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 #define BTSTACK_FILE__ "l2cap.c" 39 40 /* 41 * l2cap.c 42 * Logical Link Control and Adaption Protocol (L2CAP) 43 */ 44 45 #include "l2cap.h" 46 #include "hci.h" 47 #include "hci_dump.h" 48 #include "bluetooth_sdp.h" 49 #include "bluetooth_psm.h" 50 #include "btstack_bool.h" 51 #include "btstack_debug.h" 52 #include "btstack_event.h" 53 #include "btstack_memory.h" 54 55 #ifdef ENABLE_L2CAP_LE_CREDIT_BASED_FLOW_CONTROL_MODE 56 // TODO avoid dependency on higher layer: used to trigger pairing for outgoing connections 57 #include "ble/sm.h" 58 #endif 59 60 #include <stdarg.h> 61 #include <string.h> 62 63 /* 64 * @brief L2CAP Supervisory function in S-Frames 65 */ 66 typedef enum { 67 L2CAP_SUPERVISORY_FUNCTION_RR_RECEIVER_READY = 0, 68 L2CAP_SUPERVISORY_FUNCTION_REJ_REJECT, 69 L2CAP_SUPERVISORY_FUNCTION_RNR_RECEIVER_NOT_READY, 70 L2CAP_SUPERVISORY_FUNCTION_SREJ_SELECTIVE_REJECT 71 } l2cap_supervisory_function_t; 72 73 /** 74 * @brief L2CAP Information Types used in Information Request & Response 75 */ 76 typedef enum { 77 L2CAP_INFO_TYPE_CONNECTIONLESS_MTU = 1, 78 L2CAP_INFO_TYPE_EXTENDED_FEATURES_SUPPORTED, 79 L2CAP_INFO_TYPE_FIXED_CHANNELS_SUPPORTED, 80 } l2cap_info_type_t; 81 82 /** 83 * @brief L2CAP Configuration Option Types used in Configurateion Request & Response 84 */ 85 typedef enum { 86 L2CAP_CONFIG_OPTION_TYPE_MAX_TRANSMISSION_UNIT = 1, 87 L2CAP_CONFIG_OPTION_TYPE_FLUSH_TIMEOUT, 88 L2CAP_CONFIG_OPTION_TYPE_QUALITY_OF_SERVICE, 89 L2CAP_CONFIG_OPTION_TYPE_RETRANSMISSION_AND_FLOW_CONTROL, 90 L2CAP_CONFIG_OPTION_TYPE_FRAME_CHECK_SEQUENCE, 91 L2CAP_CONFIG_OPTION_TYPE_EXTENDED_FLOW_SPECIFICATION, 92 L2CAP_CONFIG_OPTION_TYPE_EXTENDED_WINDOW_SIZE, 93 } l2cap_config_option_type_t; 94 95 96 #define L2CAP_SIG_ID_INVALID 0 97 98 // size of HCI ACL + L2CAP Header for regular data packets (8) 99 #define COMPLETE_L2CAP_HEADER (HCI_ACL_HEADER_SIZE + L2CAP_HEADER_SIZE) 100 101 // L2CAP Configuration Result Codes 102 #define L2CAP_CONF_RESULT_SUCCESS 0x0000 103 #define L2CAP_CONF_RESULT_UNACCEPTABLE_PARAMETERS 0x0001 104 #define L2CAP_CONF_RESULT_REJECT 0x0002 105 #define L2CAP_CONF_RESULT_UNKNOWN_OPTIONS 0x0003 106 #define L2CAP_CONF_RESULT_PENDING 0x0004 107 #define L2CAP_CONF_RESULT_FLOW_SPEC_REJECTED 0x0005 108 109 // L2CAP Reject Result Codes 110 #define L2CAP_REJ_CMD_UNKNOWN 0x0000 111 112 // Response Timeout eXpired 113 #define L2CAP_RTX_TIMEOUT_MS 10000 114 115 // Extended Response Timeout eXpired 116 #define L2CAP_ERTX_TIMEOUT_MS 120000 117 118 // nr of buffered acl packets in outgoing queue to get max performance 119 #define NR_BUFFERED_ACL_PACKETS 3 120 121 // used to cache l2cap rejects, echo, and informational requests 122 #define NR_PENDING_SIGNALING_RESPONSES 3 123 124 // nr of credits provided to remote if credits fall below watermark 125 #define L2CAP_CREDIT_BASED_FLOW_CONTROL_MODE_AUTOMATIC_CREDITS_WATERMARK 5 126 #define L2CAP_CREDIT_BASED_FLOW_CONTROL_MODE_AUTOMATIC_CREDITS_INCREMENT 5 127 128 // offsets for L2CAP SIGNALING COMMANDS 129 #define L2CAP_SIGNALING_COMMAND_CODE_OFFSET 0 130 #define L2CAP_SIGNALING_COMMAND_SIGID_OFFSET 1 131 #define L2CAP_SIGNALING_COMMAND_LENGTH_OFFSET 2 132 #define L2CAP_SIGNALING_COMMAND_DATA_OFFSET 4 133 134 #ifdef ENABLE_LE_DATA_CHANNELS 135 #warning "ENABLE_LE_DATA_CHANNELS has been deprecated." 136 #warning "Please use ENABLE_L2CAP_LE_CREDIT_BASED_FLOW_CONTROL_MODE instead in btstack_config.h" 137 #define ENABLE_L2CAP_LE_CREDIT_BASED_FLOW_CONTROL_MODE 138 #endif 139 140 #if defined(ENABLE_L2CAP_LE_CREDIT_BASED_FLOW_CONTROL_MODE) || defined(ENABLE_L2CAP_ENHANCED_CREDIT_BASED_FLOW_CONTROL_MODE) 141 #define L2CAP_USES_CREDIT_BASED_CHANNELS 142 #endif 143 144 #if defined(L2CAP_USES_CREDIT_BASED_CHANNELS) || defined(ENABLE_CLASSIC) 145 #define L2CAP_USES_CHANNELS 146 #endif 147 148 // prototypes 149 static void l2cap_run(void); 150 static void l2cap_hci_event_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size); 151 static void l2cap_acl_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size ); 152 static void l2cap_notify_channel_can_send(void); 153 static void l2cap_emit_can_send_now(btstack_packet_handler_t packet_handler, uint16_t channel); 154 static uint8_t l2cap_next_sig_id(void); 155 static l2cap_fixed_channel_t * l2cap_fixed_channel_for_channel_id(uint16_t local_cid); 156 #ifdef ENABLE_CLASSIC 157 static void l2cap_handle_security_level_incoming_sufficient(l2cap_channel_t * channel); 158 static int l2cap_security_level_0_allowed_for_PSM(uint16_t psm); 159 static void l2cap_handle_remote_supported_features_received(l2cap_channel_t * channel); 160 static void l2cap_handle_connection_complete(hci_con_handle_t con_handle, l2cap_channel_t * channel); 161 static void l2cap_handle_information_request_complete(hci_connection_t * connection); 162 static inline l2cap_service_t * l2cap_get_service(uint16_t psm); 163 static void l2cap_emit_channel_opened(l2cap_channel_t *channel, uint8_t status); 164 static void l2cap_emit_channel_closed(l2cap_channel_t *channel); 165 static void l2cap_emit_incoming_connection(l2cap_channel_t *channel); 166 static int l2cap_channel_ready_for_open(l2cap_channel_t *channel); 167 #endif 168 #ifdef ENABLE_L2CAP_LE_CREDIT_BASED_FLOW_CONTROL_MODE 169 static void l2cap_cbm_emit_channel_opened(l2cap_channel_t *channel, uint8_t status); 170 static void l2cap_cbm_emit_channel_closed(l2cap_channel_t * channel); 171 static void l2cap_cbm_emit_incoming_connection(l2cap_channel_t *channel); 172 static void l2cap_cbm_notify_channel_can_send(l2cap_channel_t *channel); 173 static void l2cap_cbm_finialize_channel_close(l2cap_channel_t *channel); 174 static inline l2cap_service_t * l2cap_cbm_get_service(uint16_t le_psm); 175 #endif 176 #ifdef L2CAP_USES_CREDIT_BASED_CHANNELS 177 static void l2cap_credit_based_send_pdu(l2cap_channel_t *channel); 178 static void l2cap_credit_based_send_credits(l2cap_channel_t *channel); 179 static bool l2cap_credit_based_handle_credit_indication(hci_con_handle_t handle, const uint8_t * command, uint16_t len); 180 static void l2cap_credit_based_handle_pdu(l2cap_channel_t * l2cap_channel, const uint8_t * packet, uint16_t size); 181 #endif 182 #ifdef L2CAP_USES_CHANNELS 183 static uint16_t l2cap_next_local_cid(void); 184 static l2cap_channel_t * l2cap_get_channel_for_local_cid(uint16_t local_cid); 185 static void l2cap_emit_simple_event_with_cid(l2cap_channel_t * channel, uint8_t event_code); 186 static void l2cap_dispatch_to_channel(l2cap_channel_t *channel, uint8_t type, uint8_t * data, uint16_t size); 187 static l2cap_channel_t * l2cap_create_channel_entry(btstack_packet_handler_t packet_handler, l2cap_channel_type_t channel_type, bd_addr_t address, bd_addr_type_t address_type, 188 uint16_t psm, uint16_t local_mtu, gap_security_level_t security_level); 189 static void l2cap_finalize_channel_close(l2cap_channel_t *channel); 190 static void l2cap_free_channel_entry(l2cap_channel_t * channel); 191 #endif 192 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 193 static void l2cap_ertm_notify_channel_can_send(l2cap_channel_t * channel); 194 static void l2cap_ertm_monitor_timeout_callback(btstack_timer_source_t * ts); 195 static void l2cap_ertm_retransmission_timeout_callback(btstack_timer_source_t * ts); 196 #endif 197 #ifdef ENABLE_L2CAP_ENHANCED_CREDIT_BASED_FLOW_CONTROL_MODE 198 static int l2cap_ecbm_signaling_handler_dispatch(hci_con_handle_t handle, uint16_t signaling_cid, uint8_t * command, uint8_t sig_id); 199 #endif 200 201 // l2cap_fixed_channel_t entries 202 #ifdef ENABLE_BLE 203 static l2cap_fixed_channel_t l2cap_fixed_channel_att; 204 static l2cap_fixed_channel_t l2cap_fixed_channel_sm; 205 #endif 206 #ifdef ENABLE_CLASSIC 207 static l2cap_fixed_channel_t l2cap_fixed_channel_connectionless; 208 #endif 209 210 #ifdef ENABLE_CLASSIC 211 static btstack_linked_list_t l2cap_services; 212 static uint8_t l2cap_require_security_level2_for_outgoing_sdp; 213 static bd_addr_t l2cap_outgoing_classic_addr; 214 #endif 215 216 #ifdef ENABLE_L2CAP_LE_CREDIT_BASED_FLOW_CONTROL_MODE 217 static btstack_linked_list_t l2cap_le_services; 218 #endif 219 220 #ifdef ENABLE_L2CAP_ENHANCED_CREDIT_BASED_FLOW_CONTROL_MODE 221 static btstack_linked_list_t l2cap_enhanced_services; 222 static uint16_t l2cap_enhanced_mps_min; 223 static uint16_t l2cap_enhanced_mps_max; 224 #endif 225 226 // single list of channels for connection-oriented channels (basic, ertm, cbm, ecbf) Classic Connectionless, ATT, and SM 227 static btstack_linked_list_t l2cap_channels; 228 #ifdef L2CAP_USES_CHANNELS 229 // next channel id for new connections 230 static uint16_t l2cap_local_source_cid; 231 #endif 232 // next signaling sequence number 233 static uint8_t l2cap_sig_seq_nr; 234 235 // used to cache l2cap rejects, echo, and informational requests 236 static l2cap_signaling_response_t l2cap_signaling_responses[NR_PENDING_SIGNALING_RESPONSES]; 237 static int l2cap_signaling_responses_pending; 238 static btstack_packet_callback_registration_t l2cap_hci_event_callback_registration; 239 240 static bool l2cap_call_notify_channel_in_run; 241 242 #ifdef ENABLE_BLE 243 // only used for connection parameter update events 244 static uint16_t l2cap_le_custom_max_mtu; 245 #endif 246 247 /* callbacks for events */ 248 static btstack_linked_list_t l2cap_event_handlers; 249 250 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 251 252 // enable for testing 253 // #define L2CAP_ERTM_SIMULATE_FCS_ERROR_INTERVAL 16 254 255 /* 256 * CRC lookup table for generator polynom D^16 + D^15 + D^2 + 1 257 */ 258 static const uint16_t crc16_table[256] = { 259 0x0000, 0xc0c1, 0xc181, 0x0140, 0xc301, 0x03c0, 0x0280, 0xc241, 0xc601, 0x06c0, 0x0780, 0xc741, 0x0500, 0xc5c1, 0xc481, 0x0440, 260 0xcc01, 0x0cc0, 0x0d80, 0xcd41, 0x0f00, 0xcfc1, 0xce81, 0x0e40, 0x0a00, 0xcac1, 0xcb81, 0x0b40, 0xc901, 0x09c0, 0x0880, 0xc841, 261 0xd801, 0x18c0, 0x1980, 0xd941, 0x1b00, 0xdbc1, 0xda81, 0x1a40, 0x1e00, 0xdec1, 0xdf81, 0x1f40, 0xdd01, 0x1dc0, 0x1c80, 0xdc41, 262 0x1400, 0xd4c1, 0xd581, 0x1540, 0xd701, 0x17c0, 0x1680, 0xd641, 0xd201, 0x12c0, 0x1380, 0xd341, 0x1100, 0xd1c1, 0xd081, 0x1040, 263 0xf001, 0x30c0, 0x3180, 0xf141, 0x3300, 0xf3c1, 0xf281, 0x3240, 0x3600, 0xf6c1, 0xf781, 0x3740, 0xf501, 0x35c0, 0x3480, 0xf441, 264 0x3c00, 0xfcc1, 0xfd81, 0x3d40, 0xff01, 0x3fc0, 0x3e80, 0xfe41, 0xfa01, 0x3ac0, 0x3b80, 0xfb41, 0x3900, 0xf9c1, 0xf881, 0x3840, 265 0x2800, 0xe8c1, 0xe981, 0x2940, 0xeb01, 0x2bc0, 0x2a80, 0xea41, 0xee01, 0x2ec0, 0x2f80, 0xef41, 0x2d00, 0xedc1, 0xec81, 0x2c40, 266 0xe401, 0x24c0, 0x2580, 0xe541, 0x2700, 0xe7c1, 0xe681, 0x2640, 0x2200, 0xe2c1, 0xe381, 0x2340, 0xe101, 0x21c0, 0x2080, 0xe041, 267 0xa001, 0x60c0, 0x6180, 0xa141, 0x6300, 0xa3c1, 0xa281, 0x6240, 0x6600, 0xa6c1, 0xa781, 0x6740, 0xa501, 0x65c0, 0x6480, 0xa441, 268 0x6c00, 0xacc1, 0xad81, 0x6d40, 0xaf01, 0x6fc0, 0x6e80, 0xae41, 0xaa01, 0x6ac0, 0x6b80, 0xab41, 0x6900, 0xa9c1, 0xa881, 0x6840, 269 0x7800, 0xb8c1, 0xb981, 0x7940, 0xbb01, 0x7bc0, 0x7a80, 0xba41, 0xbe01, 0x7ec0, 0x7f80, 0xbf41, 0x7d00, 0xbdc1, 0xbc81, 0x7c40, 270 0xb401, 0x74c0, 0x7580, 0xb541, 0x7700, 0xb7c1, 0xb681, 0x7640, 0x7200, 0xb2c1, 0xb381, 0x7340, 0xb101, 0x71c0, 0x7080, 0xb041, 271 0x5000, 0x90c1, 0x9181, 0x5140, 0x9301, 0x53c0, 0x5280, 0x9241, 0x9601, 0x56c0, 0x5780, 0x9741, 0x5500, 0x95c1, 0x9481, 0x5440, 272 0x9c01, 0x5cc0, 0x5d80, 0x9d41, 0x5f00, 0x9fc1, 0x9e81, 0x5e40, 0x5a00, 0x9ac1, 0x9b81, 0x5b40, 0x9901, 0x59c0, 0x5880, 0x9841, 273 0x8801, 0x48c0, 0x4980, 0x8941, 0x4b00, 0x8bc1, 0x8a81, 0x4a40, 0x4e00, 0x8ec1, 0x8f81, 0x4f40, 0x8d01, 0x4dc0, 0x4c80, 0x8c41, 274 0x4400, 0x84c1, 0x8581, 0x4540, 0x8701, 0x47c0, 0x4680, 0x8641, 0x8201, 0x42c0, 0x4380, 0x8341, 0x4100, 0x81c1, 0x8081, 0x4040, 275 }; 276 277 static uint16_t crc16_calc(uint8_t * data, uint16_t len){ 278 uint16_t crc = 0; // initial value = 0 279 while (len--){ 280 crc = (crc >> 8) ^ crc16_table[ (crc ^ ((uint16_t) *data++)) & 0x00FF ]; 281 } 282 return crc; 283 } 284 285 static inline uint16_t l2cap_encanced_control_field_for_information_frame(uint8_t tx_seq, int final, uint8_t req_seq, l2cap_segmentation_and_reassembly_t sar){ 286 return (((uint16_t) sar) << 14) | (req_seq << 8) | (final << 7) | (tx_seq << 1) | 0; 287 } 288 289 static inline uint16_t l2cap_encanced_control_field_for_supevisor_frame(l2cap_supervisory_function_t supervisory_function, int poll, int final, uint8_t req_seq){ 290 return (req_seq << 8) | (final << 7) | (poll << 4) | (((int) supervisory_function) << 2) | 1; 291 } 292 293 static int l2cap_next_ertm_seq_nr(int seq_nr){ 294 return (seq_nr + 1) & 0x3f; 295 } 296 297 static bool l2cap_ertm_can_store_packet_now(l2cap_channel_t * channel){ 298 // get num free tx buffers 299 int num_free_tx_buffers = channel->num_tx_buffers - channel->num_stored_tx_frames; 300 // calculate num tx buffers for remote MTU 301 int num_tx_buffers_for_max_remote_mtu; 302 uint16_t effective_mps = btstack_min(channel->remote_mps, channel->local_mps); 303 if (channel->remote_mtu <= effective_mps){ 304 // MTU fits into single packet 305 num_tx_buffers_for_max_remote_mtu = 1; 306 } else { 307 // include SDU Length 308 num_tx_buffers_for_max_remote_mtu = (channel->remote_mtu + 2 + (effective_mps - 1)) / effective_mps; 309 } 310 log_debug("num_free_tx_buffers %u, num_tx_buffers_for_max_remote_mtu %u", num_free_tx_buffers, num_tx_buffers_for_max_remote_mtu); 311 return num_tx_buffers_for_max_remote_mtu <= num_free_tx_buffers; 312 } 313 314 static void l2cap_ertm_retransmit_unacknowleded_frames(l2cap_channel_t * l2cap_channel){ 315 log_info("Retransmit unacknowleged frames"); 316 l2cap_channel->unacked_frames = 0;; 317 l2cap_channel->tx_send_index = l2cap_channel->tx_read_index; 318 } 319 320 static void l2cap_ertm_next_tx_write_index(l2cap_channel_t * channel){ 321 channel->tx_write_index++; 322 if (channel->tx_write_index < channel->num_tx_buffers) return; 323 channel->tx_write_index = 0; 324 } 325 326 static void l2cap_ertm_start_monitor_timer(l2cap_channel_t * channel){ 327 log_info("Start Monitor timer"); 328 btstack_run_loop_remove_timer(&channel->monitor_timer); 329 btstack_run_loop_set_timer_handler(&channel->monitor_timer, &l2cap_ertm_monitor_timeout_callback); 330 btstack_run_loop_set_timer_context(&channel->monitor_timer, channel); 331 btstack_run_loop_set_timer(&channel->monitor_timer, channel->local_monitor_timeout_ms); 332 btstack_run_loop_add_timer(&channel->monitor_timer); 333 } 334 335 static void l2cap_ertm_stop_monitor_timer(l2cap_channel_t * channel){ 336 log_info("Stop Monitor timer"); 337 btstack_run_loop_remove_timer(&channel->monitor_timer); 338 } 339 340 static void l2cap_ertm_start_retransmission_timer(l2cap_channel_t * channel){ 341 log_info("Start Retransmission timer"); 342 btstack_run_loop_remove_timer(&channel->retransmission_timer); 343 btstack_run_loop_set_timer_handler(&channel->retransmission_timer, &l2cap_ertm_retransmission_timeout_callback); 344 btstack_run_loop_set_timer_context(&channel->retransmission_timer, channel); 345 btstack_run_loop_set_timer(&channel->retransmission_timer, channel->local_retransmission_timeout_ms); 346 btstack_run_loop_add_timer(&channel->retransmission_timer); 347 } 348 349 static void l2cap_ertm_stop_retransmission_timer(l2cap_channel_t * l2cap_channel){ 350 log_info("Stop Retransmission timer"); 351 btstack_run_loop_remove_timer(&l2cap_channel->retransmission_timer); 352 } 353 354 static void l2cap_ertm_monitor_timeout_callback(btstack_timer_source_t * ts){ 355 log_info("Monitor timeout"); 356 l2cap_channel_t * l2cap_channel = (l2cap_channel_t *) btstack_run_loop_get_timer_context(ts); 357 358 // TODO: we assume that it's the oldest packet 359 l2cap_ertm_tx_packet_state_t * tx_state; 360 tx_state = &l2cap_channel->tx_packets_state[l2cap_channel->tx_read_index]; 361 362 // check retry count 363 if (tx_state->retry_count < l2cap_channel->remote_max_transmit){ 364 // increment retry count 365 tx_state->retry_count++; 366 367 // start retransmit 368 l2cap_ertm_retransmit_unacknowleded_frames(l2cap_channel); 369 370 // start monitor timer 371 l2cap_ertm_start_monitor_timer(l2cap_channel); 372 373 // send RR/P=1 374 l2cap_channel->send_supervisor_frame_receiver_ready_poll = 1; 375 } else { 376 log_info("Monitor timer expired & retry count >= max transmit -> disconnect"); 377 l2cap_channel->state = L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST; 378 } 379 l2cap_run(); 380 } 381 382 static void l2cap_ertm_retransmission_timeout_callback(btstack_timer_source_t * ts){ 383 log_info("Retransmission timeout"); 384 l2cap_channel_t * l2cap_channel = (l2cap_channel_t *) btstack_run_loop_get_timer_context(ts); 385 386 // TODO: we assume that it's the oldest packet 387 l2cap_ertm_tx_packet_state_t * tx_state; 388 tx_state = &l2cap_channel->tx_packets_state[l2cap_channel->tx_read_index]; 389 390 // set retry count = 1 391 tx_state->retry_count = 1; 392 393 // start retransmit 394 l2cap_ertm_retransmit_unacknowleded_frames(l2cap_channel); 395 396 // start monitor timer 397 l2cap_ertm_start_monitor_timer(l2cap_channel); 398 399 // send RR/P=1 400 l2cap_channel->send_supervisor_frame_receiver_ready_poll = 1; 401 l2cap_run(); 402 } 403 404 static int l2cap_ertm_send_information_frame(l2cap_channel_t * channel, int index, int final){ 405 l2cap_ertm_tx_packet_state_t * tx_state = &channel->tx_packets_state[index]; 406 hci_reserve_packet_buffer(); 407 uint8_t *acl_buffer = hci_get_outgoing_packet_buffer(); 408 uint16_t control = l2cap_encanced_control_field_for_information_frame(tx_state->tx_seq, final, channel->req_seq, tx_state->sar); 409 log_info("I-Frame: control 0x%04x", control); 410 little_endian_store_16(acl_buffer, 8, control); 411 (void)memcpy(&acl_buffer[8 + 2], 412 &channel->tx_packets_data[index * channel->local_mps], 413 tx_state->len); 414 // (re-)start retransmission timer on 415 l2cap_ertm_start_retransmission_timer(channel); 416 // send 417 return l2cap_send_prepared(channel->local_cid, 2 + tx_state->len); 418 } 419 420 static void l2cap_ertm_store_fragment(l2cap_channel_t * channel, l2cap_segmentation_and_reassembly_t sar, uint16_t sdu_length, uint8_t * data, uint16_t len){ 421 // get next index for storing packets 422 int index = channel->tx_write_index; 423 424 l2cap_ertm_tx_packet_state_t * tx_state = &channel->tx_packets_state[index]; 425 tx_state->tx_seq = channel->next_tx_seq; 426 tx_state->sar = sar; 427 tx_state->retry_count = 0; 428 429 uint8_t * tx_packet = &channel->tx_packets_data[index * channel->local_mps]; 430 log_debug("index %u, local mps %u, remote mps %u, packet tx %p, len %u", index, channel->local_mps, channel->remote_mps, tx_packet, len); 431 int pos = 0; 432 if (sar == L2CAP_SEGMENTATION_AND_REASSEMBLY_START_OF_L2CAP_SDU){ 433 little_endian_store_16(tx_packet, 0, sdu_length); 434 pos += 2; 435 } 436 (void)memcpy(&tx_packet[pos], data, len); 437 tx_state->len = pos + len; 438 439 // update 440 channel->num_stored_tx_frames++; 441 channel->next_tx_seq = l2cap_next_ertm_seq_nr(channel->next_tx_seq); 442 l2cap_ertm_next_tx_write_index(channel); 443 444 log_info("l2cap_ertm_store_fragment: tx_read_index %u, tx_write_index %u, num stored %u", channel->tx_read_index, channel->tx_write_index, channel->num_stored_tx_frames); 445 446 } 447 448 static uint8_t l2cap_ertm_send(l2cap_channel_t * channel, uint8_t * data, uint16_t len){ 449 if (len > channel->remote_mtu){ 450 log_error("l2cap_ertm_send cid 0x%02x, data length exceeds remote MTU.", channel->local_cid); 451 return L2CAP_DATA_LEN_EXCEEDS_REMOTE_MTU; 452 } 453 454 if (!l2cap_ertm_can_store_packet_now(channel)){ 455 log_error("l2cap_ertm_send cid 0x%02x, fragment store full", channel->local_cid); 456 return BTSTACK_ACL_BUFFERS_FULL; 457 } 458 459 // check if it needs to get fragmented 460 uint16_t effective_mps = btstack_min(channel->remote_mps, channel->local_mps); 461 if (len > effective_mps){ 462 // fragmentation needed. 