffer (only needed if l2cap_send_prepared is not called) 588 * @note Only for L2CAP Basic Mode Channels 589 */ 590 void l2cap_release_packet_buffer(void); 591 592 // 593 // Connection-Oriented Channels in Enhanced Retransmission Mode - ERTM 594 // 595 596 /** 597 * @brief Creates L2CAP channel to the PSM of a remote device with baseband address using Enhanced Retransmission Mode. 598 * A new baseband connection will be initiated if necessary. 599 * @param packet_handler 600 * @param address 601 * @param psm 602 * @param ertm_config 603 * @param buffer to store reassembled rx packet, out-of-order packets and unacknowledged outgoing packets with their tretransmission timers 604 * @param size of buffer 605 * @param local_cid 606 * @return status 607 */ 608 uint8_t l2cap_ertm_create_channel(btstack_packet_handler_t packet_handler, bd_addr_t address, uint16_t psm, 609 l2cap_ertm_config_t * ertm_contig, uint8_t * buffer, uint32_t size, uint16_t * out_local_cid); 610 611 /** 612 * @brief Accepts incoming L2CAP connection for Enhanced Retransmission Mode 613 * @param local_cid 614 * @param ertm_config 615 * @param buffer to store reassembled rx packet, out-of-order packets and unacknowledged outgoing packets with their tretransmission timers 616 * @param size of buffer 617 * @return status 618 */ 619 uint8_t l2cap_ertm_accept_connection(uint16_t local_cid, l2cap_ertm_config_t * ertm_contig, uint8_t * buffer, uint32_t size); 620 621 /** 622 * @brief Deny incoming incoming L2CAP connection for Enhanced Retransmission Mode 623 * @param local_cid 624 * @return status 625 */ 626 uint8_t l2cap_ertm_decline_connection(uint16_t local_cid); 627 628 /** 629 * @brief ERTM Set channel as busy. 630 * @note Can be cleared by l2cap_ertm_set_ready 631 * @param local_cid 632 * @return status 633 */ 634 uint8_t l2cap_ertm_set_busy(uint16_t local_cid); 635 636 /** 637 * @brief ERTM Set channel as ready 638 * @note Used after l2cap_ertm_set_busy 639 * @param local_cid 640 * @return status 641 */ 642 uint8_t l2cap_ertm_set_ready(uint16_t local_cid); 643 644 645 // 646 // L2CAP Connection-Oriented Channels in LE Credit-Based Flow-Control Mode - CBM 647 // 648 649 /** 650 * @brief Register L2CAP service in LE Credit-Based Flow-Control Mode 651 * @note MTU and initial credits are specified in l2cap_cbm_accept_connection(..) call 652 * @param packet_handler 653 * @param psm 654 * @param security_level 655 */ 656 uint8_t l2cap_cbm_register_service(btstack_packet_handler_t packet_handler, uint16_t psm, gap_security_level_t security_level); 657 658 /** 659 * @brief Unregister L2CAP service in LE Credit-Based Flow-Control Mode 660 * @param psm 661 */ 662 663 uint8_t l2cap_cbm_unregister_service(uint16_t psm); 664 665 /* 666 * @brief Accept incoming connection LE Credit-Based Flow-Control Mode 667 * @param local_cid L2CAP Channel Identifier 668 * @param receive_buffer buffer used for reassembly of L2CAP LE Information Frames into service data unit (SDU) with given MTU 669 * @param receive_buffer_size buffer size equals MTU 670 * @param initial_credits Number of initial credits provided to peer or L2CAP_LE_AUTOMATIC_CREDITS to enable automatic credits 671 */ 672 673 uint8_t l2cap_cbm_accept_connection(uint16_t local_cid, uint8_t * receive_sdu_buffer, uint16_t mtu, uint16_t initial_credits); 674 675 /** 676 * @brief Deecline connection in LE Credit-Based Flow-Control Mode 677 * @param local_cid L2CAP Channel Identifier 678 * @param result result, see L2CAP_CBM_CONNECTION_RESULT_SUCCESS in bluetooth.h 679 */ 680 681 uint8_t l2cap_cbm_decline_connection(uint16_t local_cid, uint16_t result); 682 683 /** 684 * @brief Create outgoing channel in LE Credit-Based Flow-Control Mode 685 * @param packet_handler Packet handler for this connection 686 * @param con_handle HCI Connection Handle, LE transport 687 * @param psm Service PSM to connect to 688 * @param receive_buffer buffer used for reassembly of L2CAP LE Information Frames into service data unit (SDU) with given MTU 689 * @param receive_buffer_size buffer size equals MTU 690 * @param initial_credits