463 l2cap_segmentation_and_reassembly_t sar = L2CAP_SEGMENTATION_AND_REASSEMBLY_START_OF_L2CAP_SDU; 464 int chunk_len; 465 while (len){ 466 switch (sar){ 467 case L2CAP_SEGMENTATION_AND_REASSEMBLY_START_OF_L2CAP_SDU: 468 chunk_len = effective_mps - 2; // sdu_length 469 l2cap_ertm_store_fragment(channel, sar, len, data, chunk_len); 470 len -= chunk_len; 471 sar = L2CAP_SEGMENTATION_AND_REASSEMBLY_CONTINUATION_OF_L2CAP_SDU; 472 break; 473 case L2CAP_SEGMENTATION_AND_REASSEMBLY_CONTINUATION_OF_L2CAP_SDU: 474 chunk_len = effective_mps; 475 if (chunk_len >= len){ 476 sar = L2CAP_SEGMENTATION_AND_REASSEMBLY_END_OF_L2CAP_SDU; 477 chunk_len = len; 478 } 479 l2cap_ertm_store_fragment(channel, sar, len, data, chunk_len); 480 len -= chunk_len; 481 break; 482 default: 483 break; 484 } 485 } 486 487 } else { 488 l2cap_ertm_store_fragment(channel, L2CAP_SEGMENTATION_AND_REASSEMBLY_UNSEGMENTED_L2CAP_SDU, 0, data, len); 489 } 490 491 // try to send 492 l2cap_notify_channel_can_send(); 493 return ERROR_CODE_SUCCESS; 494 } 495 496 static uint16_t l2cap_setup_options_ertm_request(l2cap_channel_t * channel, uint8_t * config_options){ 497 int pos = 0; 498 config_options[pos++] = L2CAP_CONFIG_OPTION_TYPE_RETRANSMISSION_AND_FLOW_CONTROL; 499 config_options[pos++] = 9; // length 500 config_options[pos++] = (uint8_t) channel->mode; 501 config_options[pos++] = channel->num_rx_buffers; // == TxWindows size 502 config_options[pos++] = channel->local_max_transmit; 503 little_endian_store_16( config_options, pos, channel->local_retransmission_timeout_ms); 504 pos += 2; 505 little_endian_store_16( config_options, pos, channel->local_monitor_timeout_ms); 506 pos += 2; 507 little_endian_store_16( config_options, pos, channel->local_mps); 508 pos += 2; 509 // 510 config_options[pos++] = L2CAP_CONFIG_OPTION_TYPE_MAX_TRANSMISSION_UNIT; 511 config_options[pos++] = 2; // length 512 little_endian_store_16(config_options, pos, channel->local_mtu); 513 pos += 2; 514 515 // Issue: iOS (e.g. 10.2) uses "No FCS" as default while Core 5.0 specifies "FCS" as default 516 // Workaround: try to actively negotiate FCS option 517 config_options[pos++] = L2CAP_CONFIG_OPTION_TYPE_FRAME_CHECK_SEQUENCE; 518 config_options[pos++] = 1; // length 519 config_options[pos++] = channel->fcs_option; 520 return pos; // 11+4+3=18 521 } 522 523 static uint16_t l2cap_setup_options_ertm_response(l2cap_channel_t * channel, uint8_t * config_options){ 524 int pos = 0; 525 config_options[pos++] = L2CAP_CONFIG_OPTION_TYPE_RETRANSMISSION_AND_FLOW_CONTROL; 526 config_options[pos++] = 9; // length 527 config_options[pos++] = (uint8_t) channel->mode; 528 // less or equal to remote tx window size 529 config_options[pos++] = btstack_min(channel->num_tx_buffers, channel->remote_tx_window_size); 530 // max transmit in response shall be ignored -> use sender values 531 config_options[pos++] = channel->remote_max_transmit; 532 // A value for the Retransmission time-out shall be sent in a positive Configuration Response 533 // and indicates the value that will be used by the sender of the Configuration Response -> use our value 534 little_endian_store_16( config_options, pos, channel->local_retransmission_timeout_ms); 535 pos += 2; 536 // A value for the Monitor time-out shall be sent in a positive Configuration Response 537 // and indicates the value that will be used by the sender of the Configuration Response -> use our value 538 little_endian_store_16( config_options, pos, channel->local_monitor_timeout_ms); 539 pos += 2; 540 // less or equal to remote mps 541 uint16_t effective_mps = btstack_min(channel->remote_mps, channel->local_mps); 542 little_endian_store_16( config_options, pos, effective_mps); 543 pos += 2; 544 // 545 config_options[pos++] = L2CAP_CONFIG_OPTION_TYPE_MAX_TRANSMISSION_UNIT; // MTU 546 config_options[pos++] = 2; // length 547 little_endian_store_16(config_options, pos, channel->remote_mtu); 548 pos += 2; 549 #if 0 550 // 551 config_options[pos++] = L2CAP_CONFIG_OPTION_TYPE_FRAME_CHECK_SEQUENCE; 552 config_options[pos++] = 1; // length 553 config_options[pos++] = channel->fcs_option; 554 #endif 555 return pos; // 11+4=15 556 } 557 558 static int l2cap_ertm_send_supervisor_frame(l2cap_channel_t * channel, uint16_t control){ 559 hci_reserve_packet_buffer(); 560 uint8_t *acl_buffer = hci_get_outgoing_packet_buffer(); 561 log_info("S-Frame: control 0x%04x", control); 562 little_endian_store_16(acl_buffer, 8, control); 563 return l2cap_send_prepared(channel->local_cid, 2); 564 } 565 566 static uint8_t l2cap_ertm_validate_local_config(l2cap_ertm_config_t * ertm_config){ 567 568 uint8_t result = ERROR_CODE_SUCCESS; 569 if (ertm_config->max_transmit < 1){ 570 log_error("max_transmit must be >= 1"); 571 result = ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS; 572 } 573 if (ertm_config->retransmission_timeout_ms < 2000){ 574 log_error("retransmission_timeout_ms must be >= 2000 ms"); 575 result = ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS; 576 } 577 if (ertm_config->monitor_timeout_ms < 12000){ 578 log_error("monitor_timeout_ms must be >= 12000 ms"); 579 result = ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS; 580 } 581 if (ertm_config->local_mtu < 48){ 582 log_error("local_mtu must be >= 48"); 583 result = ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS; 584 } 585 if (ertm_config->num_rx_buffers < 1){ 586 log_error("num_rx_buffers must be >= 1"); 587 result = ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS; 588 } 589 if (ertm_config->num_tx_buffers < 1){ 590 log_error("num_rx_buffers must be >= 1"); 591 result = ERROR_CODE_INVALID_HCI_COMMAND_PARAMETERS; 592 } 593 return result; 594 } 595 596 static void l2cap_ertm_configure_channel(l2cap_channel_t * channel, l2cap_ertm_config_t * ertm_config, uint8_t * buffer, uint32_t size){ 597 598 channel->mode = L2CAP_CHANNEL_MODE_ENHANCED_RETRANSMISSION; 599 channel->ertm_mandatory = ertm_config->ertm_mandatory; 600 channel->local_max_transmit = ertm_config->max_transmit; 601 channel->local_retransmission_timeout_ms = ertm_config->retransmission_timeout_ms; 602 channel->local_monitor_timeout_ms = ertm_config->monitor_timeout_ms; 603 channel->local_mtu = ertm_config->local_mtu; 604 channel->num_rx_buffers = ertm_config->num_rx_buffers; 605 channel->num_tx_buffers = ertm_config->num_tx_buffers; 606 607 // align buffer to 16-byte boundary to assert l2cap_ertm_rx_packet_state_t is aligned 608 int bytes_till_alignment = 16 - (((uintptr_t) buffer) & 0x0f); 609 buffer += bytes_till_alignment; 610 size -= bytes_till_alignment; 611 612 // setup state buffers - use void cast to avoid -Wcast-align warning 613 uint32_t pos = 0; 614 channel->rx_packets_state = (l2cap_ertm_rx_packet_state_t *) (void *) &buffer[pos]; 615 pos += ertm_config->num_rx_buffers * sizeof(l2cap_ertm_rx_packet_state_t); 616 channel->tx_packets_state = (l2cap_ertm_tx_packet_state_t *) (void *) &buffer[pos]; 617 pos += ertm_config->num_tx_buffers * sizeof(l2cap_ertm_tx_packet_state_t); 618 619 // setup reassembly buffer 620 channel->reassembly_buffer = &buffer[pos]; 621 pos += ertm_config->local_mtu; 622 623 // divide rest of data equally 624 channel->local_mps = (size - pos) / (ertm_config->num_rx_buffers + ertm_config->num_tx_buffers); 625 log_info("Local MPS: %u", channel->local_mps); 626 channel->rx_packets_data = &buffer[pos]; 627 pos += ertm_config->num_rx_buffers * channel->local_mps; 628 channel->tx_packets_data = &buffer[pos]; 629 630 channel->fcs_option = ertm_config->fcs_option; 631 } 632 633 uint8_t l2cap_ertm_create_channel(btstack_packet_handler_t packet_handler, bd_addr_t address, uint16_t psm, 634 l2cap_ertm_config_t * ertm_config, uint8_t * buffer, uint32_t size, uint16_t * out_local_cid){ 635 636 log_info("l2cap_ertm_create_channel addr %s, psm 0x%x, local mtu %u", bd_addr_to_str(address), psm, ertm_config->local_mtu); 637 638 // validate local config 639 uint8_t result = l2cap_ertm_validate_local_config(ertm_config); 640 if (result) return result; 641 642 // determine security level based on psm 643 const gap_security_level_t security_level = l2cap_security_level_0_allowed_for_PSM(psm) ? LEVEL_0 : gap_get_security_level(); 644 645 l2cap_channel_t * channel = l2cap_create_channel_entry(packet_handler, L2CAP_CHANNEL_TYPE_CLASSIC, address, BD_ADDR_TYPE_ACL, psm, ertm_config->local_mtu, security_level); 646 if (!channel) { 647 return BTSTACK_MEMORY_ALLOC_FAILED; 648 } 649 650 // configure ERTM 651 l2cap_ertm_configure_channel(channel, ertm_config, buffer, size); 652 653 // add to connections list 654 btstack_linked_list_add_tail(&l2cap_channels, (btstack_linked_item_t *) channel); 655 656 // store local_cid 657 if (out_local_cid){ 658 *out_local_cid = channel->local_cid; 659 } 660 661 // check if hci connection is already usable 662 hci_connection_t * conn = hci_connection_for_bd_addr_and_type(address, BD_ADDR_TYPE_ACL); 663 if (conn){ 664 log_info("l2cap_create_channel, hci connection already exists"); 665 l2cap_handle_connection_complete(conn->con_handle, channel); 666 // check if remote supported fearures are already received 667 if (hci_remote_features_available(conn->con_handle)) { 668 l2cap_handle_remote_supported_features_received(channel); 669 } else { 670 hci_remote_features_query(conn->con_handle); 671 }; 672 } 673 674 l2cap_run(); 675 676 return 0; 677 } 678 679 static void l2cap_ertm_notify_channel_can_send(l2cap_channel_t * channel){ 680 if (l2cap_ertm_can_store_packet_now(channel)){ 681 channel->waiting_for_can_send_now = 0; 682 l2cap_emit_can_send_now(channel->packet_handler, channel->local_cid); 683 } 684 } 685 686 uint8_t l2cap_ertm_accept_connection(uint16_t local_cid, l2cap_ertm_config_t * ertm_config, uint8_t * buffer, uint32_t size){ 687 688 log_info("l2cap_ertm_accept_connection local_cid 0x%x", local_cid); 689 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 690 if (!channel) { 691 log_error("l2cap_accept_connection called but local_cid 0x%x not found", local_cid); 692 return L2CAP_LOCAL_CID_DOES_NOT_EXIST; 693 } 694 695 // validate local config 696 uint8_t result = l2cap_ertm_validate_local_config(ertm_config); 697 if (result) return result; 698 699 // configure L2CAP ERTM 700 l2cap_ertm_configure_channel(channel, ertm_config, buffer, size); 701 702 // already available? 703 hci_connection_t * connection = hci_connection_for_handle(channel->con_handle); 704 btstack_assert(connection != NULL); 705 706 // we need to know if ERTM is supported before sending a config response 707 switch (connection->l2cap_state.information_state){ 708 case L2CAP_INFORMATION_STATE_DONE: 709 l2cap_handle_information_request_complete(connection); 710 break; 711 case L2CAP_INFORMATION_STATE_IDLE: 712 connection->l2cap_state.information_state = L2CAP_INFORMATION_STATE_W2_SEND_EXTENDED_FEATURE_REQUEST; 713 /* fall through */ 714 default: 715 channel->state = L2CAP_STATE_WAIT_INCOMING_EXTENDED_FEATURES; 716 break; 717 } 718 719 l2cap_run(); 720 721 return ERROR_CODE_SUCCESS; 722 } 723 724 uint8_t l2cap_ertm_decline_connection(uint16_t local_cid){ 725 l2cap_decline_connection(local_cid); 726 return ERROR_CODE_SUCCESS; 727 } 728 729 uint8_t l2cap_ertm_set_busy(uint16_t local_cid){ 730 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid( local_cid); 731 if (!channel) { 732 log_error( "l2cap_decline_connection called but local_cid 0x%x not found", local_cid); 733 return L2CAP_LOCAL_CID_DOES_NOT_EXIST; 734 } 735 if (!channel->local_busy){ 736 channel->local_busy = 1; 737 channel->send_supervisor_frame_receiver_not_ready = 1; 738 l2cap_run(); 739 } 740 return ERROR_CODE_SUCCESS; 741 } 742 743 uint8_t l2cap_ertm_set_ready(uint16_t local_cid){ 744 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid( local_cid); 745 if (!channel) { 746 log_error( "l2cap_decline_connection called but local_cid 0x%x not found", local_cid); 747 return L2CAP_LOCAL_CID_DOES_NOT_EXIST; 748 } 749 if (channel->local_busy){ 750 channel->local_busy = 0; 751 channel->send_supervisor_frame_receiver_ready_poll = 1; 752 l2cap_run(); 753 } 754 return ERROR_CODE_SUCCESS; 755 } 756 757 // Process-ReqSeq 758 static void l2cap_ertm_process_req_seq(l2cap_channel_t * l2cap_channel, uint8_t req_seq){ 759 int num_buffers_acked = 0; 760 l2cap_ertm_tx_packet_state_t * tx_state; 761 log_info("l2cap_ertm_process_req_seq: tx_read_index %u, tx_write_index %u, req_seq %u", l2cap_channel->tx_read_index, l2cap_channel->tx_write_index, req_seq); 762 while (true){ 763 764 // no unack packets left 765 if (l2cap_channel->unacked_frames == 0) { 766 // stop retransmission timer 767 l2cap_ertm_stop_retransmission_timer(l2cap_channel); 768 break; 769 } 770 771 tx_state = &l2cap_channel->tx_packets_state[l2cap_channel->tx_read_index]; 772 // calc delta 773 int delta = (req_seq - tx_state->tx_seq) & 0x03f; 774 if (delta == 0) break; // all packets acknowledged 775 if (delta > l2cap_channel->remote_tx_window_size) break; 776 777 num_buffers_acked++; 778 l2cap_channel->num_stored_tx_frames--; 779 l2cap_channel->unacked_frames--; 780 log_info("RR seq %u => packet with tx_seq %u done", req_seq, tx_state->tx_seq); 781 782 l2cap_channel->tx_read_index++; 783 if (l2cap_channel->tx_read_index >= l2cap_channel->num_rx_buffers){ 784 l2cap_channel->tx_read_index = 0; 785 } 786 } 787 if (num_buffers_acked){ 788 log_info("num_buffers_acked %u", num_buffers_acked); 789 l2cap_ertm_notify_channel_can_send(l2cap_channel); 790 } 791 } 792 793 static l2cap_ertm_tx_packet_state_t * l2cap_ertm_get_tx_state(l2cap_channel_t * l2cap_channel, uint8_t tx_seq){ 794 int i; 795 for (i=0;i<l2cap_channel->num_tx_buffers;i++){ 796 l2cap_ertm_tx_packet_state_t * tx_state = &l2cap_channel->tx_packets_state[i]; 797 if (tx_state->tx_seq == tx_seq) return tx_state; 798 } 799 return NULL; 800 } 801 802 // @param delta number of frames in the future, >= 1 803 // @assumption size <= l2cap_channel->local_mps (checked in l2cap_acl_classic_handler) 804 static void l2cap_ertm_handle_out_of_sequence_sdu(l2cap_channel_t * l2cap_channel, l2cap_segmentation_and_reassembly_t sar, int delta, const uint8_t * payload, uint16_t size){ 805 log_info("Store SDU with delta %u", delta); 806 // get rx state for packet to store 807 int index = l2cap_channel->rx_store_index + delta - 1; 808 if (index > l2cap_channel->num_rx_buffers){ 809 index -= l2cap_channel->num_rx_buffers; 810 } 811 log_info("Index of packet to store %u", index); 812 l2cap_ertm_rx_packet_state_t * rx_state = &l2cap_channel->rx_packets_state[index]; 813 // check if buffer is free 814 if (rx_state->valid){ 815 log_error("Packet buffer already used"); 816 return; 817 } 818 rx_state->valid = 1; 819 rx_state->sar = sar; 820 rx_state->len = size; 821 uint8_t * rx_buffer = &l2cap_channel->rx_packets_data[index]; 822 (void)memcpy(rx_buffer, payload, size); 823 } 824 825 // @assumption size <= l2cap_channel->local_mps (checked in l2cap_acl_classic_handler) 826 static void l2cap_ertm_handle_in_sequence_sdu(l2cap_channel_t * l2cap_channel, l2cap_segmentation_and_reassembly_t sar, const uint8_t * payload, uint16_t size){ 827 uint16_t reassembly_sdu_length; 828 switch (sar){ 829 case L2CAP_SEGMENTATION_AND_REASSEMBLY_UNSEGMENTED_L2CAP_SDU: 830 // assert total packet size <= our mtu 831 if (size > l2cap_channel->local_mtu) break; 832 // packet complete -> disapatch 833 l2cap_dispatch_to_channel(l2cap_channel, L2CAP_DATA_PACKET, (uint8_t*) payload, size); 834 break; 835 case L2CAP_SEGMENTATION_AND_REASSEMBLY_START_OF_L2CAP_SDU: 836 // read SDU len 837 reassembly_sdu_length = little_endian_read_16(payload, 0); 838 payload += 2; 839 size -= 2; 840 // assert reassembled size <= our mtu 841 if (reassembly_sdu_length > l2cap_channel->local_mtu) break; 842 // store start segment 843 l2cap_channel->reassembly_sdu_length = reassembly_sdu_length; 844 (void)memcpy(&l2cap_channel->reassembly_buffer[0], payload, size); 845 l2cap_channel->reassembly_pos = size; 846 break; 847 case L2CAP_SEGMENTATION_AND_REASSEMBLY_CONTINUATION_OF_L2CAP_SDU: 848 // assert size of reassembled data <= our mtu 849 if (l2cap_channel->reassembly_pos + size > l2cap_channel->local_mtu) break; 850 // store continuation segment 851 (void)memcpy(&l2cap_channel->reassembly_buffer[l2cap_channel->reassembly_pos], 852 payload, size); 853 l2cap_channel->reassembly_pos += size; 854 break; 855 case L2CAP_SEGMENTATION_AND_REASSEMBLY_END_OF_L2CAP_SDU: 856 // assert size of reassembled data <= our mtu 857 if (l2cap_channel->reassembly_pos + size > l2cap_channel->local_mtu) break; 858 // store continuation segment 859 (void)memcpy(&l2cap_channel->reassembly_buffer[l2cap_channel->reassembly_pos], 860 payload, size); 861 l2cap_channel->reassembly_pos += size; 862 // assert size of reassembled data matches announced sdu length 863 if (l2cap_channel->reassembly_pos != l2cap_channel->reassembly_sdu_length) break; 864 // packet complete -> disapatch 865 l2cap_dispatch_to_channel(l2cap_channel, L2CAP_DATA_PACKET, l2cap_channel->reassembly_buffer, l2cap_channel->reassembly_pos); 866 l2cap_channel->reassembly_pos = 0; 867 break; 868 default: 869 btstack_assert(false); 870 break; 871 } 872 } 873 874 static void l2cap_ertm_channel_send_information_frame(l2cap_channel_t * channel){ 875 channel->unacked_frames++; 876 int index = channel->tx_send_index; 877 channel->tx_send_index++; 878 if (channel->tx_send_index >= channel->num_tx_buffers){ 879 channel->tx_send_index = 0; 880 } 881 l2cap_ertm_send_information_frame(channel, index, 0); // final = 0 882 } 883 884 #endif 885 886 #ifdef L2CAP_USES_CHANNELS 887 static uint16_t l2cap_next_local_cid(void){ 888 do { 889 if (l2cap_local_source_cid == 0xfffeu) { 890 l2cap_local_source_cid = 0x40; 891 } else { 892 l2cap_local_source_cid++; 893 } 894 } while (l2cap_get_channel_for_local_cid(l2cap_local_source_cid) != NULL); 895 return l2cap_local_source_cid; 896 } 897 #endif 898 899 static uint8_t l2cap_next_sig_id(void){ 900 if (l2cap_sig_seq_nr == 0xffu) { 901 l2cap_sig_seq_nr = 1; 902 } else { 903 l2cap_sig_seq_nr++; 904 } 905 return l2cap_sig_seq_nr; 906 } 907 908 void l2cap_init(void){ 909 #ifdef L2CAP_USES_CHANNELS 910 l2cap_local_source_cid = 0x40; 911 #endif 912 l2cap_sig_seq_nr = 0xff; 913 914 #ifdef ENABLE_CLASSIC 915 // Setup Connectionless Channel 916 l2cap_fixed_channel_connectionless.local_cid = L2CAP_CID_CONNECTIONLESS_CHANNEL; 917 l2cap_fixed_channel_connectionless.channel_type = L2CAP_CHANNEL_TYPE_CONNECTIONLESS; 918 btstack_linked_list_add(&l2cap_channels, (btstack_linked_item_t *) &l2cap_fixed_channel_connectionless); 919 #endif 920 921 #ifdef ENABLE_BLE 922 // Setup fixed ATT Channel 923 l2cap_fixed_channel_att.local_cid = L2CAP_CID_ATTRIBUTE_PROTOCOL; 924 l2cap_fixed_channel_att.channel_type = L2CAP_CHANNEL_TYPE_FIXED; 925 btstack_linked_list_add(&l2cap_channels, (btstack_linked_item_t *) &l2cap_fixed_channel_att); 926 927 // Setup fixed SM Channel 928 l2cap_fixed_channel_sm.local_cid = L2CAP_CID_SECURITY_MANAGER_PROTOCOL; 929 l2cap_fixed_channel_sm.channel_type = L2CAP_CHANNEL_TYPE_FIXED; 930 btstack_linked_list_add(&l2cap_channels, (btstack_linked_item_t *) &l2cap_fixed_channel_sm); 931 #endif 932 933 #ifdef ENABLE_L2CAP_ENHANCED_CREDIT_BASED_FLOW_CONTROL_MODE 934 l2cap_enhanced_mps_min = 0x0001; 935 l2cap_enhanced_mps_max = 0xffff; 936 #endif 937 938 // 939 // register callback with HCI 940 // 941 l2cap_hci_event_callback_registration.callback = &l2cap_hci_event_handler; 942 hci_add_event_handler(&l2cap_hci_event_callback_registration); 943 944 hci_register_acl_packet_handler(&l2cap_acl_handler); 945 946 #ifndef ENABLE_EXPLICIT_CONNECTABLE_MODE_CONTROL 947 #ifdef ENABLE_CLASSIC 948 gap_connectable_control(0); // no services yet 949 #endif 950 #endif 951 } 952 953 /** 954 * @brief De-Init L2CAP 955 */ 956 void l2cap_deinit(void){ 957 l2cap_channels = NULL; 958 l2cap_signaling_responses_pending = 0; 959 #ifdef ENABLE_CLASSIC 960 l2cap_require_security_level2_for_outgoing_sdp = 0; 961 (void)memset(&l2cap_fixed_channel_connectionless, 0, sizeof(l2cap_fixed_channel_connectionless)); 962 l2cap_services = NULL; 963 (void)memset(l2cap_outgoing_classic_addr, 0, 6); 964 #endif 965 #ifdef ENABLE_BLE 966 l2cap_le_custom_max_mtu = 0; 967 (void)memset(&l2cap_fixed_channel_att, 0, sizeof(l2cap_fixed_channel_att)); 968 (void)memset(&l2cap_fixed_channel_sm, 0, sizeof(l2cap_fixed_channel_sm)); 969 #endif 970 #ifdef ENABLE_L2CAP_LE_CREDIT_BASED_FLOW_CONTROL_MODE 971 l2cap_le_services = NULL; 972 #endif 973 #ifdef ENABLE_L2CAP_ENHANCED_CREDIT_BASED_FLOW_CONTROL_MODE 974 l2cap_enhanced_services = NULL; 975 #endif 976 l2cap_event_handlers = NULL; 977 } 978 979 void l2cap_add_event_handler(btstack_packet_callback_registration_t * callback_handler){ 980 btstack_linked_list_add_tail(&l2cap_event_handlers, (btstack_linked_item_t*) callback_handler); 981 } 982 983 void l2cap_remove_event_handler(btstack_packet_callback_registration_t * callback_handler){ 984 btstack_linked_list_remove(&l2cap_event_handlers, (btstack_linked_item_t*) callback_handler); 985 } 986 987 static void l2cap_emit_event(uint8_t *event, uint16_t size) { 988 hci_dump_packet( HCI_EVENT_PACKET, 0, event, size); 989 // dispatch to all event handlers 990 btstack_linked_list_iterator_t it; 991 btstack_linked_list_iterator_init(&it, &l2cap_event_handlers); 992 while (btstack_linked_list_iterator_has_next(&it)){ 993 btstack_packet_callback_registration_t * entry = (btstack_packet_callback_registration_t*) btstack_linked_list_iterator_next(&it); 994 entry->callback(HCI_EVENT_PACKET, 0, event, size); 995 } 996 } 997 998 void l2cap_request_can_send_fix_channel_now_event(hci_con_handle_t con_handle, uint16_t channel_id){ 999 UNUSED(con_handle); // ok: there is no con handle 1000 1001 l2cap_fixed_channel_t * channel = l2cap_fixed_channel_for_channel_id(channel_id); 1002 if (!channel) return; 1003 channel->waiting_for_can_send_now = 1; 1004 l2cap_notify_channel_can_send(); 1005 } 1006 1007 bool l2cap_can_send_fixed_channel_packet_now(hci_con_handle_t con_handle, uint16_t channel_id){ 1008 UNUSED(channel_id); // ok: only depends on Controller LE buffers 1009 1010 return hci_can_send_acl_packet_now(con_handle); 1011 } 1012 1013 uint8_t *l2cap_get_outgoing_buffer(void){ 1014 return hci_get_outgoing_packet_buffer() + COMPLETE_L2CAP_HEADER; // 8 bytes 1015 } 1016 1017 // only for L2CAP Basic Channels 1018 bool l2cap_reserve_packet_buffer(void){ 1019 return hci_reserve_packet_buffer(); 1020 } 1021 1022 // only for L2CAP Basic Channels 1023 void l2cap_release_packet_buffer(void){ 1024 hci_release_packet_buffer(); 1025 } 1026 1027 static void l2cap_setup_header(uint8_t * acl_buffer, hci_con_handle_t con_handle, uint8_t packet_boundary, uint16_t remote_cid, uint16_t len){ 1028 // 0 - Connection handle : PB=pb : BC=00 1029 little_endian_store_16(acl_buffer, 0u, con_handle | (packet_boundary << 12u) | (0u << 14u)); 1030 // 2 - ACL length 1031 little_endian_store_16(acl_buffer, 2u, len + 4u); 1032 // 4 - L2CAP packet length 1033 little_endian_store_16(acl_buffer, 4u, len + 0u); 1034 // 6 - L2CAP channel DEST 1035 little_endian_store_16(acl_buffer, 6, remote_cid); 1036 } 1037 1038 // assumption - only on LE connections 1039 uint8_t l2cap_send_prepared_connectionless(hci_con_handle_t con_handle, uint16_t cid, uint16_t len){ 1040 1041 if (!hci_is_packet_buffer_reserved()){ 1042 log_error("l2cap_send_prepared_connectionless called without reserving packet first"); 1043 return BTSTACK_ACL_BUFFERS_FULL; 1044 } 1045 1046 if (!hci_can_send_prepared_acl_packet_now(con_handle)){ 1047 log_info("l2cap_send_prepared_connectionless handle 0x%02x, cid 0x%02x, cannot send", con_handle, cid); 1048 return BTSTACK_ACL_BUFFERS_FULL; 1049 } 1050 1051 log_debug("l2cap_send_prepared_connectionless handle %u, cid 0x%02x", con_handle, cid); 1052 1053 uint8_t *acl_buffer = hci_get_outgoing_packet_buffer(); 1054 l2cap_setup_header(acl_buffer, con_handle, 0, cid, len); 1055 // send 1056 return hci_send_acl_packet_buffer(len+8u); 1057 } 1058 1059 // assumption - only on LE connections 1060 uint8_t l2cap_send_connectionless(hci_con_handle_t con_handle, uint16_t cid, uint8_t *data, uint16_t len){ 1061 1062 if (!hci_can_send_acl_packet_now(con_handle)){ 1063 log_info("l2cap_send cid 0x%02x, cannot send", cid); 1064 return BTSTACK_ACL_BUFFERS_FULL; 1065 } 1066 1067 hci_reserve_packet_buffer(); 1068 uint8_t *acl_buffer = hci_get_outgoing_packet_buffer(); 1069 1070 (void)memcpy(&acl_buffer[8], data, len); 1071 1072 return l2cap_send_prepared_connectionless(con_handle, cid, len); 1073 } 1074 1075 static void l2cap_emit_can_send_now(btstack_packet_handler_t packet_handler, uint16_t channel) { 1076 log_debug("L2CAP_EVENT_CHANNEL_CAN_SEND_NOW local_cid 0x%x", channel); 1077 uint8_t event[4]; 1078 event[0] = L2CAP_EVENT_CAN_SEND_NOW; 1079 event[1] = sizeof(event) - 2u; 1080 little_endian_store_16(event, 2, channel); 1081 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 1082 packet_handler(HCI_EVENT_PACKET, channel, event, sizeof(event)); 1083 } 1084 1085 #ifdef L2CAP_USES_CHANNELS 1086 static void l2cap_dispatch_to_channel(l2cap_channel_t *channel, uint8_t type, uint8_t * data, uint16_t size){ 1087 (* (channel->packet_handler))(type, channel->local_cid, data, size); 1088 } 1089 1090 static void l2cap_emit_simple_event_with_cid(l2cap_channel_t * channel, uint8_t event_code){ 1091 uint8_t event[4]; 1092 event[0] = event_code; 1093 event[1] = sizeof(event) - 2u; 1094 little_endian_store_16(event, 2, channel->local_cid); 1095 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 1096 l2cap_dispatch_to_channel(channel, HCI_EVENT_PACKET, event, sizeof(event)); 1097 } 1098 #endif 1099 1100 #ifdef ENABLE_CLASSIC 1101 void l2cap_emit_channel_opened(l2cap_channel_t *channel, uint8_t status) { 1102 log_info("L2CAP_EVENT_CHANNEL_OPENED status 0x%x addr %s handle 0x%x psm 0x%x local_cid 0x%x remote_cid 0x%x local_mtu %u, remote_mtu %u, flush_timeout %u", 1103 status, bd_addr_to_str(channel->address), channel->con_handle, channel->psm, 1104 channel->local_cid, channel->remote_cid, channel->local_mtu, channel->remote_mtu, channel->flush_timeout); 1105 uint8_t event[26]; 1106 event[0] = L2CAP_EVENT_CHANNEL_OPENED; 1107 event[1] = sizeof(event) - 2; 1108 event[2] = status; 1109 reverse_bd_addr(channel->address, &event[3]); 1110 little_endian_store_16(event, 9, channel->con_handle); 1111 little_endian_store_16(event, 11, channel->psm); 1112 little_endian_store_16(event, 13, channel->local_cid); 1113 little_endian_store_16(event, 15, channel->remote_cid); 1114 little_endian_store_16(event, 17, channel->local_mtu); 1115 little_endian_store_16(event, 19, channel->remote_mtu); 1116 little_endian_store_16(event, 21, channel->flush_timeout); 1117 event[23] = (channel->state_var & L2CAP_CHANNEL_STATE_VAR_INCOMING) ? 1 : 0; 1118 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 1119 log_info("ERTM mode %u, fcs enabled %u", channel->mode, channel->fcs_option); 1120 event[24] = channel->mode; 1121 event[25] = channel->fcs_option; 1122 1123 #else 1124 event[24] = L2CAP_CHANNEL_MODE_BASIC; 1125 event[25] = 0; 1126 #endif 1127 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 1128 l2cap_dispatch_to_channel(channel, HCI_EVENT_PACKET, event, sizeof(event)); 1129 } 1130 1131 static void l2cap_emit_incoming_connection(l2cap_channel_t *channel) { 1132 log_info("L2CAP_EVENT_INCOMING_CONNECTION addr %s handle 0x%x psm 0x%x local_cid 0x%x remote_cid 0x%x", 1133 bd_addr_to_str(channel->address), channel->con_handle, channel->psm, channel->local_cid, channel->remote_cid); 1134 uint8_t event[16]; 1135 event[0] = L2CAP_EVENT_INCOMING_CONNECTION; 1136 event[1] = sizeof(event) - 2; 1137 reverse_bd_addr(channel->address, &event[2]); 1138 little_endian_store_16(event, 8, channel->con_handle); 1139 little_endian_store_16(event, 10, channel->psm); 1140 little_endian_store_16(event, 12, channel->local_cid); 1141 little_endian_store_16(event, 14, channel->remote_cid); 1142 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 1143 l2cap_dispatch_to_channel(channel, HCI_EVENT_PACKET, event, sizeof(event)); 1144 } 1145 1146 static void l2cap_handle_channel_open_failed(l2cap_channel_t * channel, uint8_t status){ 1147 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 1148 // emit ertm buffer released, as it's not needed. if in basic mode, it was either not allocated or already released 1149 if (channel->mode == L2CAP_CHANNEL_MODE_ENHANCED_RETRANSMISSION){ 1150 l2cap_emit_simple_event_with_cid(channel, L2CAP_EVENT_ERTM_BUFFER_RELEASED); 1151 } 1152 #endif 1153 l2cap_emit_channel_opened(channel, status); 1154 } 1155 1156 #endif 1157 1158 #ifdef L2CAP_USES_CHANNELS 1159 1160 static void l2cap_emit_channel_closed(l2cap_channel_t *channel) { 1161 log_info("L2CAP_EVENT_CHANNEL_CLOSED local_cid 0x%x", channel->local_cid); 1162 l2cap_emit_simple_event_with_cid(channel, L2CAP_EVENT_CHANNEL_CLOSED); 1163 } 1164 1165 static void l2cap_handle_channel_closed(l2cap_channel_t * channel){ 1166 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 1167 // emit ertm buffer released, as it's not needed anymore. if in basic mode, it was either not allocated or already released 1168 if (channel->mode == L2CAP_CHANNEL_MODE_ENHANCED_RETRANSMISSION){ 1169 l2cap_emit_simple_event_with_cid(channel, L2CAP_EVENT_ERTM_BUFFER_RELEASED); 1170 } 1171 #endif 1172 l2cap_emit_channel_closed(channel); 1173 } 1174 #endif 1175 1176 static l2cap_fixed_channel_t * l2cap_channel_item_by_cid(uint16_t cid){ 1177 btstack_linked_list_iterator_t it; 1178 btstack_linked_list_iterator_init(&it, &l2cap_channels); 1179 while (btstack_linked_list_iterator_has_next(&it)){ 1180 l2cap_fixed_channel_t * channel = (l2cap_fixed_channel_t*) btstack_linked_list_iterator_next(&it); 1181 if (channel->local_cid == cid) { 1182 return channel; 1183 } 1184 } 1185 return NULL; 1186 } 1187 1188 // used for fixed channels in LE (ATT/SM) and Classic (Connectionless Channel). CID < 0x04 1189 static l2cap_fixed_channel_t * l2cap_fixed_channel_for_channel_id(uint16_t local_cid){ 1190 if (local_cid >= 0x40u) return NULL; 1191 return (l2cap_fixed_channel_t*) l2cap_channel_item_by_cid(local_cid); 1192 } 1193 1194 #ifdef L2CAP_USES_CHANNELS 1195 1196 static int l2cap_is_dynamic_channel_type(l2cap_channel_type_t channel_type) { 1197 switch (channel_type) { 1198 case L2CAP_CHANNEL_TYPE_CLASSIC: 1199 case L2CAP_CHANNEL_TYPE_CHANNEL_CBM: 1200 case L2CAP_CHANNEL_TYPE_CHANNEL_ECBM: 1201 return 1; 1202 default: 1203 return 0; 1204 } 1205 } 1206 1207 static l2cap_channel_t * l2cap_get_channel_for_local_cid(uint16_t local_cid){ 1208 if (local_cid < 0x40u) return NULL; 1209 return (l2cap_channel_t*) l2cap_channel_item_by_cid(local_cid); 1210 } 1211 1212 static l2cap_channel_t * l2cap_get_channel_for_local_cid_and_handle(uint16_t local_cid, hci_con_handle_t con_handle){ 1213 if (local_cid < 0x40u) return NULL; 1214 l2cap_channel_t * l2cap_channel = (l2cap_channel_t*) l2cap_channel_item_by_cid(local_cid); 1215 if (l2cap_channel == NULL) return NULL; 1216 if (l2cap_channel->con_handle != con_handle) return NULL; 1217 return l2cap_channel; 1218 } 1219 #endif 1220 1221 #ifdef L2CAP_USES_CREDIT_BASED_CHANNELS 1222 static l2cap_channel_t * l2cap_get_channel_for_remote_handle_and_cid(hci_con_handle_t con_handle, uint16_t remote_cid){ 1223 btstack_linked_list_iterator_t it; 1224 btstack_linked_list_iterator_init(&it, &l2cap_channels); 1225 while (btstack_linked_list_iterator_has_next(&it)){ 1226 l2cap_fixed_channel_t * channel = (l2cap_fixed_channel_t*) btstack_linked_list_iterator_next(&it); 1227 if (!l2cap_is_dynamic_channel_type(channel->channel_type)) continue; 1228 l2cap_channel_t * dynamic_channel = (l2cap_channel_t *) channel; 1229 if (dynamic_channel->con_handle != con_handle) continue; 1230 if (dynamic_channel->remote_cid != remote_cid) continue; 1231 return dynamic_channel; 1232 } 1233 return NULL; 1234 } 1235 #endif 1236 1237 #ifdef ENABLE_CLASSIC 1238 void l2cap_request_can_send_now_event(uint16_t local_cid){ 1239 l2cap_channel_t *channel = l2cap_get_channel_for_local_cid(local_cid); 1240 if (!channel) return; 1241 channel->waiting_for_can_send_now = 1; 1242 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 1243 if (channel->mode == L2CAP_CHANNEL_MODE_ENHANCED_RETRANSMISSION){ 1244 l2cap_ertm_notify_channel_can_send(channel); 1245 return; 1246 } 1247 #endif 1248 l2cap_notify_channel_can_send(); 1249 } 1250 1251 bool l2cap_can_send_packet_now(uint16_t local_cid){ 1252 l2cap_channel_t *channel = l2cap_get_channel_for_local_cid(local_cid); 1253 if (!channel) return false; 1254 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 1255 if (channel->mode == L2CAP_CHANNEL_MODE_ENHANCED_RETRANSMISSION){ 1256 return l2cap_ertm_can_store_packet_now(channel); 1257 } 1258 #endif 1259 return hci_can_send_acl_packet_now(channel->con_handle); 1260 } 1261 1262 bool l2cap_can_send_prepared_packet_now(uint16_t local_cid){ 1263 l2cap_channel_t *channel = l2cap_get_channel_for_local_cid(local_cid); 1264 if (!channel) return false; 1265 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 1266 if (channel->mode == L2CAP_CHANNEL_MODE_ENHANCED_RETRANSMISSION){ 1267 return false; 1268 } 1269 #endif 1270 return hci_can_send_prepared_acl_packet_now(channel->con_handle); 1271 } 1272 1273 uint16_t l2cap_get_remote_mtu_for_local_cid(uint16_t local_cid){ 1274 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 1275 if (channel) { 1276 return channel->remote_mtu; 1277 } 1278 return 0; 1279 } 1280 #endif 1281 1282 #ifdef ENABLE_CLASSIC 1283 // RTX Timer only exist for dynamic channels 1284 static l2cap_channel_t * l2cap_channel_for_rtx_timer(btstack_timer_source_t * ts){ 1285 btstack_linked_list_iterator_t it; 1286 btstack_linked_list_iterator_init(&it, &l2cap_channels); 1287 while (btstack_linked_list_iterator_has_next(&it)){ 1288 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 1289 if (!l2cap_is_dynamic_channel_type(channel->channel_type)) continue; 1290 if (&channel->rtx == ts) { 1291 return channel; 1292 } 1293 } 1294 return NULL; 1295 } 1296 1297 static void l2cap_rtx_timeout(btstack_timer_source_t * ts){ 1298 l2cap_channel_t * channel = l2cap_channel_for_rtx_timer(ts); 1299 if (!channel) return; 1300 1301 log_info("l2cap_rtx_timeout for local cid 0x%02x", channel->local_cid); 1302 1303 // "When terminating the channel, it is not necessary to send a L2CAP_DisconnectReq 1304 // and enter WAIT_DISCONNECT state. Channels can be transitioned directly to the CLOSED state." 1305 // notify client 1306 l2cap_handle_channel_open_failed(channel, L2CAP_CONNECTION_RESPONSE_RESULT_RTX_TIMEOUT); 1307 1308 // discard channel 1309 btstack_linked_list_remove(&l2cap_channels, (btstack_linked_item_t *) channel); 1310 l2cap_free_channel_entry(channel); 1311 } 1312 1313 #endif 1314 1315 #ifdef L2CAP_USES_CHANNELS 1316 static void l2cap_stop_rtx(l2cap_channel_t * channel){ 1317 log_info("l2cap_stop_rtx for local cid 0x%02x", channel->local_cid); 1318 btstack_run_loop_remove_timer(&channel->rtx); 1319 } 1320 #endif 1321 1322 static uint8_t l2cap_send_signaling_packet(hci_con_handle_t handle, uint8_t pb_flags, uint16_t cid, L2CAP_SIGNALING_COMMANDS cmd, int identifier, va_list argptr){ 1323 if (!hci_can_send_acl_packet_now(handle)){ 1324 log_info("l2cap_send_classic_signaling_packet, cannot send"); 1325 return BTSTACK_ACL_BUFFERS_FULL; 1326 } 1327 hci_reserve_packet_buffer(); 1328 uint8_t *acl_buffer = hci_get_outgoing_packet_buffer(); 1329 uint16_t len = l2cap_create_signaling_packet(acl_buffer, handle, pb_flags, cid, cmd, identifier, argptr); 1330 va_end(argptr); 1331 return hci_send_acl_packet_buffer(len); 1332 } 1333 1334 #ifdef L2CAP_USES_CREDIT_BASED_CHANNELS 1335 static int l2cap_send_general_signaling_packet(hci_con_handle_t handle, uint16_t signaling_cid, L2CAP_SIGNALING_COMMANDS cmd, int identifier, ...){ 1336 va_list argptr; 1337 va_start(argptr, identifier); 1338 uint8_t pb_flags = 0x00; 1339 #ifdef ENABLE_CLASSIC 1340 if ((signaling_cid == L2CAP_CID_SIGNALING) && (!hci_non_flushable_packet_boundary_flag_supported())){ 1341 pb_flags = 0x02; 1342 } 1343 #endif 1344 uint8_t result = l2cap_send_signaling_packet(handle, pb_flags, signaling_cid, cmd, identifier, argptr); 1345 va_end(argptr); 1346 return result; 1347 } 1348 #endif 1349 1350 #ifdef ENABLE_CLASSIC 1351 1352 static void l2cap_start_rtx(l2cap_channel_t * channel){ 1353 l2cap_stop_rtx(channel); 1354 log_info("l2cap_start_rtx for local cid 0x%02x", channel->local_cid); 1355 btstack_run_loop_set_timer_handler(&channel->rtx, l2cap_rtx_timeout); 1356 btstack_run_loop_set_timer(&channel->rtx, L2CAP_RTX_TIMEOUT_MS); 1357 btstack_run_loop_add_timer(&channel->rtx); 1358 } 1359 1360 static void l2cap_start_ertx(l2cap_channel_t * channel){ 1361 log_info("l2cap_start_ertx for local cid 0x%02x", channel->local_cid); 1362 l2cap_stop_rtx(channel); 1363 btstack_run_loop_set_timer_handler(&channel->rtx, l2cap_rtx_timeout); 1364 btstack_run_loop_set_timer(&channel->rtx, L2CAP_ERTX_TIMEOUT_MS); 1365 btstack_run_loop_add_timer(&channel->rtx); 1366 } 1367 1368 void l2cap_require_security_level_2_for_outgoing_sdp(void){ 1369 l2cap_require_security_level2_for_outgoing_sdp = 1; 1370 } 1371 1372 static int l2cap_security_level_0_allowed_for_PSM(uint16_t psm){ 1373 return (psm == BLUETOOTH_PSM_SDP) && (!l2cap_require_security_level2_for_outgoing_sdp); 1374 } 1375 1376 static int l2cap_send_classic_signaling_packet(hci_con_handle_t handle, L2CAP_SIGNALING_COMMANDS cmd, int identifier, ...){ 1377 va_list argptr; 1378 va_start(argptr, identifier); 1379 uint8_t pb_flags = hci_non_flushable_packet_boundary_flag_supported() ? 0x00 : 0x02; 1380 uint8_t result = l2cap_send_signaling_packet(handle, pb_flags, L2CAP_CID_SIGNALING, cmd, identifier, argptr); 1381 va_end(argptr); 1382 return result; 1383 } 1384 1385 // assumption - only on Classic connections 1386 // cannot be used for L2CAP ERTM 1387 uint8_t l2cap_send_prepared(uint16_t local_cid, uint16_t len){ 1388 1389 if (!hci_is_packet_buffer_reserved()){ 1390 log_error("l2cap_send_prepared called without reserving packet first"); 1391 return BTSTACK_ACL_BUFFERS_FULL; 1392 } 1393 1394 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 1395 if (!channel) { 1396 log_error("l2cap_send_prepared no channel for cid 0x%02x", local_cid); 1397 return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 1398 } 1399 1400 if (!hci_can_send_prepared_acl_packet_now(channel->con_handle)){ 1401 log_info("l2cap_send_prepared cid 0x%02x, cannot send", local_cid); 1402 return BTSTACK_ACL_BUFFERS_FULL; 1403 } 1404 1405 log_debug("l2cap_send_prepared cid 0x%02x, handle %u, 1 credit used", local_cid, channel->con_handle); 1406 1407 int fcs_size = 0; 1408 1409 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 1410 if (channel->mode == L2CAP_CHANNEL_MODE_ENHANCED_RETRANSMISSION && channel->fcs_option){ 1411 fcs_size = 2; 1412 } 1413 #endif 1414 1415 // set non-flushable packet boundary flag if supported on Controller 1416 uint8_t *acl_buffer = hci_get_outgoing_packet_buffer(); 1417 uint8_t packet_boundary_flag = hci_non_flushable_packet_boundary_flag_supported() ? 