Number of initial credits provided to peer or L2CAP_LE_AUTOMATIC_CREDITS to enable automatic credits 691 * @param security_level Minimum required security level 692 * @param out_local_cid L2CAP LE Channel Identifier is stored here 693 */ 694 uint8_t l2cap_cbm_create_channel(btstack_packet_handler_t packet_handler, hci_con_handle_t con_handle, 695 uint16_t psm, uint8_t * receive_sdu_buffer, uint16_t mtu, uint16_t initial_credits, gap_security_level_t security_level, 696 uint16_t * out_local_cid); 697 698 /** 699 * @brief Provide credits for channel in LE Credit-Based Flow-Control Mode 700 * @param local_cid L2CAP Channel Identifier 701 * @param credits Number additional credits for peer 702 */ 703 uint8_t l2cap_cbm_provide_credits(uint16_t local_cid, uint16_t credits); 704 705 // 706 // L2CAP Connection-Oriented Channels in Enhanced Credit-Based Flow-Control Mode - ECBM 707 // 708 709 /** 710 * @brief Register L2CAP service in Enhanced Credit-Based Flow-Control Mode 711 * @note MTU and initial credits are specified in l2cap_enhanced_accept_connection(..) call 712 * @param packet_handler 713 * @param psm 714 * @param min_remote_mtu 715 * @param security_level 716 * @oaram authorization_required 717 * @return status 718 */ 719 uint8_t l2cap_ecbm_register_service(btstack_packet_handler_t packet_handler, uint16_t psm, uint16_t min_remote_mtu, 720 gap_security_level_t security_level, bool authorization_required); 721 722 /** 723 * @brief Unregister L2CAP service in Enhanced Credit-Based Flow-Control Mode 724 * @param psm 725 * @return status 726 */ 727 728 uint8_t l2cap_ecbm_unregister_service(uint16_t psm); 729 730 /** 731 * @brief Set Minimal MPS for channel in Enhanced Credit-Based Flow-Control Mode 732 * @param mps_min 733 */ 734 void l2cap_ecbm_mps_set_min(uint16_t mps_min); 735 736 /** 737 * @brief Set Minimal MPS for channel in Enhanced Credit-Based Flow-Control Mode 738 * @param mps_max 739 */ 740 void l2cap_ecbm_mps_set_max(uint16_t mps_max); 741 742 /** 743 * @brief Create outgoing channel in Enhanced Credit-Based Flow-Control Mode 744 * @note receive_buffer points to an array of receive buffers with num_channels elements 745 * @note out_local_cid points to an array where CID is stored with num_channel elements 746 * @param packet_handler Packet handler for this connection 747 * @param con_handle HCI Connection Handle 748 * @param security_level Minimum required security level 749 * @param psm Service PSM to connect to 750 * @param num_channels number of channels to create 751 * @param initial_credits Number of initial credits provided to peer per channel or L2CAP_LE_AUTOMATIC_CREDITS to enable automatic credits 752 * @param receive_buffer_size buffer size equals MTU 753 * @param receive_buffers Array of buffers used for reassembly of L2CAP Information Frames into service data unit (SDU) with given MTU 754 * @param out_local_cids Array of L2CAP Channel Identifiers is stored here on success 755 * @return status 756 */ 757 uint8_t l2cap_ecbm_create_channels(btstack_packet_handler_t packet_handler, hci_con_handle_t con_handle, 758 gap_security_level_t security_level, 759 uint16_t psm, uint8_t num_channels, uint16_t initial_credits, uint16_t receive_buffer_size, 760 uint8_t ** receive_buffers, uint16_t * out_local_cids); 761 762 /** 763 * @brief Accept incoming connection Enhanced Credit-Based Flow-Control Mode 764 * @param local_cid from L2CAP_EVENT_INCOMING_DATA_CONNECTION 765 * @param num_channels 766 * @param initial_credits Number of initial credits provided to peer per channel or L2CAP_LE_AUTOMATIC_CREDITS to enable automatic credits 767 * @param receive_buffer_size 768 * @param receive_buffers Array of buffers used for reassembly of L2CAP Information Frames into service data unit (SDU) with given MTU 769 * @param out_local_cids Array of L2CAP Channel Identifiers is stored here on success 770 * @return status 771 */ 772 uint8_t l2cap_ecbm_accept_channels(uint16_t local_cid, uint8_t num_channels, uint16_t initial_credits, 773 uint16_t receive_buffer_size, uint8_t ** receive_buffers, uint16_t * out_local_cids); 774 /** 775 * @brief Decline connection in Enhanced Credit-Based Flow-Control Mode 776 * @param local_cid from L2CAP_EVENT_INCOMING_DATA_CONNECTION 777 * @param result See L2CAP_ECBM_CONNECTION_RESULT_ALL_SUCCESS in bluetooth.h 778 * @return status 779 */ 780 uint8_t l2cap_ecbm_decline_channels(uint16_t local_cid, uint16_t result); 781 782 /** 783 * @brief Provide credits for channel in Enhanced Credit-Based Flow-Control Mode 784 * @param local_cid L2CAP Channel Identifier 785 * @param credits Number additional credits for peer 786 * @return status 787 */ 788 uint8_t l2cap_ecbm_provide_credits(uint16_t local_cid, uint16_t credits); 789 790 /** 791 * @brief Request emission of L2CAP_EVENT_ECBM_CAN_SEND_NOW as soon as possible 792 * @note L2CAP_EVENT_ECBM_CAN_SEND_NOW might be emitted during call to this function 793 * so packet handler should be ready to handle it 794 * @param local_cid L2CAP Channel Identifier 795 * @return status 796 */ 797 uint8_t l2cap_ecbm_request_can_send_now_event(uint16_t local_cid); 798 799 /** 800 * @brief Reconfigure MPS/MTU of local channels 801 * @param num_cids 802 * @param local_cids array of local_cids to reconfigure 803 * @param receive_buffer_size buffer size equals MTU 804 * @param receive_buffers Array of buffers used for reassembly of L2CAP Information Frames into service data unit (SDU) with given MTU 805 * @return status 806 */ 807 uint8_t l2cap_ecbm_reconfigure_channels(uint8_t num_cids, uint16_t * local_cids, int16_t receive_buffer_size, uint8_t ** receive_buffers); 808 809 /** 810 * @brief Trigger pending connection responses after pairing completed 811 * @note Must be called after receiving an SM_PAIRING_COMPLETE event, will be removed eventually 812 * @param con_handle 813 */ 814 void l2cap_ecbm_trigger_pending_connection_responses(hci_con_handle_t con_handle); 815 816 /** 817 * @brief De-Init L2CAP 818 */ 819 void l2cap_deinit(void); 820 821 /* API_END */ 822 823 824 // @deprecated - please use l2cap_ertm_create_channel 825 uint8_t l2cap_create_ertm_channel(btstack_packet_handler_t packet_handler, bd_addr_t address, uint16_t psm, l2cap_ertm_config_t * ertm_contig, uint8_t * buffer, uint32_t size, uint16_t * out_local_cid); 826 827 // @deprecated - please use l2cap_ertm_accept_connection 828 uint8_t l2cap_accept_ertm_connection(uint16_t local_cid, l2cap_ertm_config_t * ertm_contig, uint8_t * buffer, uint32_t size); 829 830 // @deprecated - please use l2cap_cbm_register_service 831 uint8_t l2cap_le_register_service(btstack_packet_handler_t packet_handler, uint16_t psm, gap_security_level_t security_level); 832 833 // @deprecated - please use l2cap_cbm_unregister_service 834 uint8_t l2cap_le_unregister_service(uint16_t psm); 835 836 // @deprecated - please use l2cap_cbm_accept_connection 837 uint8_t l2cap_le_accept_connection(uint16_t local_cid, uint8_t * receive_sdu_buffer, uint16_t mtu, uint16_t initial_credits); 838 839 // @deprecated - please use l2cap_cbm_decline_connection 840 uint8_t l2cap_le_decline_connection(uint16_t local_cid); 841 842 // @deprecated - please use l2cap_cbm_create_channel 843 uint8_t l2cap_le_create_channel(btstack_packet_handler_t packet_handler, hci_con_handle_t con_handle, 844 uint16_t psm, uint8_t * receive_sdu_buffer, uint16_t mtu, uint16_t initial_credits, gap_security_level_t security_level, 845 uint16_t * out_local_cid); 846 847 // @deprecated - please use l2cap_cbm_provide_credits 848 uint8_t l2cap_le_provide_credits(uint16_t local_cid, uint16_t credits); 849 850 // @deprecated - please use l2cap_can_send_now 851 bool l2cap_le_can_send_now(uint16_t local_cid); 852 853 // @deprecated - please use l2cap_request_can_send_now_event 854 uint8_t l2cap_le_request_can_send_now_event(uint16_t local_cid); 855 856 // @deprecated - please use l2cap_send 857 uint8_t l2cap_le_send_data(uint16_t local_cid, const uint8_t * data, uint16_t size); 858 859 // @deprecated - please use l2cap_disconnect 860 uint8_t l2cap_le_disconnect(uint16_t local_cid); 861 862 863 #if defined __cplusplus 864 } 865 #endif 866 867 #endif // L2CAP_H 868