0x00 : 0x02; 1418 l2cap_setup_header(acl_buffer, channel->con_handle, packet_boundary_flag, channel->remote_cid, len + fcs_size); 1419 1420 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 1421 if (fcs_size){ 1422 // calculate FCS over l2cap data 1423 uint16_t fcs = crc16_calc(acl_buffer + 4, 4 + len); 1424 log_info("I-Frame: fcs 0x%04x", fcs); 1425 little_endian_store_16(acl_buffer, 8 + len, fcs); 1426 } 1427 #endif 1428 1429 // send 1430 return hci_send_acl_packet_buffer(len+8+fcs_size); 1431 } 1432 1433 // assumption - only on Classic connections 1434 uint8_t l2cap_send(uint16_t local_cid, uint8_t *data, uint16_t len){ 1435 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 1436 if (!channel) { 1437 log_error("l2cap_send no channel for cid 0x%02x", local_cid); 1438 return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 1439 } 1440 1441 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 1442 // send in ERTM 1443 if (channel->mode == L2CAP_CHANNEL_MODE_ENHANCED_RETRANSMISSION){ 1444 return l2cap_ertm_send(channel, data, len); 1445 } 1446 #endif 1447 1448 if (len > channel->remote_mtu){ 1449 log_error("l2cap_send cid 0x%02x, data length exceeds remote MTU.", local_cid); 1450 return L2CAP_DATA_LEN_EXCEEDS_REMOTE_MTU; 1451 } 1452 1453 if (!hci_can_send_acl_packet_now(channel->con_handle)){ 1454 log_info("l2cap_send cid 0x%02x, cannot send", local_cid); 1455 return BTSTACK_ACL_BUFFERS_FULL; 1456 } 1457 1458 hci_reserve_packet_buffer(); 1459 uint8_t *acl_buffer = hci_get_outgoing_packet_buffer(); 1460 (void)memcpy(&acl_buffer[8], data, len); 1461 return l2cap_send_prepared(local_cid, len); 1462 } 1463 1464 int l2cap_send_echo_request(hci_con_handle_t con_handle, uint8_t *data, uint16_t len){ 1465 return l2cap_send_classic_signaling_packet(con_handle, ECHO_REQUEST, l2cap_next_sig_id(), len, data); 1466 } 1467 1468 static inline void channelStateVarSetFlag(l2cap_channel_t *channel, uint16_t flag){ 1469 channel->state_var = channel->state_var | flag; 1470 } 1471 1472 static inline void channelStateVarClearFlag(l2cap_channel_t *channel, uint16_t flag){ 1473 channel->state_var = channel->state_var & ~flag; 1474 } 1475 #endif 1476 1477 1478 #ifdef ENABLE_BLE 1479 static int l2cap_send_le_signaling_packet(hci_con_handle_t handle, L2CAP_SIGNALING_COMMANDS cmd, int identifier, ...){ 1480 va_list argptr; 1481 va_start(argptr, identifier); 1482 uint8_t pb_flags = 0x00; // First non-automatically-flushable packet of a higher layer message 1483 uint8_t result = l2cap_send_signaling_packet(handle, pb_flags, L2CAP_CID_SIGNALING_LE, cmd, identifier, argptr); 1484 va_end(argptr); 1485 return result; 1486 } 1487 #endif 1488 1489 uint16_t l2cap_max_mtu(void){ 1490 return HCI_ACL_PAYLOAD_SIZE - L2CAP_HEADER_SIZE; 1491 } 1492 1493 #ifdef ENABLE_BLE 1494 uint16_t l2cap_max_le_mtu(void){ 1495 if (l2cap_le_custom_max_mtu != 0u) return l2cap_le_custom_max_mtu; 1496 return l2cap_max_mtu(); 1497 } 1498 1499 void l2cap_set_max_le_mtu(uint16_t max_mtu){ 1500 if (max_mtu < l2cap_max_mtu()){ 1501 l2cap_le_custom_max_mtu = max_mtu; 1502 } 1503 } 1504 #endif 1505 1506 #ifdef ENABLE_CLASSIC 1507 1508 static uint16_t l2cap_setup_options_mtu(uint8_t * config_options, uint16_t mtu){ 1509 config_options[0] = L2CAP_CONFIG_OPTION_TYPE_MAX_TRANSMISSION_UNIT; // MTU 1510 config_options[1] = 2; // len param 1511 little_endian_store_16(config_options, 2, mtu); 1512 return 4; 1513 } 1514 1515 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 1516 static int l2cap_ertm_mode(l2cap_channel_t * channel){ 1517 hci_connection_t * connection = hci_connection_for_handle(channel->con_handle); 1518 return ((connection->l2cap_state.information_state == L2CAP_INFORMATION_STATE_DONE) 1519 && (connection->l2cap_state.extended_feature_mask & 0x08)); 1520 } 1521 #endif 1522 1523 static uint16_t l2cap_setup_options_request(l2cap_channel_t * channel, uint8_t * config_options){ 1524 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 1525 // use ERTM options if supported by remote and channel ready to use it 1526 if (l2cap_ertm_mode(channel) && channel->mode == L2CAP_CHANNEL_MODE_ENHANCED_RETRANSMISSION){ 1527 return l2cap_setup_options_ertm_request(channel, config_options); 1528 } 1529 #endif 1530 uint16_t mtu = channel->local_mtu; 1531 return l2cap_setup_options_mtu(config_options, mtu); 1532 } 1533 1534 static uint16_t l2cap_setup_options_mtu_response(l2cap_channel_t * channel, uint8_t * config_options){ 1535 uint16_t mtu = btstack_min(channel->local_mtu, channel->remote_mtu); 1536 return l2cap_setup_options_mtu(config_options, mtu); 1537 } 1538 1539 static uint32_t l2cap_extended_features_mask(void){ 1540 // extended features request supported, features: fixed channels, unicast connectionless data reception 1541 uint32_t features = 0x280; 1542 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 1543 features |= 0x0028; 1544 #endif 1545 return features; 1546 } 1547 #endif 1548 1549 // 1550 #ifdef ENABLE_CLASSIC 1551 1552 // returns true if channel was finalized 1553 static bool l2cap_run_for_classic_channel(l2cap_channel_t * channel){ 1554 1555 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 1556 uint8_t config_options[18]; 1557 #else 1558 uint8_t config_options[10]; 1559 #endif 1560 1561 switch (channel->state){ 1562 1563 case L2CAP_STATE_WAIT_INCOMING_SECURITY_LEVEL_UPDATE: 1564 case L2CAP_STATE_WAIT_CLIENT_ACCEPT_OR_REJECT: 1565 if (!hci_can_send_acl_packet_now(channel->con_handle)) return false; 1566 if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONN_RESP_PEND) { 1567 channelStateVarClearFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONN_RESP_PEND); 1568 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SENT_CONN_RESP_PEND); 1569 l2cap_send_classic_signaling_packet(channel->con_handle, CONNECTION_RESPONSE, channel->remote_sig_id, 1570 channel->local_cid, channel->remote_cid, 1, 0); 1571 } 1572 break; 1573 1574 case L2CAP_STATE_WILL_SEND_CREATE_CONNECTION: 1575 if (!hci_can_send_command_packet_now()) break; 1576 // send connection request - set state first 1577 channel->state = L2CAP_STATE_WAIT_CONNECTION_COMPLETE; 1578 // BD_ADDR, Packet_Type, Page_Scan_Repetition_Mode, Reserved, Clock_Offset, Allow_Role_Switch 1579 (void)memcpy(l2cap_outgoing_classic_addr, channel->address, 6); 1580 hci_send_cmd(&hci_create_connection, channel->address, hci_usable_acl_packet_types(), 0, 0, 0, hci_get_allow_role_switch()); 1581 break; 1582 1583 case L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_DECLINE: 1584 if (!hci_can_send_acl_packet_now(channel->con_handle)) return false; 1585 channel->state = L2CAP_STATE_INVALID; 1586 l2cap_send_classic_signaling_packet(channel->con_handle, CONNECTION_RESPONSE, channel->remote_sig_id, 1587 channel->local_cid, channel->remote_cid, channel->reason, 0); 1588 // discard channel - l2cap_finialize_channel_close without sending l2cap close event 1589 btstack_linked_list_remove(&l2cap_channels, (btstack_linked_item_t *) channel); 1590 l2cap_free_channel_entry(channel); 1591 channel = NULL; 1592 break; 1593 1594 case L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_ACCEPT: 1595 if (!hci_can_send_acl_packet_now(channel->con_handle)) return false; 1596 channel->state = L2CAP_STATE_CONFIG; 1597 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ); 1598 l2cap_send_classic_signaling_packet(channel->con_handle, CONNECTION_RESPONSE, channel->remote_sig_id, 1599 channel->local_cid, channel->remote_cid, 0, 0); 1600 break; 1601 1602 case L2CAP_STATE_WILL_SEND_CONNECTION_REQUEST: 1603 if (!hci_can_send_acl_packet_now(channel->con_handle)) return false; 1604 // success, start l2cap handshake 1605 channel->local_sig_id = l2cap_next_sig_id(); 1606 channel->state = L2CAP_STATE_WAIT_CONNECT_RSP; 1607 l2cap_send_classic_signaling_packet(channel->con_handle, CONNECTION_REQUEST, channel->local_sig_id, 1608 channel->psm, channel->local_cid); 1609 l2cap_start_rtx(channel); 1610 break; 1611 1612 case L2CAP_STATE_CONFIG: 1613 if (!hci_can_send_acl_packet_now(channel->con_handle)) return false; 1614 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 1615 // fallback to basic mode if ERTM requested but not not supported by remote 1616 if (channel->mode == L2CAP_CHANNEL_MODE_ENHANCED_RETRANSMISSION){ 1617 if (!l2cap_ertm_mode(channel)){ 1618 l2cap_emit_simple_event_with_cid(channel, L2CAP_EVENT_ERTM_BUFFER_RELEASED); 1619 channel->mode = L2CAP_CHANNEL_MODE_BASIC; 1620 } 1621 } 1622 #endif 1623 if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP){ 1624 uint16_t flags = 0; 1625 channelStateVarClearFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP); 1626 if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_CONT) { 1627 flags = 1; 1628 } else { 1629 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SENT_CONF_RSP); 1630 } 1631 if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_INVALID){ 1632 channelStateVarClearFlag(channel, L2CAP_CHANNEL_STATE_VAR_SENT_CONF_RSP); 1633 l2cap_send_classic_signaling_packet(channel->con_handle, CONFIGURE_RESPONSE, channel->remote_sig_id, 1634 channel->remote_cid, flags, L2CAP_CONF_RESULT_UNKNOWN_OPTIONS, 1635 1, &channel->unknown_option); 1636 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 1637 } else if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_REJECTED){ 1638 channelStateVarClearFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_REJECTED); 1639 channelStateVarClearFlag(channel, L2CAP_CHANNEL_STATE_VAR_SENT_CONF_RSP); 1640 uint16_t options_size = l2cap_setup_options_ertm_response(channel, config_options); 1641 l2cap_send_classic_signaling_packet(channel->con_handle, CONFIGURE_RESPONSE, channel->remote_sig_id, 1642 channel->remote_cid, flags, 1643 L2CAP_CONF_RESULT_UNACCEPTABLE_PARAMETERS, options_size, 1644 &config_options); 1645 } else if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_ERTM){ 1646 channelStateVarClearFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_ERTM); 1647 channelStateVarClearFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_MTU); 1648 uint16_t options_size = l2cap_setup_options_ertm_response(channel, config_options); 1649 l2cap_send_classic_signaling_packet(channel->con_handle, CONFIGURE_RESPONSE, channel->remote_sig_id, 1650 channel->remote_cid, flags, L2CAP_CONF_RESULT_SUCCESS, 1651 options_size, &config_options); 1652 #endif 1653 } else if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_MTU){ 1654 channelStateVarClearFlag(channel,L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_MTU); 1655 uint16_t options_size = l2cap_setup_options_mtu_response(channel, config_options); 1656 l2cap_send_classic_signaling_packet(channel->con_handle, CONFIGURE_RESPONSE, channel->remote_sig_id, 1657 channel->remote_cid, flags, L2CAP_CONF_RESULT_SUCCESS, 1658 options_size, &config_options); 1659 } else { 1660 l2cap_send_classic_signaling_packet(channel->con_handle, CONFIGURE_RESPONSE, channel->remote_sig_id, 1661 channel->remote_cid, flags, L2CAP_CONF_RESULT_SUCCESS, 0, NULL); 1662 } 1663 channelStateVarClearFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_CONT); 1664 } 1665 else if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ){ 1666 channelStateVarClearFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ); 1667 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SENT_CONF_REQ); 1668 channel->local_sig_id = l2cap_next_sig_id(); 1669 uint16_t options_size = l2cap_setup_options_request(channel, config_options); 1670 l2cap_send_classic_signaling_packet(channel->con_handle, CONFIGURE_REQUEST, channel->local_sig_id, 1671 channel->remote_cid, 0, options_size, &config_options); 1672 l2cap_start_rtx(channel); 1673 } 1674 if (l2cap_channel_ready_for_open(channel)){ 1675 channel->state = L2CAP_STATE_OPEN; 1676 l2cap_emit_channel_opened(channel, 0); // success 1677 } 1678 break; 1679 1680 case L2CAP_STATE_WILL_SEND_DISCONNECT_RESPONSE: 1681 if (!hci_can_send_acl_packet_now(channel->con_handle)) return false; 1682 channel->state = L2CAP_STATE_INVALID; 1683 l2cap_send_classic_signaling_packet(channel->con_handle, DISCONNECTION_RESPONSE, channel->remote_sig_id, 1684 channel->local_cid, channel->remote_cid); 1685 // we don't start an RTX timer for a disconnect - there's no point in closing the channel if the other side doesn't respond :) 1686 l2cap_finalize_channel_close(channel); // -- remove from list 1687 channel = NULL; 1688 break; 1689 1690 case L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST: 1691 if (!hci_can_send_acl_packet_now(channel->con_handle)) return false; 1692 channel->local_sig_id = l2cap_next_sig_id(); 1693 channel->state = L2CAP_STATE_WAIT_DISCONNECT; 1694 l2cap_send_classic_signaling_packet(channel->con_handle, DISCONNECTION_REQUEST, channel->local_sig_id, 1695 channel->remote_cid, channel->local_cid); 1696 break; 1697 default: 1698 break; 1699 } 1700 1701 // handle channel finalize on L2CAP_STATE_WILL_SEND_DISCONNECT_RESPONSE and L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_DECLINE 1702 return channel == NULL; 1703 } 1704 1705 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 1706 static void l2cap_run_for_classic_channel_ertm(l2cap_channel_t * channel){ 1707 1708 // ERTM mode 1709 if (channel->mode != L2CAP_CHANNEL_MODE_ENHANCED_RETRANSMISSION) return; 1710 1711 // check if we can still send 1712 if (channel->con_handle == HCI_CON_HANDLE_INVALID) return; 1713 if (!hci_can_send_acl_packet_now(channel->con_handle)) return; 1714 1715 if (channel->send_supervisor_frame_receiver_ready){ 1716 channel->send_supervisor_frame_receiver_ready = 0; 1717 log_info("Send S-Frame: RR %u, final %u", channel->req_seq, channel->set_final_bit_after_packet_with_poll_bit_set); 1718 uint16_t control = l2cap_encanced_control_field_for_supevisor_frame( L2CAP_SUPERVISORY_FUNCTION_RR_RECEIVER_READY, 0, channel->set_final_bit_after_packet_with_poll_bit_set, channel->req_seq); 1719 channel->set_final_bit_after_packet_with_poll_bit_set = 0; 1720 l2cap_ertm_send_supervisor_frame(channel, control); 1721 return; 1722 } 1723 if (channel->send_supervisor_frame_receiver_ready_poll){ 1724 channel->send_supervisor_frame_receiver_ready_poll = 0; 1725 log_info("Send S-Frame: RR %u with poll=1 ", channel->req_seq); 1726 uint16_t control = l2cap_encanced_control_field_for_supevisor_frame( L2CAP_SUPERVISORY_FUNCTION_RR_RECEIVER_READY, 1, 0, channel->req_seq); 1727 l2cap_ertm_send_supervisor_frame(channel, control); 1728 return; 1729 } 1730 if (channel->send_supervisor_frame_receiver_not_ready){ 1731 channel->send_supervisor_frame_receiver_not_ready = 0; 1732 log_info("Send S-Frame: RNR %u", channel->req_seq); 1733 uint16_t control = l2cap_encanced_control_field_for_supevisor_frame( L2CAP_SUPERVISORY_FUNCTION_RNR_RECEIVER_NOT_READY, 0, 0, channel->req_seq); 1734 l2cap_ertm_send_supervisor_frame(channel, control); 1735 return; 1736 } 1737 if (channel->send_supervisor_frame_reject){ 1738 channel->send_supervisor_frame_reject = 0; 1739 log_info("Send S-Frame: REJ %u", channel->req_seq); 1740 uint16_t control = l2cap_encanced_control_field_for_supevisor_frame( L2CAP_SUPERVISORY_FUNCTION_REJ_REJECT, 0, 0, channel->req_seq); 1741 l2cap_ertm_send_supervisor_frame(channel, control); 1742 return; 1743 } 1744 if (channel->send_supervisor_frame_selective_reject){ 1745 channel->send_supervisor_frame_selective_reject = 0; 1746 log_info("Send S-Frame: SREJ %u", channel->expected_tx_seq); 1747 uint16_t control = l2cap_encanced_control_field_for_supevisor_frame( L2CAP_SUPERVISORY_FUNCTION_SREJ_SELECTIVE_REJECT, 0, channel->set_final_bit_after_packet_with_poll_bit_set, channel->expected_tx_seq); 1748 channel->set_final_bit_after_packet_with_poll_bit_set = 0; 1749 l2cap_ertm_send_supervisor_frame(channel, control); 1750 return; 1751 } 1752 1753 if (channel->srej_active){ 1754 int i; 1755 for (i=0;i<channel->num_tx_buffers;i++){ 1756 l2cap_ertm_tx_packet_state_t * tx_state = &channel->tx_packets_state[i]; 1757 if (tx_state->retransmission_requested) { 1758 tx_state->retransmission_requested = 0; 1759 uint8_t final = channel->set_final_bit_after_packet_with_poll_bit_set; 1760 channel->set_final_bit_after_packet_with_poll_bit_set = 0; 1761 l2cap_ertm_send_information_frame(channel, i, final); 1762 break; 1763 } 1764 } 1765 if (i == channel->num_tx_buffers){ 1766 // no retransmission request found 1767 channel->srej_active = 0; 1768 } else { 1769 // packet was sent 1770 return; 1771 } 1772 } 1773 } 1774 #endif /* ERTM */ 1775 #endif /* Classic */ 1776 1777 static void l2cap_run_signaling_response(void) { 1778 1779 // check pending signaling responses 1780 while (l2cap_signaling_responses_pending){ 1781 1782 hci_con_handle_t handle = l2cap_signaling_responses[0].handle; 1783 1784 if (!hci_can_send_acl_packet_now(handle)) break; 1785 1786 uint8_t sig_id = l2cap_signaling_responses[0].sig_id; 1787 uint8_t response_code = l2cap_signaling_responses[0].code; 1788 uint16_t result = l2cap_signaling_responses[0].data; // CONNECTION_REQUEST, COMMAND_REJECT, REJECT_SM_PAIRING, L2CAP_CREDIT_BASED_CONNECTION_REQUEST 1789 uint8_t buffer[2]; // REJECT_SM_PAIRING 1790 uint16_t source_cid = l2cap_signaling_responses[0].cid; // CONNECTION_REQUEST, REJECT_SM_PAIRING 1791 #ifdef ENABLE_CLASSIC 1792 uint16_t info_type = l2cap_signaling_responses[0].data; // INFORMATION_REQUEST 1793 #endif 1794 #ifdef ENABLE_L2CAP_ENHANCED_CREDIT_BASED_FLOW_CONTROL_MODE 1795 uint8_t num_channels = l2cap_signaling_responses[0].cid >> 8; // L2CAP_CREDIT_BASED_CONNECTION_REQUEST 1796 uint16_t signaling_cid = (uint16_t) l2cap_signaling_responses[0].cid & 0xff; // L2CAP_CREDIT_BASED_CONNECTION_REQUEST, L2CAP_CREDIT_BASED_CONNECTION_REQUEST 1797 #endif 1798 1799 // remove first item before sending (to avoid sending response mutliple times) 1800 l2cap_signaling_responses_pending--; 1801 int i; 1802 for (i=0; i < l2cap_signaling_responses_pending; i++){ 1803 (void)memcpy(&l2cap_signaling_responses[i], 1804 &l2cap_signaling_responses[i + 1], 1805 sizeof(l2cap_signaling_response_t)); 1806 } 1807 1808 switch (response_code){ 1809 #ifdef ENABLE_CLASSIC 1810 case CONNECTION_REQUEST: 1811 l2cap_send_classic_signaling_packet(handle, CONNECTION_RESPONSE, sig_id, source_cid, 0, result, 0); 1812 break; 1813 case ECHO_REQUEST: 1814 l2cap_send_classic_signaling_packet(handle, ECHO_RESPONSE, sig_id, 0, NULL); 1815 break; 1816 case INFORMATION_REQUEST: 1817 switch (info_type){ 1818 case L2CAP_INFO_TYPE_CONNECTIONLESS_MTU: { 1819 uint16_t connectionless_mtu = hci_max_acl_data_packet_length(); 1820 l2cap_send_classic_signaling_packet(handle, INFORMATION_RESPONSE, sig_id, info_type, 0, 1821 sizeof(connectionless_mtu), &connectionless_mtu); 1822 } 1823 break; 1824 case L2CAP_INFO_TYPE_EXTENDED_FEATURES_SUPPORTED: { 1825 uint32_t features = l2cap_extended_features_mask(); 1826 l2cap_send_classic_signaling_packet(handle, INFORMATION_RESPONSE, sig_id, info_type, 0, 1827 sizeof(features), &features); 1828 } 1829 break; 1830 case L2CAP_INFO_TYPE_FIXED_CHANNELS_SUPPORTED: { 1831 uint8_t map[8]; 1832 memset(map, 0, 8); 1833 // L2CAP Signaling Channel (bit 1) + Connectionless reception (bit 2) 1834 map[0] = (1 << 1) | (1 << 2); 1835 #if defined(ENABLE_BLE) || defined (ENABLE_EXPLICIT_BR_EDR_SECURITY_MANAGER) 1836 // BR/EDR Security Manager (bit 7) 1837 map[0] |= (1 << 7); 1838 #endif 1839 l2cap_send_classic_signaling_packet(handle, INFORMATION_RESPONSE, sig_id, info_type, 0, 1840 sizeof(map), &map); 1841 } 1842 break; 1843 default: 1844 // all other types are not supported 1845 l2cap_send_classic_signaling_packet(handle, INFORMATION_RESPONSE, sig_id, info_type, 1, 0, NULL); 1846 break; 1847 } 1848 break; 1849 case COMMAND_REJECT: 1850 l2cap_send_classic_signaling_packet(handle, COMMAND_REJECT, sig_id, result, 0, NULL); 1851 break; 1852 #endif 1853 #ifdef ENABLE_BLE 1854 case LE_CREDIT_BASED_CONNECTION_REQUEST: 1855 l2cap_send_le_signaling_packet(handle, LE_CREDIT_BASED_CONNECTION_RESPONSE, sig_id, 0, 0, 0, 0, result); 1856 break; 1857 case COMMAND_REJECT_LE: 1858 l2cap_send_le_signaling_packet(handle, COMMAND_REJECT, sig_id, result, 0, NULL); 1859 break; 1860 #endif 1861 #ifdef ENABLE_L2CAP_ENHANCED_CREDIT_BASED_FLOW_CONTROL_MODE 1862 case L2CAP_CREDIT_BASED_CONNECTION_REQUEST: { 1863 // send variable size array or cids with each cid being zero 1864 uint16_t cids[6]; 1865 (void) memset(cids, 0xff, sizeof(cids)); 1866 (void) memset(cids, 0x00, num_channels * sizeof(uint16_t)); 1867 l2cap_send_general_signaling_packet(handle, signaling_cid, L2CAP_CREDIT_BASED_CONNECTION_RESPONSE, 1868 sig_id, 0, 0, 0, result, cids); 1869 break; 1870 } 1871 1872 case L2CAP_CREDIT_BASED_RECONFIGURE_REQUEST: 1873 l2cap_send_general_signaling_packet(handle, signaling_cid, L2CAP_CREDIT_BASED_RECONFIGURE_RESPONSE, 1874 sig_id, result); 1875 break; 1876 #endif 1877 case SM_PAIRING_FAILED: 1878 buffer[0] = SM_CODE_PAIRING_FAILED; 1879 buffer[1] = result; 1880 l2cap_send_connectionless(handle, source_cid, buffer, 2); 1881 break; 1882 default: 1883 // should not happen 1884 break; 1885 } 1886 } 1887 } 1888 1889 #ifdef ENABLE_CLASSIC 1890 static bool l2ap_run_information_requests(void){ 1891 // send l2cap information request if requested 1892 btstack_linked_list_iterator_t it; 1893 hci_connections_get_iterator(&it); 1894 uint8_t info_type; 1895 l2cap_information_state_t new_state; 1896 while(btstack_linked_list_iterator_has_next(&it)){ 1897 hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it); 1898 switch (connection->l2cap_state.information_state){ 1899 case L2CAP_INFORMATION_STATE_W2_SEND_EXTENDED_FEATURE_REQUEST: 1900 info_type = L2CAP_INFO_TYPE_EXTENDED_FEATURES_SUPPORTED; 1901 new_state = L2CAP_INFORMATION_STATE_W4_EXTENDED_FEATURE_RESPONSE; 1902 break; 1903 case L2CAP_INFORMATION_STATE_W2_SEND_FIXED_CHANNELS_REQUEST: 1904 info_type = L2CAP_INFO_TYPE_FIXED_CHANNELS_SUPPORTED; 1905 new_state = L2CAP_INFORMATION_STATE_W4_FIXED_CHANNELS_RESPONSE; 1906 break; 1907 default: 1908 continue; 1909 } 1910 if (!hci_can_send_acl_packet_now(connection->con_handle)) break; 1911 1912 connection->l2cap_state.information_state = new_state; 1913 uint8_t sig_id = l2cap_next_sig_id(); 1914 l2cap_send_classic_signaling_packet(connection->con_handle, INFORMATION_REQUEST, sig_id, info_type); 1915 } 1916 return false; 1917 } 1918 #endif 1919 1920 #ifdef ENABLE_L2CAP_LE_CREDIT_BASED_FLOW_CONTROL_MODE 1921 static void l2cap_cbm_run_channels(void){ 1922 btstack_linked_list_iterator_t it; 1923 btstack_linked_list_iterator_init(&it, &l2cap_channels); 1924 while (btstack_linked_list_iterator_has_next(&it)){ 1925 uint16_t mps; 1926 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 1927 1928 if (channel->channel_type != L2CAP_CHANNEL_TYPE_CHANNEL_CBM) continue; 1929 1930 // log_info("l2cap_run: channel %p, state %u, var 0x%02x", channel, channel->state, channel->state_var); 1931 switch (channel->state){ 1932 case L2CAP_STATE_WILL_SEND_LE_CONNECTION_REQUEST: 1933 if (!hci_can_send_acl_packet_now(channel->con_handle)) break; 1934 channel->state = L2CAP_STATE_WAIT_LE_CONNECTION_RESPONSE; 1935 // le psm, source cid, mtu, mps, initial credits 1936 channel->local_sig_id = l2cap_next_sig_id(); 1937 channel->credits_incoming = channel->new_credits_incoming; 1938 channel->new_credits_incoming = 0; 1939 mps = btstack_min(l2cap_max_le_mtu(), channel->local_mtu); 1940 l2cap_send_le_signaling_packet( channel->con_handle, LE_CREDIT_BASED_CONNECTION_REQUEST, channel->local_sig_id, channel->psm, channel->local_cid, channel->local_mtu, mps, channel->credits_incoming); 1941 break; 1942 case L2CAP_STATE_WILL_SEND_LE_CONNECTION_RESPONSE_ACCEPT: 1943 if (!hci_can_send_acl_packet_now(channel->con_handle)) break; 1944 // TODO: support larger MPS 1945 channel->state = L2CAP_STATE_OPEN; 1946 channel->credits_incoming = channel->new_credits_incoming; 1947 channel->new_credits_incoming = 0; 1948 mps = btstack_min(l2cap_max_le_mtu(), channel->local_mtu); 1949 l2cap_send_le_signaling_packet(channel->con_handle, LE_CREDIT_BASED_CONNECTION_RESPONSE, channel->remote_sig_id, channel->local_cid, channel->local_mtu, mps, channel->credits_incoming, 0); 1950 // notify client 1951 l2cap_cbm_emit_channel_opened(channel, ERROR_CODE_SUCCESS); 1952 break; 1953 case L2CAP_STATE_WILL_SEND_LE_CONNECTION_RESPONSE_DECLINE: 1954 if (!hci_can_send_acl_packet_now(channel->con_handle)) break; 1955 channel->state = L2CAP_STATE_INVALID; 1956 l2cap_send_le_signaling_packet(channel->con_handle, LE_CREDIT_BASED_CONNECTION_RESPONSE, channel->remote_sig_id, 0, 0, 0, 0, channel->reason); 1957 // discard channel - l2cap_finialize_channel_close without sending l2cap close event 1958 btstack_linked_list_iterator_remove(&it); 1959 l2cap_free_channel_entry(channel); 1960 break; 1961 case L2CAP_STATE_OPEN: 1962 if (!hci_can_send_acl_packet_now(channel->con_handle)) break; 1963 if (channel->new_credits_incoming){ 1964 l2cap_credit_based_send_credits(channel); 1965 } 1966 break; 1967 case L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST: 1968 if (!hci_can_send_acl_packet_now(channel->con_handle)) break; 1969 channel->local_sig_id = l2cap_next_sig_id(); 1970 channel->state = L2CAP_STATE_WAIT_DISCONNECT; 1971 l2cap_send_le_signaling_packet( channel->con_handle, DISCONNECTION_REQUEST, channel->local_sig_id, channel->remote_cid, channel->local_cid); 1972 break; 1973 case L2CAP_STATE_WILL_SEND_DISCONNECT_RESPONSE: 1974 if (!hci_can_send_acl_packet_now(channel->con_handle)) break; 1975 channel->state = L2CAP_STATE_INVALID; 1976 l2cap_send_le_signaling_packet( channel->con_handle, DISCONNECTION_RESPONSE, channel->remote_sig_id, channel->local_cid, channel->remote_cid); 1977 l2cap_cbm_finialize_channel_close(channel); // -- remove from list 1978 break; 1979 default: 1980 break; 1981 } 1982 } 1983 } 1984 1985 static inline uint8_t l2cap_cbm_status_for_result(uint16_t result) { 1986 switch (result) { 1987 case L2CAP_CBM_CONNECTION_RESULT_SUCCESS: 1988 return ERROR_CODE_SUCCESS; 1989 case L2CAP_CBM_CONNECTION_RESULT_SPSM_NOT_SUPPORTED: 1990 return L2CAP_CONNECTION_RESPONSE_RESULT_REFUSED_PSM; 1991 case L2CAP_CBM_CONNECTION_RESULT_NO_RESOURCES_AVAILABLE: 1992 return L2CAP_CONNECTION_RESPONSE_RESULT_REFUSED_RESOURCES; 1993 case L2CAP_CBM_CONNECTION_RESULT_INSUFFICIENT_AUTHENTICATION: 1994 case L2CAP_CBM_CONNECTION_RESULT_INSUFFICIENT_AUTHORIZATION: 1995 case L2CAP_CBM_CONNECTION_RESULT_ENCYRPTION_KEY_SIZE_TOO_SHORT: 1996 case L2CAP_CBM_CONNECTION_RESULT_INSUFFICIENT_ENCRYPTION: 1997 return L2CAP_CONNECTION_RESPONSE_RESULT_REFUSED_SECURITY; 1998 default: 1999 // invalid Source CID, Source CID already allocated, unacceptable parameters 2000 return L2CAP_CONNECTION_RESPONSE_UNKNOWN_ERROR; 2001 } 2002 } 2003 2004 #endif 2005 2006 #ifdef ENABLE_L2CAP_ENHANCED_CREDIT_BASED_FLOW_CONTROL_MODE 2007 2008 // 11BH22222 2009 static void l2cap_ecbm_emit_channel_opened(l2cap_channel_t *channel, uint8_t status) { 2010 log_info("opened ecbm channel status 0x%x addr_type %u addr %s handle 0x%x psm 0x%x local_cid 0x%x remote_cid 0x%x local_mtu %u, remote_mtu %u", 2011 status, channel->address_type, bd_addr_to_str(channel->address), channel->con_handle, channel->psm, 2012 channel->local_cid, channel->remote_cid, channel->local_mtu, channel->remote_mtu); 2013 uint8_t event[23]; 2014 event[0] = L2CAP_EVENT_ECBM_CHANNEL_OPENED; 2015 event[1] = sizeof(event) - 2u; 2016 event[2] = status; 2017 event[3] = channel->address_type; 2018 reverse_bd_addr(channel->address, &event[4]); 2019 little_endian_store_16(event, 10, channel->con_handle); 2020 event[12] = (channel->state_var & L2CAP_CHANNEL_STATE_VAR_INCOMING) ? 1 : 0; 2021 little_endian_store_16(event, 13, channel->psm); 2022 little_endian_store_16(event, 15, channel->local_cid); 2023 little_endian_store_16(event, 17, channel->remote_cid); 2024 little_endian_store_16(event, 19, channel->local_mtu); 2025 little_endian_store_16(event, 21, channel->remote_mtu); 2026 hci_dump_packet(HCI_EVENT_PACKET, 0, event, sizeof(event)); 2027 l2cap_dispatch_to_channel(channel, HCI_EVENT_PACKET, event, sizeof(event)); 2028 } 2029 2030 static void l2cap_ecbm_emit_reconfigure_complete(l2cap_channel_t *channel, uint16_t result) { 2031 // emit event 2032 uint8_t event[6]; 2033 event[0] = L2CAP_EVENT_ECBM_RECONFIGURATION_COMPLETE; 2034 event[1] = sizeof(event) - 2; 2035 little_endian_store_16(event, 2, channel->local_cid); 2036 little_endian_store_16(event, 4, result); 2037 l2cap_dispatch_to_channel(channel, HCI_EVENT_PACKET, event, sizeof(event)); 2038 } 2039 2040 static void l2cap_ecbm_run_channels(void) { 2041 hci_con_handle_t con_handle = HCI_CON_HANDLE_INVALID; 2042 // num max channels + 1 for signaling pdu generator 2043 uint16_t cids[L2CAP_ECBM_MAX_CID_ARRAY_SIZE + 1]; 2044 uint8_t num_cids = 0; 2045 uint8_t sig_id; 2046 uint16_t spsm; 2047 L2CAP_STATE matching_state; 2048 bool match_remote_sig_cid; 2049 uint8_t result = 0; 2050 uint16_t local_mtu; 2051 uint16_t initial_credits; 2052 uint16_t signaling_cid; 2053 L2CAP_STATE new_state; 2054 2055 // pick first channel that needs to send a combined signaling pdu and setup collection via break 2056 // then collect all others that belong to the same pdu 2057 btstack_linked_list_iterator_t it; 2058 btstack_linked_list_iterator_init(&it, &l2cap_channels); 2059 while (btstack_linked_list_iterator_has_next(&it)) { 2060 l2cap_channel_t *channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 2061 if (channel->channel_type != L2CAP_CHANNEL_TYPE_CHANNEL_ECBM) continue; 2062 if (con_handle == HCI_CON_HANDLE_INVALID) { 2063 switch (channel->state) { 2064 case L2CAP_STATE_WILL_SEND_ENHANCED_CONNECTION_REQUEST: 2065 if (!hci_can_send_acl_packet_now(channel->con_handle)) continue; 2066 local_mtu = channel->local_mtu; 2067 spsm = channel->psm; 2068 result = channel->reason; 2069 initial_credits = channel->credits_incoming; 2070 sig_id = channel->local_sig_id; 2071 new_state = L2CAP_STATE_WAIT_ENHANCED_CONNECTION_RESPONSE; 2072 match_remote_sig_cid = false; 2073 break; 2074 case L2CAP_STATE_WILL_SEND_ENHANCED_CONNECTION_RESPONSE: 2075 if (!hci_can_send_acl_packet_now(channel->con_handle)) continue; 2076 local_mtu = channel->local_mtu; 2077 initial_credits = channel->credits_incoming; 2078 sig_id = channel->remote_sig_id; 2079 new_state = L2CAP_STATE_OPEN; 2080 match_remote_sig_cid = true; 2081 break; 2082 case L2CAP_STATE_WILL_SEND_EHNANCED_RENEGOTIATION_REQUEST: 2083 if (!hci_can_send_acl_packet_now(channel->con_handle)) continue; 2084 sig_id = channel->local_sig_id; 2085 local_mtu = channel->renegotiate_mtu; 2086 new_state = L2CAP_STATE_WAIT_ENHANCED_RENEGOTIATION_RESPONSE; 2087 match_remote_sig_cid = false; 2088 break; 2089 case L2CAP_STATE_OPEN: 2090 if (!hci_can_send_acl_packet_now(channel->con_handle)) continue; 2091 if (channel->new_credits_incoming) { 2092 l2cap_credit_based_send_credits(channel); 2093 } 2094 continue; 2095 case L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST: 2096 if (!hci_can_send_acl_packet_now(channel->con_handle)) continue; 2097 channel->local_sig_id = l2cap_next_sig_id(); 2098 channel->state = L2CAP_STATE_WAIT_DISCONNECT; 2099 signaling_cid = channel->address_type == BD_ADDR_TYPE_ACL ? L2CAP_CID_SIGNALING : L2CAP_CID_SIGNALING_LE; 2100 l2cap_send_general_signaling_packet(channel->con_handle, signaling_cid, DISCONNECTION_REQUEST, 2101 channel->local_sig_id, channel->remote_cid, channel->local_cid); 2102 continue; 2103 case L2CAP_STATE_WILL_SEND_DISCONNECT_RESPONSE: 2104 if (!hci_can_send_acl_packet_now(channel->con_handle)) continue; 2105 channel->state = L2CAP_STATE_INVALID; 2106 signaling_cid = channel->address_type == BD_ADDR_TYPE_ACL ? L2CAP_CID_SIGNALING : L2CAP_CID_SIGNALING_LE; 2107 l2cap_send_general_signaling_packet(channel->con_handle, signaling_cid, DISCONNECTION_RESPONSE, 2108 channel->remote_sig_id, channel->local_cid, 2109 channel->remote_cid); 2110 l2cap_cbm_finialize_channel_close(channel); // -- remove from list 2111 continue; 2112 default: 2113 continue; 2114 } 2115 2116 // channel picked - setup cid array and collect info 2117 (void) memset(cids, 0xff, sizeof(cids)); 2118 (void) memset(cids, 0, channel->num_cids * sizeof(uint16_t)); 2119 matching_state = channel->state; 2120 con_handle = channel->con_handle; 2121 signaling_cid = channel->address_type == BD_ADDR_TYPE_ACL ? L2CAP_CID_SIGNALING : L2CAP_CID_SIGNALING_LE; 2122 num_cids = channel->num_cids; 2123 2124 } else { 2125 // check if it matches first channel by state, con_handle, and signaling id 2126 if (matching_state != channel->state) continue; 2127 if (channel->con_handle != con_handle) continue; 2128 if (match_remote_sig_cid) { 2129 if (channel->remote_sig_id != sig_id) continue; 2130 } else { 2131 if (channel->local_sig_id != sig_id) continue; 2132 } 2133 } 2134 2135 // add this cid 2136 cids[channel->cid_index] = channel->local_cid; 2137 2138 // set new state 2139 channel->state = new_state; 2140 2141 // handle open for L2CAP_STATE_WILL_SEND_ENHANCED_CONNECTION_RESPONSE 2142 if (matching_state == L2CAP_STATE_WILL_SEND_ENHANCED_CONNECTION_RESPONSE) { 2143 if (channel->reason == L2CAP_ECBM_CONNECTION_RESULT_ALL_SUCCESS) { 2144 l2cap_ecbm_emit_channel_opened(channel, ERROR_CODE_SUCCESS); 2145 } else { 2146 result = channel->reason; 2147 btstack_linked_list_iterator_remove(&it); 2148 btstack_memory_l2cap_channel_free(channel); 2149 } 2150 } 2151 } 2152 2153 if (con_handle != HCI_CON_HANDLE_INVALID) { 2154 // TODO: get MTU for both BR/EDR and LE 2155 uint16_t mps = btstack_min(l2cap_enhanced_mps_max, btstack_min(l2cap_max_le_mtu(), local_mtu)); 2156 switch (matching_state) { 2157 case L2CAP_STATE_WILL_SEND_ENHANCED_CONNECTION_REQUEST: 2158 log_info("send combined connection request for %u cids", num_cids); 2159 l2cap_send_general_signaling_packet(con_handle, signaling_cid, L2CAP_CREDIT_BASED_CONNECTION_REQUEST, 2160 sig_id, spsm, local_mtu, mps, initial_credits, cids); 2161 break; 2162 case L2CAP_STATE_WILL_SEND_ENHANCED_CONNECTION_RESPONSE: 2163 log_info("send combined connection response for %u cids", num_cids); 2164 l2cap_send_general_signaling_packet(con_handle, signaling_cid, L2CAP_CREDIT_BASED_CONNECTION_RESPONSE, 2165 sig_id, local_mtu, mps, initial_credits, result, cids); 2166 break; 2167 case L2CAP_STATE_WILL_SEND_EHNANCED_RENEGOTIATION_REQUEST: 2168 log_info("send combined renegotiation request for %u cids", num_cids); 2169 l2cap_send_general_signaling_packet(con_handle, signaling_cid, L2CAP_CREDIT_BASED_RECONFIGURE_REQUEST, 2170 sig_id, local_mtu, mps, cids); 2171 break; 2172 default: 2173 break; 2174 } 2175 } 2176 } 2177 #endif 2178 2179 // MARK: L2CAP_RUN 2180 // process outstanding signaling tasks 2181 static void l2cap_run(void){ 2182 2183 // log_info("l2cap_run: entered"); 2184 l2cap_run_signaling_response(); 2185 2186 #ifdef ENABLE_CLASSIC 2187 bool done = l2ap_run_information_requests(); 2188 if (done) return; 2189 #endif 2190 2191 #if defined(ENABLE_CLASSIC) || defined(ENABLE_BLE) 2192 btstack_linked_list_iterator_t it; 2193 #endif 2194 2195 #ifdef ENABLE_CLASSIC 2196 btstack_linked_list_iterator_init(&it, &l2cap_channels); 2197 while (btstack_linked_list_iterator_has_next(&it)){ 2198 2199 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 2200 2201 if (channel->channel_type != L2CAP_CHANNEL_TYPE_CLASSIC) continue; 2202 2203 // log_info("l2cap_run: channel %p, state %u, var 0x%02x", channel, channel->state, channel->state_var); 2204 bool finalized = l2cap_run_for_classic_channel(channel); 2205 2206 if (!finalized) { 2207 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 2208 l2cap_run_for_classic_channel_ertm(channel); 2209 #endif 2210 } 2211 } 2212 #endif 2213 2214 #ifdef ENABLE_L2CAP_LE_CREDIT_BASED_FLOW_CONTROL_MODE 2215 l2cap_cbm_run_channels(); 2216 #endif 2217 2218 #ifdef ENABLE_L2CAP_ENHANCED_CREDIT_BASED_FLOW_CONTROL_MODE 2219 l2cap_ecbm_run_channels(); 2220 #endif 2221 2222 #ifdef ENABLE_BLE 2223 // send l2cap con paramter update if necessary 2224 hci_connections_get_iterator(&it); 2225 while(btstack_linked_list_iterator_has_next(&it)){ 2226 hci_connection_t * connection = (hci_connection_t *) btstack_linked_list_iterator_next(&it); 2227 if ((connection->address_type != BD_ADDR_TYPE_LE_PUBLIC) && (connection->address_type != BD_ADDR_TYPE_LE_RANDOM)) continue; 2228 if (!hci_can_send_acl_packet_now(connection->con_handle)) continue; 2229 switch (connection->le_con_parameter_update_state){ 2230 case CON_PARAMETER_UPDATE_SEND_REQUEST: 2231 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE; 2232 l2cap_send_le_signaling_packet(connection->con_handle, CONNECTION_PARAMETER_UPDATE_REQUEST, l2cap_next_sig_id(), 2233 connection->le_conn_interval_min, connection->le_conn_interval_max, connection->le_conn_latency, connection->le_supervision_timeout); 2234 break; 2235 case CON_PARAMETER_UPDATE_SEND_RESPONSE: 2236 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_CHANGE_HCI_CON_PARAMETERS; 2237 l2cap_send_le_signaling_packet(connection->con_handle, CONNECTION_PARAMETER_UPDATE_RESPONSE, connection->le_con_param_update_identifier, 0); 2238 break; 2239 case CON_PARAMETER_UPDATE_DENY: 2240 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_NONE; 2241 l2cap_send_le_signaling_packet(connection->con_handle, CONNECTION_PARAMETER_UPDATE_RESPONSE, connection->le_con_param_update_identifier, 1); 2242 break; 2243 default: 2244 break; 2245 } 2246 } 2247 #endif 2248 2249 if (l2cap_call_notify_channel_in_run){ 2250 l2cap_call_notify_channel_in_run = false; 2251 l2cap_notify_channel_can_send(); 2252 } 2253 2254 // log_info("l2cap_run: exit"); 2255 } 2256 2257 #ifdef ENABLE_CLASSIC 2258 static void l2cap_ready_to_connect(l2cap_channel_t * channel){ 2259 2260 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 2261 // assumption: outgoing connection 2262 if (channel->mode == L2CAP_CHANNEL_MODE_ENHANCED_RETRANSMISSION){ 2263 // ERTM requested: trigger information request if not already started then wait for response 2264 hci_connection_t * connection = hci_connection_for_handle(channel->con_handle); 2265 switch (connection->l2cap_state.information_state){ 2266 case L2CAP_INFORMATION_STATE_DONE: 2267 break; 2268 case L2CAP_INFORMATION_STATE_IDLE: 2269 connection->l2cap_state.information_state = L2CAP_INFORMATION_STATE_W2_SEND_EXTENDED_FEATURE_REQUEST; 2270 /* fall through */ 2271 default: 2272 channel->state = L2CAP_STATE_WAIT_OUTGOING_EXTENDED_FEATURES; 2273 return; 2274 } 2275 } 2276 #endif 2277 2278 // fine, go ahead 2279 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_REQUEST; 2280 } 2281 2282 static void l2cap_handle_connection_complete(hci_con_handle_t con_handle, l2cap_channel_t * channel){ 2283 if ((channel->state == L2CAP_STATE_WAIT_CONNECTION_COMPLETE) || (channel->state == L2CAP_STATE_WILL_SEND_CREATE_CONNECTION)) { 2284 log_info("connection complete con_handle %04x - for channel %p cid 0x%04x", (int) con_handle, channel, channel->local_cid); 2285 channel->con_handle = con_handle; 2286 // query remote features if pairing is required 2287 if (channel->required_security_level > LEVEL_0){ 2288 channel->state = L2CAP_STATE_WAIT_REMOTE_SUPPORTED_FEATURES; 2289 hci_remote_features_query(con_handle); 2290 } else { 2291 l2cap_ready_to_connect(channel); 2292 } 2293 } 2294 } 2295 2296 static void l2cap_handle_remote_supported_features_received(l2cap_channel_t * channel){ 2297 if (channel->state != L2CAP_STATE_WAIT_REMOTE_SUPPORTED_FEATURES) return; 2298 // double check if all feature pages are complete 2299 2300 bool security_required = channel->required_security_level > LEVEL_0; 2301 2302 // abort if Secure Connections Only Mode with legacy connection 2303 if (security_required && gap_get_secure_connections_only_mode() && gap_secure_connection(channel->con_handle) == 0){ 2304 l2cap_handle_channel_open_failed(channel, L2CAP_CONNECTION_RESPONSE_RESULT_REFUSED_SECURITY); 2305 btstack_linked_list_remove(&l2cap_channels, (btstack_linked_item_t *) channel); 2306 l2cap_free_channel_entry(channel); 2307 return; 2308 } 2309 2310 if ((channel->state_var & L2CAP_CHANNEL_STATE_VAR_INCOMING) != 0){ 2311 2312 // Core V5.2, Vol 3, Part C, 5.2.2.2 - Security Mode 4 2313 // When a remote device attempts to access a service offered by a Bluetooth device that is in security mode 4 2314 // and a sufficient link key exists and authentication has not been performed the local device shall authenticate 2315 // the remote device and enable encryption after the channel establishment request is received but before a channel 2316 // establishment confirmation (L2CAP_ConnectRsp with result code of 0x0000 or a higher-level channel establishment 2317 // confirmation such as that of RFCOMM) is sent. 2318 2319 // If the remote device has indicated support for Secure Simple Pairing, a channel establishment request is 2320 // received for a service other than SDP, and encryption has not yet been enabled, then the local device shall 2321 // disconnect the ACL link with error code 0x05 - Authentication Failure. 2322 2323 // => Disconnect if l2cap request received in mode 4 and ssp supported, non-sdp psm, not encrypted, no link key available 2324 if ((gap_get_security_mode() == GAP_SECURITY_MODE_4) 2325 && gap_ssp_supported_on_both_sides(channel->con_handle) 2326 && (channel->psm != PSM_SDP) 2327 && (gap_encryption_key_size(channel->con_handle) == 0) 2328 && (gap_bonded(channel->con_handle) == false)){ 2329 hci_disconnect_security_block(channel->con_handle); 2330 return; 2331 } 2332 2333 // incoming: assert security requirements 2334 channel->state = L2CAP_STATE_WAIT_INCOMING_SECURITY_LEVEL_UPDATE; 2335 if (channel->required_security_level <= gap_security_level(channel->con_handle)){ 2336 l2cap_handle_security_level_incoming_sufficient(channel); 2337 } else { 2338 // send connection pending if not already done 2339 if ((channel->state_var & L2CAP_CHANNEL_STATE_VAR_SENT_CONN_RESP_PEND) == 0){ 2340 channel->state_var |= L2CAP_CHANNEL_STATE_VAR_SEND_CONN_RESP_PEND; 2341 } 2342 gap_request_security_level(channel->con_handle, channel->required_security_level); 2343 } 2344 } else { 2345 // outgoing: we have been waiting for remote supported features 2346 if (security_required){ 2347 // request security level 2348 channel->state = L2CAP_STATE_WAIT_OUTGOING_SECURITY_LEVEL_UPDATE; 2349 gap_request_security_level(channel->con_handle, channel->required_security_level); 2350 } else { 2351 l2cap_ready_to_connect(channel); 2352 } 2353 } 2354 } 2355 #endif 2356 2357 #ifdef L2CAP_USES_CHANNELS 2358 static l2cap_channel_t * l2cap_create_channel_entry(btstack_packet_handler_t packet_handler, l2cap_channel_type_t channel_type, bd_addr_t address, bd_addr_type_t address_type, 2359 uint16_t psm, uint16_t local_mtu, gap_security_level_t security_level){ 2360 2361 l2cap_channel_t * channel = btstack_memory_l2cap_channel_get(); 2362 if (!channel) { 2363 return NULL; 2364 } 2365 2366 // fill in 2367 channel->packet_handler = packet_handler; 2368 channel->channel_type = channel_type; 2369 bd_addr_copy(channel->address, address); 2370 channel->address_type = address_type; 2371 channel->psm = psm; 2372 channel->local_mtu = local_mtu; 2373 channel->remote_mtu = L2CAP_DEFAULT_MTU; 2374 channel->required_security_level = security_level; 2375 2376 // 2377 channel->local_cid = l2cap_next_local_cid(); 2378 channel->con_handle = HCI_CON_HANDLE_INVALID; 2379 2380 // set initial state 2381 channel->state = L2CAP_STATE_WILL_SEND_CREATE_CONNECTION; 2382 channel->state_var = L2CAP_CHANNEL_STATE_VAR_NONE; 2383 channel->remote_sig_id = L2CAP_SIG_ID_INVALID; 2384 channel->local_sig_id = L2CAP_SIG_ID_INVALID; 2385 2386 log_info("create channel %p, local_cid 0x%04x", channel, channel->local_cid); 2387 2388 return channel; 2389 } 2390 2391 static void l2cap_free_channel_entry(l2cap_channel_t * channel){ 2392 log_info("free channel %p, local_cid 0x%04x", channel, channel->local_cid); 2393 // assert all timers are stopped 2394 l2cap_stop_rtx(channel); 2395 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 2396 l2cap_ertm_stop_retransmission_timer(channel); 2397 l2cap_ertm_stop_monitor_timer(channel); 2398 #endif 2399 // free memory 2400 btstack_memory_l2cap_channel_free(channel); 2401 } 2402 #endif 2403 2404 #ifdef ENABLE_CLASSIC 2405 2406 /** 2407 * @brief Creates L2CAP channel to the PSM of a remote device with baseband address. A new baseband connection will be initiated if necessary. 2408 * @param packet_handler 2409 * @param address 2410 * @param psm 2411 * @param mtu 2412 * @param local_cid 2413 */ 2414 2415 uint8_t l2cap_create_channel(btstack_packet_handler_t channel_packet_handler, bd_addr_t address, uint16_t psm, uint16_t mtu, uint16_t * out_local_cid){ 2416 // limit MTU to the size of our outgoing HCI buffer 2417 uint16_t local_mtu = btstack_min(mtu, l2cap_max_mtu()); 2418 2419 // determine security level based on psm 2420 const gap_security_level_t security_level = l2cap_security_level_0_allowed_for_PSM(psm) ? LEVEL_0 : gap_get_security_level(); 2421 log_info("create channel addr %s psm 0x%x mtu %u -> local mtu %u, sec level %u", bd_addr_to_str(address), psm, mtu, local_mtu, (int) security_level); 2422 2423 l2cap_channel_t * channel = l2cap_create_channel_entry(channel_packet_handler, L2CAP_CHANNEL_TYPE_CLASSIC, address, BD_ADDR_TYPE_ACL, psm, local_mtu, security_level); 2424 if (!channel) { 2425 return BTSTACK_MEMORY_ALLOC_FAILED; 2426 } 2427 2428 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 2429 channel->mode = L2CAP_CHANNEL_MODE_BASIC; 2430 #endif 2431 2432 // add to connections list 2433 btstack_linked_list_add_tail(&l2cap_channels, (btstack_linked_item_t *) channel); 2434 2435 // store local_cid 2436 if (out_local_cid){ 2437 *out_local_cid = channel->local_cid; 2438 } 2439 2440 // state: L2CAP_STATE_WILL_SEND_CREATE_CONNECTION 2441 2442 // check if hci connection is already usable, 2443 hci_connection_t * conn = hci_connection_for_bd_addr_and_type(address, BD_ADDR_TYPE_ACL); 2444 if (conn && conn->state == OPEN){ 2445 // simulate connection complete 2446 l2cap_handle_connection_complete(conn->con_handle, channel); 2447 2448 // state: L2CAP_STATE_WAIT_REMOTE_SUPPORTED_FEATURES or L2CAP_STATE_WILL_SEND_CONNECTION_REQUEST 2449 2450 // simulate if remote supported features if requested and already received 2451 if ((channel->state == L2CAP_STATE_WAIT_REMOTE_SUPPORTED_FEATURES) && hci_remote_features_available(conn->con_handle)) { 2452 // simulate remote features received 2453 l2cap_handle_remote_supported_features_received(channel); 2454 } 2455 } 2456 2457 l2cap_run(); 2458 2459 return ERROR_CODE_SUCCESS; 2460 } 2461 2462 uint8_t l2cap_disconnect(uint16_t local_cid){ 2463 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 2464 if (!channel) { 2465 return L2CAP_LOCAL_CID_DOES_NOT_EXIST; 2466 } 2467 channel->state = L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST; 2468 l2cap_run(); 2469 return ERROR_CODE_SUCCESS; 2470 } 2471 2472 static void l2cap_handle_connection_failed_for_addr(bd_addr_t address, uint8_t status){ 2473 // mark all channels before emitting open events as these could trigger new connetion requests to the same device 2474 btstack_linked_list_iterator_t it; 2475 btstack_linked_list_iterator_init(&it, &l2cap_channels); 2476 while (btstack_linked_list_iterator_has_next(&it)){ 2477 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 2478 if (!l2cap_is_dynamic_channel_type(channel->channel_type)) continue; 2479 if (bd_addr_cmp( channel->address, address) != 0) continue; 2480 // channel for this address found 2481 switch (channel->state){ 2482 case L2CAP_STATE_WAIT_CONNECTION_COMPLETE: 2483 case L2CAP_STATE_WILL_SEND_CREATE_CONNECTION: 2484 channel->state = L2CAP_STATE_EMIT_OPEN_FAILED_AND_DISCARD; 2485 break; 2486 default: 2487 break; 2488 } 2489 } 2490 // emit and free marked entries. restart loop to deal with list changes 2491 int done = 0; 2492 while (!done) { 2493 done = 1; 2494 btstack_linked_list_iterator_init(&it, &l2cap_channels); 2495 while (btstack_linked_list_iterator_has_next(&it)){ 2496 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 2497 if (!l2cap_is_dynamic_channel_type(channel->channel_type)) continue; 2498 if (channel->state == L2CAP_STATE_EMIT_OPEN_FAILED_AND_DISCARD){ 2499 done = 0; 2500 // failure, forward error code 2501 l2cap_handle_channel_open_failed(channel, status); 2502 // discard channel 2503 btstack_linked_list_remove(&l2cap_channels, (btstack_linked_item_t *) channel); 2504 l2cap_free_channel_entry(channel); 2505 break; 2506 } 2507 } 2508 } 2509 2510 } 2511 2512 static void l2cap_handle_connection_success_for_addr(bd_addr_t address, hci_con_handle_t handle){ 2513 btstack_linked_list_iterator_t it; 2514 btstack_linked_list_iterator_init(&it, &l2cap_channels); 2515 while (btstack_linked_list_iterator_has_next(&it)){ 2516 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 2517 if (!l2cap_is_dynamic_channel_type(channel->channel_type)) continue; 2518 if ( ! bd_addr_cmp( channel->address, address) ){ 2519 l2cap_handle_connection_complete(handle, channel); 2520 } 2521 } 2522 // process 2523 l2cap_run(); 2524 } 2525 #endif 2526 2527 static bool l2cap_channel_ready_to_send(l2cap_channel_t * channel){ 2528 switch (channel->channel_type){ 2529 #ifdef ENABLE_CLASSIC 2530 case L2CAP_CHANNEL_TYPE_CLASSIC: 2531 if (channel->state != L2CAP_STATE_OPEN) return false; 2532 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 2533 // send if we have more data and remote windows isn't full yet 2534 if (channel->mode == L2CAP_CHANNEL_MODE_ENHANCED_RETRANSMISSION) { 2535 if (channel->unacked_frames >= btstack_min(channel->num_stored_tx_frames, channel->remote_tx_window_size)) return false; 2536 return hci_can_send_acl_classic_packet_now() != 0; 2537 } 2538 #endif 2539 if (!channel->waiting_for_can_send_now) return false; 2540 return (hci_can_send_acl_classic_packet_now() != 0); 2541 case L2CAP_CHANNEL_TYPE_CONNECTIONLESS: 2542 if (!channel->waiting_for_can_send_now) return false; 2543 return hci_can_send_acl_classic_packet_now() != 0; 2544 #endif 2545 #ifdef ENABLE_BLE 2546 case L2CAP_CHANNEL_TYPE_FIXED: 2547 if (!channel->waiting_for_can_send_now) return false; 2548 return hci_can_send_acl_le_packet_now() != 0; 2549 #ifdef ENABLE_L2CAP_LE_CREDIT_BASED_FLOW_CONTROL_MODE 2550 case L2CAP_CHANNEL_TYPE_CHANNEL_CBM: 2551 if (channel->state != L2CAP_STATE_OPEN) return false; 2552 if (channel->send_sdu_buffer == NULL) return false; 2553 if (channel->credits_outgoing == 0u) return false; 2554 return hci_can_send_acl_le_packet_now() != 0; 2555 #endif 2556 #endif 2557 #ifdef ENABLE_L2CAP_ENHANCED_CREDIT_BASED_FLOW_CONTROL_MODE 2558 case L2CAP_CHANNEL_TYPE_CHANNEL_ECBM: 2559 if (channel->state != L2CAP_STATE_OPEN) return false; 2560 if (channel->send_sdu_buffer == NULL) return false; 2561 if (channel->credits_outgoing == 0u) return false; 2562 if (channel->address_type == BD_ADDR_TYPE_ACL) { 2563 return hci_can_send_acl_classic_packet_now() != 0; 2564 } else { 2565 return hci_can_send_acl_le_packet_now() != 0; 2566 } 2567 #endif 2568 default: 2569 return false; 2570 } 2571 } 2572 2573 static void l2cap_channel_trigger_send(l2cap_channel_t * channel){ 2574 switch (channel->channel_type){ 2575 #ifdef ENABLE_CLASSIC 2576 case L2CAP_CHANNEL_TYPE_CLASSIC: 2577 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 2578 if (channel->mode == L2CAP_CHANNEL_MODE_ENHANCED_RETRANSMISSION) { 2579 l2cap_ertm_channel_send_information_frame(channel); 2580 return; 2581 } 2582 #endif 2583 channel->waiting_for_can_send_now = 0; 2584 l2cap_emit_can_send_now(channel->packet_handler, channel->local_cid); 2585 break; 2586 case L2CAP_CHANNEL_TYPE_CONNECTIONLESS: 2587 channel->waiting_for_can_send_now = 0; 2588 l2cap_emit_can_send_now(channel->packet_handler, channel->local_cid); 2589 break; 2590 #endif 2591 #ifdef ENABLE_BLE 2592 case L2CAP_CHANNEL_TYPE_FIXED: 2593 channel->waiting_for_can_send_now = 0; 2594 l2cap_emit_can_send_now(channel->packet_handler, channel->local_cid); 2595 break; 2596 #endif 2597 #ifdef ENABLE_L2CAP_LE_CREDIT_BASED_FLOW_CONTROL_MODE 2598 case L2CAP_CHANNEL_TYPE_CHANNEL_CBM: 2599 l2cap_credit_based_send_pdu(channel); 2600 break; 2601 #endif 2602 #ifdef ENABLE_L2CAP_ENHANCED_CREDIT_BASED_FLOW_CONTROL_MODE 2603 case L2CAP_CHANNEL_TYPE_CHANNEL_ECBM: 2604 l2cap_credit_based_send_pdu(channel); 2605 break; 2606 #endif 2607 default: 2608 break; 2609 } 2610 } 2611 2612 static void l2cap_notify_channel_can_send(void){ 2613 bool done = false; 2614 while (!done){ 2615 done = true; 2616 btstack_linked_list_iterator_t it; 2617 btstack_linked_list_iterator_init(&it, &l2cap_channels); 2618 while (btstack_linked_list_iterator_has_next(&it)){ 2619 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 2620 bool ready = l2cap_channel_ready_to_send(channel); 2621 if (!ready) continue; 2622 2623 // requeue channel for fairness 2624 btstack_linked_list_remove(&l2cap_channels, (btstack_linked_item_t *) channel); 2625 btstack_linked_list_add_tail(&l2cap_channels, (btstack_linked_item_t *) channel); 2626 2627 // trigger sending 2628 l2cap_channel_trigger_send(channel); 2629 2630 // exit inner loop as we just broke the iterator, but try again 2631 done = false; 2632 break; 2633 } 2634 } 2635 } 2636 2637 #ifdef L2CAP_USES_CHANNELS 2638 2639 static int l2cap_send_open_failed_on_hci_disconnect(l2cap_channel_t * channel){ 2640 // open cannot fail for for incoming connections 2641 if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_INCOMING) return 0; 2642 2643 // check state 2644 switch (channel->state){ 2645 case L2CAP_STATE_WILL_SEND_CREATE_CONNECTION: 2646 case L2CAP_STATE_WAIT_CONNECTION_COMPLETE: 2647 case L2CAP_STATE_WAIT_REMOTE_SUPPORTED_FEATURES: 2648 case L2CAP_STATE_WAIT_OUTGOING_SECURITY_LEVEL_UPDATE: 2649 case L2CAP_STATE_WAIT_CLIENT_ACCEPT_OR_REJECT: 2650 case L2CAP_STATE_WAIT_OUTGOING_EXTENDED_FEATURES: 2651 case L2CAP_STATE_WAIT_CONNECT_RSP: 2652 case L2CAP_STATE_CONFIG: 2653 case L2CAP_STATE_WILL_SEND_CONNECTION_REQUEST: 2654 case L2CAP_STATE_WILL_SEND_LE_CONNECTION_REQUEST: 2655 case L2CAP_STATE_WAIT_LE_CONNECTION_RESPONSE: 2656 case L2CAP_STATE_EMIT_OPEN_FAILED_AND_DISCARD: 2657 return 1; 2658 2659 case L2CAP_STATE_OPEN: 2660 case L2CAP_STATE_CLOSED: 2661 case L2CAP_STATE_WAIT_INCOMING_EXTENDED_FEATURES: 2662 case L2CAP_STATE_WAIT_DISCONNECT: 2663 case L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_INSUFFICIENT_SECURITY: 2664 case L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_DECLINE: 2665 case L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_ACCEPT: 2666 case L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST: 2667 case L2CAP_STATE_WILL_SEND_DISCONNECT_RESPONSE: 2668 case L2CAP_STATE_WILL_SEND_LE_CONNECTION_RESPONSE_DECLINE: 2669 case L2CAP_STATE_WILL_SEND_LE_CONNECTION_RESPONSE_ACCEPT: 2670 case L2CAP_STATE_INVALID: 2671 case L2CAP_STATE_WAIT_INCOMING_SECURITY_LEVEL_UPDATE: 2672 return 0; 2673 2674 default: 2675 // get a "warning" about new states 2676 btstack_assert(false); 2677 return 0; 2678 } 2679 } 2680 #endif 2681 2682 #ifdef ENABLE_CLASSIC 2683 static void l2cap_handle_hci_disconnect_event(l2cap_channel_t * channel){ 2684 if (l2cap_send_open_failed_on_hci_disconnect(channel)){ 2685 l2cap_handle_channel_open_failed(channel, L2CAP_CONNECTION_BASEBAND_DISCONNECT); 2686 } else { 2687 l2cap_handle_channel_closed(channel); 2688 } 2689 l2cap_free_channel_entry(channel); 2690 } 2691 #endif 2692 2693 #ifdef ENABLE_L2CAP_LE_CREDIT_BASED_FLOW_CONTROL_MODE 2694 static void l2cap_handle_hci_le_disconnect_event(l2cap_channel_t * channel){ 2695 if (l2cap_send_open_failed_on_hci_disconnect(channel)){ 2696 l2cap_cbm_emit_channel_opened(channel, L2CAP_CONNECTION_BASEBAND_DISCONNECT); 2697 } else { 2698 l2cap_cbm_emit_channel_closed(channel); 2699 } 2700 l2cap_free_channel_entry(channel); 2701 } 2702 #endif 2703 2704 #ifdef ENABLE_CLASSIC 2705 static void l2cap_check_classic_timeout(hci_con_handle_t handle){ 2706 if (gap_get_connection_type(handle) != GAP_CONNECTION_ACL) { 2707 return; 2708 } 2709 if (hci_authentication_active_for_handle(handle)) { 2710 return; 2711 } 2712 bool hci_con_used = false; 2713 btstack_linked_list_iterator_t it; 2714 btstack_linked_list_iterator_init(&it, &l2cap_channels); 2715 while (btstack_linked_list_iterator_has_next(&it)){ 2716 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 2717 if (!l2cap_is_dynamic_channel_type(channel->channel_type)) continue; 2718 if (channel->con_handle != handle) continue; 2719 hci_con_used = true; 2720 break; 2721 } 2722 if (hci_con_used) { 2723 return; 2724 } 2725 if (!hci_can_send_command_packet_now()) { 2726 return; 2727 } 2728 hci_send_cmd(&hci_disconnect, handle, 0x13); // remote closed connection 2729 } 2730 2731 static void l2cap_handle_features_complete(hci_con_handle_t handle){ 2732 if (hci_remote_features_available(handle) == false){ 2733 return; 2734 } 2735 btstack_linked_list_iterator_t it; 2736 btstack_linked_list_iterator_init(&it, &l2cap_channels); 2737 while (btstack_linked_list_iterator_has_next(&it)){ 2738 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 2739 if (!l2cap_is_dynamic_channel_type(channel->channel_type)) continue; 2740 if (channel->con_handle != handle) continue; 2741 log_info("remote supported features, channel %p, cid %04x - state %u", channel, channel->local_cid, channel->state); 2742 l2cap_handle_remote_supported_features_received(channel); 2743 } 2744 } 2745 2746 static void l2cap_handle_security_level_incoming_sufficient(l2cap_channel_t * channel){ 2747 channel->state = L2CAP_STATE_WAIT_CLIENT_ACCEPT_OR_REJECT; 2748 l2cap_emit_incoming_connection(channel); 2749 } 2750 2751 static void l2cap_handle_security_level(hci_con_handle_t handle, gap_security_level_t actual_level){ 2752 log_info("security level update for handle 0x%04x", handle); 2753 2754 // trigger l2cap information requests 2755 if (actual_level > LEVEL_0){ 2756 hci_connection_t * hci_connection = hci_connection_for_handle(handle); 2757 btstack_assert(hci_connection != NULL); 2758 if (hci_connection->l2cap_state.information_state == L2CAP_INFORMATION_STATE_IDLE){ 2759 hci_connection->l2cap_state.information_state = L2CAP_INFORMATION_STATE_W2_SEND_EXTENDED_FEATURE_REQUEST; 2760 } 2761 } 2762 2763 btstack_linked_list_iterator_t it; 2764 btstack_linked_list_iterator_init(&it, &l2cap_channels); 2765 while (btstack_linked_list_iterator_has_next(&it)){ 2766 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 2767 if (!l2cap_is_dynamic_channel_type(channel->channel_type)) continue; 2768 if (channel->con_handle != handle) continue; 2769 2770 gap_security_level_t required_level = channel->required_security_level; 2771 2772 log_info("channel %p, cid %04x - state %u: actual %u >= required %u?", channel, channel->local_cid, channel->state, actual_level, required_level); 2773 2774 switch (channel->state){ 2775 case L2CAP_STATE_WAIT_INCOMING_SECURITY_LEVEL_UPDATE: 2776 if (actual_level >= required_level){ 2777 l2cap_handle_security_level_incoming_sufficient(channel); 2778 } else { 2779 channel->reason = L2CAP_CONNECTION_RESULT_SECURITY_BLOCK; 2780 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_DECLINE; 2781 } 2782 break; 2783 2784 case L2CAP_STATE_WAIT_OUTGOING_SECURITY_LEVEL_UPDATE: 2785 if (actual_level >= required_level){ 2786 l2cap_ready_to_connect(channel); 2787 } else { 2788 // security level insufficient, report error and free channel 2789 l2cap_handle_channel_open_failed(channel, L2CAP_CONNECTION_RESPONSE_RESULT_REFUSED_SECURITY); 2790 btstack_linked_list_remove(&l2cap_channels, (btstack_linked_item_t *) channel); 2791 l2cap_free_channel_entry(channel); 2792 } 2793 break; 2794 2795 default: 2796 break; 2797 } 2798 } 2799 } 2800 #endif 2801 2802 #ifdef L2CAP_USES_CHANNELS 2803 static void l2cap_handle_disconnection_complete(hci_con_handle_t handle){ 2804 // collect channels to close 2805 btstack_linked_list_t channels_to_close = NULL; 2806 btstack_linked_list_iterator_t it; 2807 btstack_linked_list_iterator_init(&it, &l2cap_channels); 2808 while (btstack_linked_list_iterator_has_next(&it)) { 2809 l2cap_channel_t *channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 2810 if (!l2cap_is_dynamic_channel_type(channel->channel_type)) continue; 2811 if (channel->con_handle != handle) continue; 2812 btstack_linked_list_iterator_remove(&it); 2813 btstack_linked_list_add(&channels_to_close, (btstack_linked_item_t *) channel); 2814 } 2815 // send l2cap open failed or closed events for all channels on this handle and free them 2816 btstack_linked_list_iterator_init(&it, &channels_to_close); 2817 while (btstack_linked_list_iterator_has_next(&it)) { 2818 l2cap_channel_t *channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 2819 btstack_linked_list_iterator_remove(&it); 2820 switch(channel->channel_type){ 2821 #ifdef ENABLE_CLASSIC 2822 case L2CAP_CHANNEL_TYPE_CLASSIC: 2823 l2cap_handle_hci_disconnect_event(channel); 2824 break; 2825 #endif 2826 #ifdef ENABLE_L2CAP_LE_CREDIT_BASED_FLOW_CONTROL_MODE 2827 case L2CAP_CHANNEL_TYPE_CHANNEL_CBM: 2828 l2cap_handle_hci_le_disconnect_event(channel); 2829 break; 2830 #endif 2831 #ifdef ENABLE_L2CAP_ENHANCED_CREDIT_BASED_FLOW_CONTROL_MODE 2832 case L2CAP_CHANNEL_TYPE_CHANNEL_ECBM: 2833 switch (channel->state) { 2834 case L2CAP_STATE_WILL_SEND_ENHANCED_CONNECTION_REQUEST: 2835 case L2CAP_STATE_WAIT_ENHANCED_CONNECTION_RESPONSE: 2836 // emit open failed if disconnected before connection complete 2837 l2cap_ecbm_emit_channel_opened(channel, L2CAP_CONNECTION_BASEBAND_DISCONNECT); 2838 break; 2839 case L2CAP_STATE_WILL_SEND_EHNANCED_RENEGOTIATION_REQUEST: 2840 case L2CAP_STATE_WAIT_ENHANCED_RENEGOTIATION_RESPONSE: 2841 // emit reconfigure failure - result = 0xffff 2842 l2cap_ecbm_emit_reconfigure_complete(channel, 0xffff); 2843 break; 2844 default: 2845 l2cap_emit_simple_event_with_cid(channel, L2CAP_EVENT_ECBM_CHANNEL_CLOSED); 2846 break; 2847 } 2848 l2cap_free_channel_entry(channel); 2849 break; 2850 #endif 2851 default: 2852 break; 2853 } 2854 } 2855 } 2856 #endif 2857 2858 static void l2cap_hci_event_handler(uint8_t packet_type, uint16_t cid, uint8_t *packet, uint16_t size){ 2859 2860 UNUSED(packet_type); // ok: registered with hci_event_callback_registration 2861 UNUSED(cid); // ok: there is no channel 2862 UNUSED(size); // ok: fixed format events read from HCI buffer 2863 2864 #ifdef ENABLE_CLASSIC 2865 bd_addr_t address; 2866 gap_security_level_t security_level; 2867 #endif 2868 #ifdef L2CAP_USES_CHANNELS 2869 hci_con_handle_t handle; 2870 #endif 2871 2872 switch(hci_event_packet_get_type(packet)){ 2873 2874 // Notify channel packet handler if they can send now 2875 case HCI_EVENT_TRANSPORT_PACKET_SENT: 2876 case HCI_EVENT_NUMBER_OF_COMPLETED_PACKETS: 2877 case BTSTACK_EVENT_NR_CONNECTIONS_CHANGED: 2878 l2cap_call_notify_channel_in_run = true; 2879 break; 2880 2881 case HCI_EVENT_COMMAND_STATUS: 2882 #ifdef ENABLE_CLASSIC 2883 // check command status for create connection for errors 2884 if (HCI_EVENT_IS_COMMAND_STATUS(packet, hci_create_connection)){ 2885 // cache outgoing address and reset 2886 (void)memcpy(address, l2cap_outgoing_classic_addr, 6); 2887 memset(l2cap_outgoing_classic_addr, 0, 6); 2888 // error => outgoing connection failed 2889 uint8_t status = hci_event_command_status_get_status(packet); 2890 if (status){ 2891 l2cap_handle_connection_failed_for_addr(address, status); 2892 } 2893 } 2894 #endif 2895 l2cap_run(); // try sending signaling packets first 2896 break; 2897 2898 #ifdef ENABLE_CLASSIC 2899 // handle connection complete events 2900 case HCI_EVENT_CONNECTION_COMPLETE: 2901 reverse_bd_addr(&packet[5], address); 2902 if (packet[2] == 0){ 2903 handle = little_endian_read_16(packet, 3); 2904 l2cap_handle_connection_success_for_addr(address, handle); 2905 } else { 2906 l2cap_handle_connection_failed_for_addr(address, packet[2]); 2907 } 2908 break; 2909 2910 // handle successful create connection cancel command 2911 case HCI_EVENT_COMMAND_COMPLETE: 2912 if (HCI_EVENT_IS_COMMAND_COMPLETE(packet, hci_create_connection_cancel)) { 2913 if (packet[5] == 0){ 2914 reverse_bd_addr(&packet[6], address); 2915 // CONNECTION TERMINATED BY LOCAL HOST (0X16) 2916 l2cap_handle_connection_failed_for_addr(address, 0x16); 2917 } 2918 } 2919 l2cap_run(); // try sending signaling packets first 2920 break; 2921 #endif 2922 2923 #ifdef L2CAP_USES_CHANNELS 2924 // handle disconnection complete events 2925 case HCI_EVENT_DISCONNECTION_COMPLETE: 2926 handle = little_endian_read_16(packet, 3); 2927 l2cap_handle_disconnection_complete(handle); 2928 break; 2929 #endif 2930 2931 // HCI Connection Timeouts 2932 #ifdef ENABLE_CLASSIC 2933 case L2CAP_EVENT_TIMEOUT_CHECK: 2934 handle = little_endian_read_16(packet, 2); 2935 l2cap_check_classic_timeout(handle); 2936 break; 2937 2938 case HCI_EVENT_READ_REMOTE_SUPPORTED_FEATURES_COMPLETE: 2939 case HCI_EVENT_READ_REMOTE_EXTENDED_FEATURES_COMPLETE: 2940 handle = little_endian_read_16(packet, 3); 2941 l2cap_handle_features_complete(handle); 2942 break; 2943 2944 case GAP_EVENT_SECURITY_LEVEL: 2945 handle = little_endian_read_16(packet, 2); 2946 security_level = (gap_security_level_t) packet[4]; 2947 l2cap_handle_security_level(handle, security_level); 2948 break; 2949 #endif 2950 default: 2951 break; 2952 } 2953 2954 l2cap_run(); 2955 } 2956 2957 static void l2cap_register_signaling_response(hci_con_handle_t handle, uint8_t code, uint8_t sig_id, uint16_t cid, uint16_t data){ 2958 // Vol 3, Part A, 4.3: "The DCID and SCID fields shall be ignored when the result field indicates the connection was refused." 2959 if (l2cap_signaling_responses_pending < NR_PENDING_SIGNALING_RESPONSES) { 2960 l2cap_signaling_responses[l2cap_signaling_responses_pending].handle = handle; 2961 l2cap_signaling_responses[l2cap_signaling_responses_pending].code = code; 2962 l2cap_signaling_responses[l2cap_signaling_responses_pending].sig_id = sig_id; 2963 l2cap_signaling_responses[l2cap_signaling_responses_pending].cid = cid; 2964 l2cap_signaling_responses[l2cap_signaling_responses_pending].data = data; 2965 l2cap_signaling_responses_pending++; 2966 l2cap_run(); 2967 } 2968 } 2969 2970 #ifdef ENABLE_CLASSIC 2971 static void l2cap_handle_disconnect_request(l2cap_channel_t *channel, uint16_t identifier){ 2972 switch (channel->state){ 2973 case L2CAP_STATE_CONFIG: 2974 case L2CAP_STATE_OPEN: 2975 case L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST: 2976 case L2CAP_STATE_WAIT_DISCONNECT: 2977 break; 2978 default: 2979 // ignore in other states 2980 return; 2981 } 2982 2983 channel->remote_sig_id = identifier; 2984 channel->state = L2CAP_STATE_WILL_SEND_DISCONNECT_RESPONSE; 2985 l2cap_run(); 2986 } 2987 2988 static void l2cap_handle_connection_request(hci_con_handle_t handle, uint8_t sig_id, uint16_t psm, uint16_t source_cid){ 2989 2990 // log_info("l2cap_handle_connection_request for handle %u, psm %u cid 0x%02x", handle, psm, source_cid); 2991 l2cap_service_t *service = l2cap_get_service(psm); 2992 if (!service) { 2993 l2cap_register_signaling_response(handle, CONNECTION_REQUEST, sig_id, source_cid, L2CAP_CONNECTION_RESULT_PSM_NOT_SUPPORTED); 2994 return; 2995 } 2996 2997 hci_connection_t * hci_connection = hci_connection_for_handle( handle ); 2998 if (!hci_connection) { 2999 // 3000 log_error("no hci_connection for handle %u", handle); 3001 return; 3002 } 3003 3004 // alloc structure 3005 gap_security_level_t required_level = service->required_security_level; 3006 if (gap_get_secure_connections_only_mode() && (required_level != LEVEL_0)){ 3007 required_level = LEVEL_4; 3008 } 3009 l2cap_channel_t * channel = l2cap_create_channel_entry(service->packet_handler, L2CAP_CHANNEL_TYPE_CLASSIC, hci_connection->address, BD_ADDR_TYPE_ACL, 3010 psm, service->mtu, required_level); 3011 if (!channel){ 3012 l2cap_register_signaling_response(handle, CONNECTION_REQUEST, sig_id, source_cid, L2CAP_CONNECTION_RESULT_NO_RESOURCES_AVAILABLE); 3013 return; 3014 } 3015 3016 channel->con_handle = handle; 3017 channel->remote_cid = source_cid; 3018 channel->remote_sig_id = sig_id; 3019 3020 // limit local mtu to max acl packet length - l2cap header 3021 if (channel->local_mtu > l2cap_max_mtu()) { 3022 channel->local_mtu = l2cap_max_mtu(); 3023 } 3024 3025 // set initial state 3026 channel->state = L2CAP_STATE_WAIT_REMOTE_SUPPORTED_FEATURES; 3027 channel->state_var = L2CAP_CHANNEL_STATE_VAR_INCOMING; 3028 3029 // add to connections list 3030 btstack_linked_list_add_tail(&l2cap_channels, (btstack_linked_item_t *) channel); 3031 3032 // 3033 if (required_level > LEVEL_0){ 3034 // send conn resp pending if remote supported features have not been received yet 3035 if (hci_remote_features_available(handle)) { 3036 l2cap_handle_remote_supported_features_received(channel); 3037 } else { 3038 channel->state_var |= L2CAP_CHANNEL_STATE_VAR_SEND_CONN_RESP_PEND; 3039 hci_remote_features_query(handle); 3040 } 3041 } else { 3042 l2cap_handle_security_level_incoming_sufficient(channel); 3043 } 3044 } 3045 3046 void l2cap_accept_connection(uint16_t local_cid){ 3047 log_info("L2CAP_ACCEPT_CONNECTION local_cid 0x%x", local_cid); 3048 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 3049 if (!channel) { 3050 log_error("accept called but local_cid 0x%x not found", local_cid); 3051 return; 3052 } 3053 3054 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 3055 // configure L2CAP Basic mode 3056 channel->mode = L2CAP_CHANNEL_MODE_BASIC; 3057 #endif 3058 3059 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_ACCEPT; 3060 3061 // process 3062 l2cap_run(); 3063 } 3064 3065 void l2cap_decline_connection(uint16_t local_cid){ 3066 log_info("decline local_cid 0x%x", local_cid); 3067 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid( local_cid); 3068 if (!channel) { 3069 log_error( "l2cap_decline_connection called but local_cid 0x%x not found", local_cid); 3070 return; 3071 } 3072 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_DECLINE; 3073 channel->reason = L2CAP_CONNECTION_RESULT_NO_RESOURCES_AVAILABLE; 3074 l2cap_run(); 3075 } 3076 3077 // @pre command len is valid, see check in l2cap_signaling_handler_channel 3078 static void l2cap_signaling_handle_configure_request(l2cap_channel_t *channel, uint8_t *command){ 3079 3080 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 3081 uint8_t use_fcs = 1; 3082 #endif 3083 3084 channel->remote_sig_id = command[L2CAP_SIGNALING_COMMAND_SIGID_OFFSET]; 3085 3086 uint16_t flags = little_endian_read_16(command, 6); 3087 if (flags & 1) { 3088 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_CONT); 3089 } 3090 3091 // accept the other's configuration options 3092 uint16_t end_pos = 4 + little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_LENGTH_OFFSET); 3093 uint16_t pos = 8; 3094 while (pos < end_pos){ 3095 uint8_t option_hint = command[pos] >> 7; 3096 uint8_t option_type = command[pos] & 0x7f; 3097 // log_info("l2cap cid %u, hint %u, type %u", channel->local_cid, option_hint, option_type); 3098 pos++; 3099 uint8_t length = command[pos++]; 3100 // MTU { type(8): 1, len(8):2, MTU(16) } 3101 if ((option_type == L2CAP_CONFIG_OPTION_TYPE_MAX_TRANSMISSION_UNIT) && (length == 2)){ 3102 channel->remote_mtu = little_endian_read_16(command, pos); 3103 log_info("Remote MTU %u", channel->remote_mtu); 3104 if (channel->remote_mtu > l2cap_max_mtu()){ 3105 log_info("Remote MTU %u larger than outgoing buffer, only using MTU = %u", channel->remote_mtu, l2cap_max_mtu()); 3106 channel->remote_mtu = l2cap_max_mtu(); 3107 } 3108 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_MTU); 3109 } 3110 // Flush timeout { type(8):2, len(8): 2, Flush Timeout(16)} 3111 if ((option_type == L2CAP_CONFIG_OPTION_TYPE_FLUSH_TIMEOUT) && (length == 2)){ 3112 channel->flush_timeout = little_endian_read_16(command, pos); 3113 log_info("Flush timeout: %u ms", channel->flush_timeout); 3114 } 3115 3116 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 3117 // Retransmission and Flow Control Option 3118 if (option_type == L2CAP_CONFIG_OPTION_TYPE_RETRANSMISSION_AND_FLOW_CONTROL && length == 9){ 3119 l2cap_channel_mode_t mode = (l2cap_channel_mode_t) command[pos]; 3120 switch(channel->mode){ 3121 case L2CAP_CHANNEL_MODE_ENHANCED_RETRANSMISSION: 3122 // Store remote config 3123 channel->remote_tx_window_size = command[pos+1]; 3124 channel->remote_max_transmit = command[pos+2]; 3125 channel->remote_retransmission_timeout_ms = little_endian_read_16(command, pos + 3); 3126 channel->remote_monitor_timeout_ms = little_endian_read_16(command, pos + 5); 3127 channel->remote_mps = little_endian_read_16(command, pos + 7); 3128 log_info("FC&C config: tx window: %u, max transmit %u, retrans timeout %u, monitor timeout %u, mps %u", 3129 channel->remote_tx_window_size, 3130 channel->remote_max_transmit, 3131 channel->remote_retransmission_timeout_ms, 3132 channel->remote_monitor_timeout_ms, 3133 channel->remote_mps); 3134 // If ERTM mandatory, but remote doens't offer ERTM -> disconnect 3135 if (channel->ertm_mandatory && mode != L2CAP_CHANNEL_MODE_ENHANCED_RETRANSMISSION){ 3136 channel->state = L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST; 3137 } else { 3138 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_ERTM); 3139 } 3140 break; 3141 case L2CAP_CHANNEL_MODE_BASIC: 3142 switch (mode){ 3143 case L2CAP_CHANNEL_MODE_ENHANCED_RETRANSMISSION: 3144 // remote asks for ERTM, but we want basic mode. disconnect if this happens a second time 3145 if (channel->state_var & L2CAP_CHANNEL_STATE_VAR_BASIC_FALLBACK_TRIED){ 3146 channel->state = L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST; 3147 } 3148 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_BASIC_FALLBACK_TRIED); 3149 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_REJECTED); 3150 break; 3151 default: // case L2CAP_CHANNEL_MODE_BASIC: 3152 // TODO store and evaluate configuration 3153 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_ERTM); 3154 break; 3155 } 3156 break; 3157 default: 3158 break; 3159 } 3160 } 3161 if (option_type == L2CAP_CONFIG_OPTION_TYPE_FRAME_CHECK_SEQUENCE && length == 1){ 3162 use_fcs = command[pos]; 3163 } 3164 #endif 3165 // check for unknown options 3166 if ((option_hint == 0) && ((option_type < L2CAP_CONFIG_OPTION_TYPE_MAX_TRANSMISSION_UNIT) || (option_type > L2CAP_CONFIG_OPTION_TYPE_EXTENDED_WINDOW_SIZE))){ 3167 log_info("l2cap cid %u, unknown option 0x%02x", channel->local_cid, option_type); 3168 channel->unknown_option = option_type; 3169 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_INVALID); 3170 } 3171 pos += length; 3172 } 3173 3174 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 3175 // "FCS" has precedence over "No FCS" 3176 uint8_t update = channel->fcs_option || use_fcs; 3177 log_info("local fcs: %u, remote fcs: %u -> %u", channel->fcs_option, use_fcs, update); 3178 channel->fcs_option = update; 3179 // If ERTM mandatory, but remote didn't send Retransmission and Flowcontrol options -> disconnect 3180 if (((channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_ERTM) == 0) & (channel->ertm_mandatory)){ 3181 channel->state = L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST; 3182 } 3183 #endif 3184 } 3185 3186 // @pre command len is valid, see check in l2cap_signaling_handler_channel 3187 static void l2cap_signaling_handle_configure_response(l2cap_channel_t *channel, uint8_t result, uint8_t *command){ 3188 log_info("l2cap_signaling_handle_configure_response"); 3189 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 3190 uint16_t end_pos = 4 + little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_LENGTH_OFFSET); 3191 uint16_t pos = 10; 3192 while (pos < end_pos){ 3193 uint8_t option_hint = command[pos] >> 7; 3194 uint8_t option_type = command[pos] & 0x7f; 3195 // log_info("l2cap cid %u, hint %u, type %u", channel->local_cid, option_hint, option_type); 3196 pos++; 3197 uint8_t length = command[pos++]; 3198 3199 // Retransmission and Flow Control Option 3200 if (option_type == L2CAP_CONFIG_OPTION_TYPE_RETRANSMISSION_AND_FLOW_CONTROL && length == 9){ 3201 switch (channel->mode){ 3202 case L2CAP_CHANNEL_MODE_ENHANCED_RETRANSMISSION: 3203 if (channel->ertm_mandatory){ 3204 // ?? 3205 } else { 3206 // On 'Reject - Unacceptable Parameters' to our optional ERTM request, fall back to BASIC mode 3207 if (result == L2CAP_CONF_RESULT_UNACCEPTABLE_PARAMETERS){ 3208 l2cap_emit_simple_event_with_cid(channel, L2CAP_EVENT_ERTM_BUFFER_RELEASED); 3209 channel->mode = L2CAP_CHANNEL_MODE_BASIC; 3210 } 3211 } 3212 break; 3213 case L2CAP_CHANNEL_MODE_BASIC: 3214 if (result == L2CAP_CONF_RESULT_UNACCEPTABLE_PARAMETERS){ 3215 // On 'Reject - Unacceptable Parameters' to our Basic mode request, disconnect 3216 channel->state = L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST; 3217 } 3218 break; 3219 default: 3220 break; 3221 } 3222 } 3223 3224 // check for unknown options 3225 if (option_hint == 0 && (option_type < L2CAP_CONFIG_OPTION_TYPE_MAX_TRANSMISSION_UNIT || option_type > L2CAP_CONFIG_OPTION_TYPE_EXTENDED_WINDOW_SIZE)){ 3226 log_info("l2cap cid %u, unknown option 0x%02x", channel->local_cid, option_type); 3227 channel->unknown_option = option_type; 3228 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_INVALID); 3229 } 3230 3231 pos += length; 3232 } 3233 #else 3234 UNUSED(channel); // ok: no code 3235 UNUSED(result); // ok: no code 3236 UNUSED(command); // ok: no code 3237 #endif 3238 } 3239 3240 static int l2cap_channel_ready_for_open(l2cap_channel_t *channel){ 3241 // log_info("l2cap_channel_ready_for_open 0x%02x", channel->state_var); 3242 if ((channel->state_var & L2CAP_CHANNEL_STATE_VAR_RCVD_CONF_RSP) == 0) return 0; 3243 if ((channel->state_var & L2CAP_CHANNEL_STATE_VAR_SENT_CONF_RSP) == 0) return 0; 3244 // addition check that fixes re-entrance issue causing l2cap event channel opened twice 3245 if (channel->state == L2CAP_STATE_OPEN) return 0; 3246 return 1; 3247 } 3248 3249 3250 // @pre command len is valid, see check in l2cap_signaling_handler_dispatch 3251 static void l2cap_signaling_handler_channel(l2cap_channel_t *channel, uint8_t *command){ 3252 3253 uint8_t code = command[L2CAP_SIGNALING_COMMAND_CODE_OFFSET]; 3254 uint8_t identifier = command[L2CAP_SIGNALING_COMMAND_SIGID_OFFSET]; 3255 uint16_t cmd_len = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_LENGTH_OFFSET); 3256 uint16_t result = 0; 3257 3258 log_info("L2CAP signaling handler code %u, state %u", code, channel->state); 3259 3260 // handle DISCONNECT REQUESTS seperately 3261 if (code == DISCONNECTION_REQUEST){ 3262 l2cap_handle_disconnect_request(channel, identifier); 3263 return; 3264 } 3265 3266 // @STATEMACHINE(l2cap) 3267 switch (channel->state) { 3268 3269 case L2CAP_STATE_WAIT_CONNECT_RSP: 3270 switch (code){ 3271 case CONNECTION_RESPONSE: 3272 if (cmd_len < 8){ 3273 // command imcomplete 3274 l2cap_register_signaling_response(channel->con_handle, COMMAND_REJECT, identifier, 0, L2CAP_REJ_CMD_UNKNOWN); 3275 break; 3276 } 3277 l2cap_stop_rtx(channel); 3278 result = little_endian_read_16 (command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET+4); 3279 switch (result) { 3280 case 0: 3281 // successful connection 3282 channel->remote_cid = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 3283 channel->state = L2CAP_STATE_CONFIG; 3284 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ); 3285 break; 3286 case 1: 3287 // connection pending. get some coffee, but start the ERTX 3288 l2cap_start_ertx(channel); 3289 break; 3290 default: 3291 // channel closed 3292 channel->state = L2CAP_STATE_CLOSED; 3293 // map l2cap connection response result to BTstack status enumeration 3294 l2cap_handle_channel_open_failed(channel, L2CAP_CONNECTION_RESPONSE_RESULT_SUCCESSFUL + result); 3295 3296 // drop link key if security block 3297 if ((L2CAP_CONNECTION_RESPONSE_RESULT_SUCCESSFUL + result) == L2CAP_CONNECTION_RESPONSE_RESULT_REFUSED_SECURITY){ 3298 gap_drop_link_key_for_bd_addr(channel->address); 3299 } 3300 3301 // discard channel 3302 btstack_linked_list_remove(&l2cap_channels, (btstack_linked_item_t *) channel); 3303 l2cap_free_channel_entry(channel); 3304 break; 3305 } 3306 break; 3307 3308 default: 3309 //@TODO: implement other signaling packets 3310 break; 3311 } 3312 break; 3313 3314 case L2CAP_STATE_CONFIG: 3315 switch (code) { 3316 case CONFIGURE_REQUEST: 3317 if (cmd_len < 4){ 3318 // command incomplete 3319 l2cap_register_signaling_response(channel->con_handle, COMMAND_REJECT, identifier, 0, L2CAP_REJ_CMD_UNKNOWN); 3320 break; 3321 } 3322 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP); 3323 l2cap_signaling_handle_configure_request(channel, command); 3324 if (!(channel->state_var & L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_CONT)){ 3325 // only done if continuation not set 3326 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_RCVD_CONF_REQ); 3327 } 3328 break; 3329 case CONFIGURE_RESPONSE: 3330 if (cmd_len < 6){ 3331 // command incomplete 3332 l2cap_register_signaling_response(channel->con_handle, COMMAND_REJECT, identifier, 0, L2CAP_REJ_CMD_UNKNOWN); 3333 break; 3334 } 3335 result = little_endian_read_16 (command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET+4); 3336 l2cap_stop_rtx(channel); 3337 l2cap_signaling_handle_configure_response(channel, result, command); 3338 switch (result){ 3339 case 0: // success 3340 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_RCVD_CONF_RSP); 3341 break; 3342 case 4: // pending 3343 l2cap_start_ertx(channel); 3344 break; 3345 default: 3346 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 3347 if (channel->mode == L2CAP_CHANNEL_MODE_ENHANCED_RETRANSMISSION && channel->ertm_mandatory){ 3348 // remote does not offer ertm but it's required 3349 channel->state = L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST; 3350 break; 3351 } 3352 #endif 3353 // retry on negative result 3354 channelStateVarSetFlag(channel, L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ); 3355 break; 3356 } 3357 break; 3358 default: 3359 break; 3360 } 3361 if (l2cap_channel_ready_for_open(channel)){ 3362 3363 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 3364 // assert that packet can be stored in fragment buffers in ertm 3365 if (channel->mode == L2CAP_CHANNEL_MODE_ENHANCED_RETRANSMISSION){ 3366 uint16_t effective_mps = btstack_min(channel->remote_mps, channel->local_mps); 3367 uint16_t usable_mtu = channel->num_tx_buffers == 1 ? effective_mps : channel->num_tx_buffers * effective_mps - 2; 3368 if (usable_mtu < channel->remote_mtu){ 3369 log_info("Remote MTU %u > max storable ERTM packet, only using MTU = %u", channel->remote_mtu, usable_mtu); 3370 channel->remote_mtu = usable_mtu; 3371 } 3372 } 3373 #endif 3374 // for open: 3375 channel->state = L2CAP_STATE_OPEN; 3376 l2cap_emit_channel_opened(channel, 0); 3377 } 3378 break; 3379 3380 case L2CAP_STATE_WAIT_DISCONNECT: 3381 switch (code) { 3382 case DISCONNECTION_RESPONSE: 3383 l2cap_finalize_channel_close(channel); 3384 break; 3385 default: 3386 //@TODO: implement other signaling packets 3387 break; 3388 } 3389 break; 3390 3391 case L2CAP_STATE_CLOSED: 3392 // @TODO handle incoming requests 3393 break; 3394 3395 case L2CAP_STATE_OPEN: 3396 //@TODO: implement other signaling packets, e.g. re-configure 3397 break; 3398 default: 3399 break; 3400 } 3401 // log_info("new state %u", channel->state); 3402 } 3403 3404 #ifdef ENABLE_CLASSIC 3405 static void l2cap_handle_information_request_complete(hci_connection_t * connection){ 3406 3407 connection->l2cap_state.information_state = L2CAP_INFORMATION_STATE_DONE; 3408 3409 // emit event 3410 uint8_t event[8]; 3411 event[0] = L2CAP_EVENT_INFORMATION_RESPONSE; 3412 event[1] = sizeof(event) - 2; 3413 little_endian_store_16(event, 2, connection->con_handle); 3414 little_endian_store_16(event, 4, connection->l2cap_state.extended_feature_mask); 3415 little_endian_store_16(event, 6, connection->l2cap_state.fixed_channels_supported); 3416 l2cap_emit_event(event, sizeof(event)); 3417 3418 // trigger connection request 3419 btstack_linked_list_iterator_t it; 3420 btstack_linked_list_iterator_init(&it, &l2cap_channels); 3421 while (btstack_linked_list_iterator_has_next(&it)){ 3422 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 3423 if (!l2cap_is_dynamic_channel_type(channel->channel_type)) continue; 3424 if (channel->con_handle != connection->con_handle) continue; 3425 3426 // incoming connection: information request was triggered after user has accepted connection, 3427 // now: verify channel configuration, esp. if ertm will be mandatory 3428 if (channel->state == L2CAP_STATE_WAIT_INCOMING_EXTENDED_FEATURES){ 3429 // default: continue 3430 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_ACCEPT; 3431 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 3432 if ((channel->mode == L2CAP_CHANNEL_MODE_ENHANCED_RETRANSMISSION) && ((connection->l2cap_state.extended_feature_mask & 0x08) == 0)){ 3433 // ERTM not possible, select basic mode and release buffer 3434 channel->mode = L2CAP_CHANNEL_MODE_BASIC; 3435 l2cap_emit_simple_event_with_cid(channel, L2CAP_EVENT_ERTM_BUFFER_RELEASED); 3436 3437 // bail if ERTM is mandatory 3438 if (channel->ertm_mandatory){ 3439 // We chose 'no resources available' for "ERTM mandatory but you don't even know ERTM exists" 3440 log_info("ERTM mandatory -> reject connection"); 3441 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_DECLINE; 3442 channel->reason = L2CAP_CONNECTION_RESULT_NO_RESOURCES_AVAILABLE; 3443 } else { 3444 log_info("ERTM not supported by remote -> use Basic mode"); 3445 } 3446 } 3447 #endif 3448 continue; 3449 } 3450 3451 // outgoing connection: information request is triggered before connection request 3452 if (channel->state == L2CAP_STATE_WAIT_OUTGOING_EXTENDED_FEATURES){ 3453 3454 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 3455 // if ERTM was requested, but is not listed in extended feature mask: 3456 if ((channel->mode == L2CAP_CHANNEL_MODE_ENHANCED_RETRANSMISSION) && ((connection->l2cap_state.extended_feature_mask & 0x08) == 0)){ 3457 3458 if (channel->ertm_mandatory){ 3459 // bail if ERTM is mandatory 3460 channel->state = L2CAP_STATE_CLOSED; 3461 // map l2cap connection response result to BTstack status enumeration 3462 l2cap_handle_channel_open_failed(channel, L2CAP_CONNECTION_RESPONSE_RESULT_ERTM_NOT_SUPPORTED); 3463 // discard channel 3464 btstack_linked_list_remove(&l2cap_channels, (btstack_linked_item_t *) channel); 3465 l2cap_free_channel_entry(channel); 3466 continue; 3467 3468 } else { 3469 // fallback to Basic mode 3470 l2cap_emit_simple_event_with_cid(channel, L2CAP_EVENT_ERTM_BUFFER_RELEASED); 3471 channel->mode = L2CAP_CHANNEL_MODE_BASIC; 3472 } 3473 } 3474 #endif 3475 3476 // respond to connection request 3477 channel->state = L2CAP_STATE_WILL_SEND_CONNECTION_REQUEST; 3478 continue; 3479 } 3480 } 3481 } 3482 #endif 3483 3484 // @pre command len is valid, see check in l2cap_acl_classic_handler 3485 static void l2cap_signaling_handler_dispatch(hci_con_handle_t handle, uint8_t * command){ 3486 3487 hci_connection_t * connection; 3488 btstack_linked_list_iterator_t it; 3489 3490 // get code, signal identifier and command len 3491 uint8_t code = command[L2CAP_SIGNALING_COMMAND_CODE_OFFSET]; 3492 uint8_t sig_id = command[L2CAP_SIGNALING_COMMAND_SIGID_OFFSET]; 3493 uint16_t cmd_len = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_LENGTH_OFFSET); 3494 3495 // general commands without an assigned channel 3496 switch(code) { 3497 3498 case CONNECTION_REQUEST: 3499 if (cmd_len == 4){ 3500 uint16_t psm = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 3501 uint16_t source_cid = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET+2); 3502 l2cap_handle_connection_request(handle, sig_id, psm, source_cid); 3503 } else { 3504 l2cap_register_signaling_response(handle, COMMAND_REJECT, sig_id, 0, L2CAP_REJ_CMD_UNKNOWN); 3505 } 3506 return; 3507 3508 case ECHO_REQUEST: 3509 l2cap_register_signaling_response(handle, code, sig_id, 0, 0); 3510 return; 3511 3512 case INFORMATION_REQUEST: 3513 if (cmd_len == 2) { 3514 uint16_t info_type = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 3515 l2cap_register_signaling_response(handle, code, sig_id, 0, info_type); 3516 return; 3517 } 3518 break; 3519 3520 case INFORMATION_RESPONSE: 3521 connection = hci_connection_for_handle(handle); 3522 if (!connection) return; 3523 switch (connection->l2cap_state.information_state){ 3524 case L2CAP_INFORMATION_STATE_W4_EXTENDED_FEATURE_RESPONSE: 3525 // get extended features from response if valid 3526 if (cmd_len >= 6) { 3527 uint16_t info_type = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 3528 uint16_t result = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET+2); 3529 if (result == 0 && info_type == L2CAP_INFO_TYPE_EXTENDED_FEATURES_SUPPORTED) { 3530 connection->l2cap_state.extended_feature_mask = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET+4); 3531 } 3532 log_info("extended features mask 0x%02x", connection->l2cap_state.extended_feature_mask); 3533 if ((connection->l2cap_state.extended_feature_mask & 0x80) != 0){ 3534 connection->l2cap_state.information_state = L2CAP_INFORMATION_STATE_W2_SEND_FIXED_CHANNELS_REQUEST; 3535 } else { 3536 // information request complete 3537 l2cap_handle_information_request_complete(connection); 3538 } 3539 } 3540 break; 3541 case L2CAP_INFORMATION_STATE_W4_FIXED_CHANNELS_RESPONSE: 3542 if (cmd_len >= 12) { 3543 uint16_t info_type = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 3544 uint16_t result = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET+2); 3545 if (result == 0 && info_type == L2CAP_INFO_TYPE_FIXED_CHANNELS_SUPPORTED) { 3546 connection->l2cap_state.fixed_channels_supported = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET + 4); 3547 } 3548 log_info("fixed channels mask 0x%02x", connection->l2cap_state.fixed_channels_supported); 3549 // information request complete 3550 l2cap_handle_information_request_complete(connection); 3551 } 3552 break; 3553 default: 3554 break; 3555 } 3556 return; 3557 3558 #ifdef ENABLE_L2CAP_ENHANCED_CREDIT_BASED_FLOW_CONTROL_MODE 3559 case L2CAP_CREDIT_BASED_CONNECTION_REQUEST: 3560 case L2CAP_CREDIT_BASED_CONNECTION_RESPONSE: 3561 case L2CAP_CREDIT_BASED_RECONFIGURE_REQUEST: 3562 case L2CAP_CREDIT_BASED_RECONFIGURE_RESPONSE: 3563 l2cap_ecbm_signaling_handler_dispatch(handle, L2CAP_CID_SIGNALING, command, sig_id); 3564 return; 3565 case L2CAP_FLOW_CONTROL_CREDIT_INDICATION: 3566 // return if valid 3567 if (l2cap_credit_based_handle_credit_indication(handle, command, cmd_len)) return; 3568 break; 3569 3570 case COMMAND_REJECT: 3571 btstack_linked_list_iterator_init(&it, &l2cap_channels); 3572 while (btstack_linked_list_iterator_has_next(&it)) { 3573 l2cap_channel_t *channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 3574 if (!l2cap_is_dynamic_channel_type(channel->channel_type)) continue; 3575 if (channel->con_handle != handle) continue; 3576 if (channel->local_sig_id != sig_id) continue; 3577 if (channel->state != L2CAP_STATE_WAIT_ENHANCED_CONNECTION_RESPONSE) continue; 3578 3579 // open failed 3580 channel->state = L2CAP_STATE_CLOSED; 3581 l2cap_ecbm_emit_channel_opened(channel, 3582 ERROR_CODE_CONNECTION_REJECTED_DUE_TO_LIMITED_RESOURCES); 3583 // drop failed channel 3584 btstack_linked_list_iterator_remove(&it); 3585 l2cap_free_channel_entry(channel); 3586 } 3587 break; 3588 #endif 3589 3590 default: 3591 break; 3592 } 3593 3594 // Get potential destination CID 3595 uint16_t dest_cid = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 3596 3597 // Find channel for this sig_id and connection handle 3598 btstack_linked_list_iterator_init(&it, &l2cap_channels); 3599 while (btstack_linked_list_iterator_has_next(&it)){ 3600 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 3601 if (!l2cap_is_dynamic_channel_type(channel->channel_type)) continue; 3602 if (channel->con_handle != handle) continue; 3603 if (code & 1) { 3604 // match odd commands (responses) by previous signaling identifier 3605 if (channel->local_sig_id == sig_id) { 3606 l2cap_signaling_handler_channel(channel, command); 3607 return; 3608 } 3609 } else { 3610 // match even commands (requests) by local channel id 3611 if (channel->local_cid == dest_cid) { 3612 l2cap_signaling_handler_channel(channel, command); 3613 return; 3614 } 3615 } 3616 } 3617 3618 // send command reject 3619 l2cap_register_signaling_response(handle, COMMAND_REJECT, sig_id, 0, L2CAP_REJ_CMD_UNKNOWN); 3620 } 3621 #endif 3622 3623 #ifdef L2CAP_USES_CHANNELS 3624 static l2cap_service_t * l2cap_get_service_internal(btstack_linked_list_t * services, uint16_t psm){ 3625 btstack_linked_list_iterator_t it; 3626 btstack_linked_list_iterator_init(&it, services); 3627 while (btstack_linked_list_iterator_has_next(&it)){ 3628 l2cap_service_t * service = (l2cap_service_t *) btstack_linked_list_iterator_next(&it); 3629 if ( service->psm == psm){ 3630 return service; 3631 }; 3632 } 3633 return NULL; 3634 } 3635 #endif 3636 3637 #ifdef ENABLE_L2CAP_ENHANCED_CREDIT_BASED_FLOW_CONTROL_MODE 3638 3639 static uint8_t l2cap_ecbm_setup_channels(btstack_linked_list_t * channels, 3640 btstack_packet_handler_t packet_handler, uint8_t num_channels, 3641 hci_connection_t * connection, uint16_t psm, uint16_t mtu, gap_security_level_t security_level){ 3642 uint8_t i; 3643 uint8_t status = ERROR_CODE_SUCCESS; 3644 for (i=0;i<num_channels;i++){ 3645 l2cap_channel_t * channel = l2cap_create_channel_entry(packet_handler, L2CAP_CHANNEL_TYPE_CHANNEL_ECBM, connection->address, connection->address_type, psm, mtu, security_level); 3646 if (!channel) { 3647 status = BTSTACK_MEMORY_ALLOC_FAILED; 3648 break; 3649 } 3650 channel->con_handle = connection->con_handle; 3651 btstack_linked_list_add_tail(channels, (btstack_linked_item_t *) channel); 3652 } 3653 3654 // free channels if not all allocated 3655 if (status != ERROR_CODE_SUCCESS){ 3656 while (true) { 3657 l2cap_channel_t * channel = (l2cap_channel_t *) btstack_linked_list_pop(channels); 3658 if (channel == NULL) break; 3659 l2cap_free_channel_entry(channel); 3660 } 3661 } 3662 3663 return status; 3664 } 3665 3666 static inline l2cap_service_t * l2cap_ecbm_get_service(uint16_t spsm){ 3667 return l2cap_get_service_internal(&l2cap_enhanced_services, spsm); 3668 } 3669 3670 static inline uint8_t l2cap_ecbm_status_for_result(uint16_t result) { 3671 switch (result) { 3672 case L2CAP_ECBM_CONNECTION_RESULT_ALL_SUCCESS: 3673 return ERROR_CODE_SUCCESS; 3674 case L2CAP_ECBM_CONNECTION_RESULT_ALL_REFUSED_SPSM_NOT_SUPPORTED: 3675 return L2CAP_CONNECTION_RESPONSE_RESULT_REFUSED_PSM; 3676 case L2CAP_ECBM_CONNECTION_RESULT_SOME_REFUSED_INSUFFICIENT_RESOURCES_AVAILABLE: 3677 return L2CAP_CONNECTION_RESPONSE_RESULT_REFUSED_RESOURCES; 3678 case L2CAP_ECBM_CONNECTION_RESULT_ALL_REFUSED_INSUFFICIENT_AUTHENTICATION: 3679 case L2CAP_ECBM_CONNECTION_RESULT_ALL_REFUSED_INSUFFICIENT_AUTHORIZATION: 3680 case L2CAP_ECBM_CONNECTION_RESULT_ALL_REFUSED_ENCYRPTION_KEY_SIZE_TOO_SHORT: 3681 case L2CAP_ECBM_CONNECTION_RESULT_ALL_REFUSED_INSUFFICIENT_ENCRYPTION: 3682 return L2CAP_CONNECTION_RESPONSE_RESULT_REFUSED_SECURITY; 3683 default: 3684 // invalid Source CID, Source CID already allocated, unacceptable parameters 3685 return L2CAP_CONNECTION_RESPONSE_UNKNOWN_ERROR; 3686 } 3687 } 3688 3689 static int l2cap_ecbm_signaling_handler_dispatch(hci_con_handle_t handle, uint16_t signaling_cid, uint8_t *command, 3690 uint8_t sig_id) { 3691 3692 hci_connection_t *connection; 3693 btstack_linked_list_iterator_t it; 3694 l2cap_service_t *service; 3695 uint16_t spsm; 3696 uint8_t num_channels; 3697 uint16_t num_channels_and_signaling_cid; 3698 uint8_t i; 3699 uint16_t new_mtu; 3700 uint16_t new_mps; 3701 uint16_t initial_credits; 3702 uint16_t result; 3703 uint8_t status; 3704 3705 uint8_t code = command[L2CAP_SIGNALING_COMMAND_CODE_OFFSET]; 3706 uint16_t len = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_LENGTH_OFFSET); 3707 log_info("enhanced dispatch: command 0x%02x, sig id %u, len %u", code, sig_id, len); 3708 3709 switch (code) { 3710 case L2CAP_CREDIT_BASED_CONNECTION_REQUEST: 3711 // check size 3712 if (len < 10u) return 0u; 3713 3714 // get hci connection, bail if not found (must not happen) 3715 connection = hci_connection_for_handle(handle); 3716 btstack_assert(connection != NULL); 3717 3718 // get num channels to establish 3719 num_channels = (len - 8) / sizeof(uint16_t); 3720 3721 // combine signaling cid and number channels for l2cap_register_signaling_response 3722 num_channels_and_signaling_cid = (num_channels << 8) | signaling_cid; 3723 3724 // check if service registered 3725 spsm = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 3726 service = l2cap_ecbm_get_service(spsm); 3727 3728 if (service) { 3729 3730 uint16_t remote_mtu = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET + 2); 3731 uint16_t remote_mps = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET + 4); 3732 uint16_t credits_outgoing = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET + 6); 3733 3734 // param: check remote mtu 3735 if (service->mtu > remote_mtu) { 3736 l2cap_register_signaling_response(handle, L2CAP_CREDIT_BASED_CONNECTION_REQUEST, sig_id, 3737 num_channels_and_signaling_cid, L2CAP_ECBM_CONNECTION_RESULT_ALL_REFUSED_INVALID_PARAMETERS); 3738 return 1; 3739 } 3740 3741 // security: check authentication 3742 if (service->required_security_level >= LEVEL_3) { 3743 if (!gap_authenticated(handle)) { 3744 l2cap_register_signaling_response(handle, L2CAP_CREDIT_BASED_CONNECTION_REQUEST, sig_id, 3745 num_channels_and_signaling_cid, L2CAP_ECBM_CONNECTION_RESULT_ALL_REFUSED_INSUFFICIENT_AUTHENTICATION); 3746 return 1; 3747 } 3748 } 3749 3750 // security: check encryption 3751 // L2CAP.TS.p31 does not check for Connection refused - insufficient encryption which might be send for no encryption 3752 if (service->required_security_level >= LEVEL_2) { 3753 if (gap_encryption_key_size(handle) < 16) { 3754 l2cap_register_signaling_response(handle, L2CAP_CREDIT_BASED_CONNECTION_REQUEST, sig_id, 3755 num_channels_and_signaling_cid, L2CAP_ECBM_CONNECTION_RESULT_ALL_REFUSED_ENCYRPTION_KEY_SIZE_TOO_SHORT); 3756 return 1; 3757 } 3758 } 3759 3760 // report the last result code != 0 3761 result = 0; 3762 // store one of the local cids for the event 3763 uint16_t a_local_cid = 0; 3764 for (i = 0; i < num_channels; i++) { 3765 3766 // check source cids 3767 uint16_t source_cid = little_endian_read_16(command, 12 + (i * 2)); 3768 if (source_cid < 0x40u) { 3769 result = L2CAP_ECBM_CONNECTION_RESULT_SOME_REFUSED_INVALID_SOURCE_CID; 3770 continue; 3771 } 3772 3773 // go through list of channels for this ACL connection and check if we get a match 3774 btstack_linked_list_iterator_init(&it, &l2cap_channels); 3775 bool source_cid_allocated = false; 3776 while (btstack_linked_list_iterator_has_next(&it)) { 3777 l2cap_channel_t *channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 3778 if (!l2cap_is_dynamic_channel_type(channel->channel_type)) continue; 3779 if (channel->con_handle != handle) continue; 3780 if (channel->remote_cid != source_cid) continue; 3781 source_cid_allocated = true; 3782 break; 3783 } 3784 if (source_cid_allocated) { 3785 result = 0x00a; 3786 continue; 3787 } 3788 3789 // setup channel 3790 l2cap_channel_t *channel = l2cap_create_channel_entry(service->packet_handler, 3791 L2CAP_CHANNEL_TYPE_CHANNEL_ECBM, 3792 connection->address, 3793 connection->address_type, spsm, 3794 service->mtu, 3795 service->required_security_level); 3796 3797 if (channel == NULL) { 3798 // Some connections refused – insufficient resources available 3799 result = 0x004; 3800 continue; 3801 } 3802 3803 // setup state 3804 channel->state = L2CAP_STATE_WAIT_CLIENT_ACCEPT_OR_REJECT; 3805 channel->state_var |= L2CAP_CHANNEL_STATE_VAR_INCOMING; 3806 channel->con_handle = connection->con_handle; 3807 channel->remote_sig_id = sig_id; 3808 channel->remote_cid = source_cid; 3809 channel->remote_mtu = remote_mtu; 3810 channel->remote_mps = remote_mps; 3811 channel->credits_outgoing = credits_outgoing; 3812 channel->cid_index = i; 3813 channel->num_cids = num_channels; 3814 3815 // if more than one error, we can report any of them 3816 channel->reason = result; 3817 3818 btstack_linked_list_add_tail(&l2cap_channels, (btstack_linked_item_t *) channel); 3819 3820 a_local_cid = channel->local_cid; 3821 } 3822 3823 // if no channels have been created, all have been refused, and we can respond right away 3824 if (a_local_cid == 0) { 3825 l2cap_register_signaling_response(handle, L2CAP_CREDIT_BASED_CONNECTION_REQUEST, sig_id, 3826 num_channels_and_signaling_cid, result); 3827 return 1; 3828 } 3829 3830 // emit incoming data connection event 3831 uint8_t event[16]; 3832 event[0] = L2CAP_EVENT_ECBM_INCOMING_CONNECTION; 3833 event[1] = sizeof(event) - 2; 3834 event[2] = connection->address_type; 3835 reverse_bd_addr(connection->address, &event[3]); 3836 little_endian_store_16(event, 9, connection->con_handle); 3837 little_endian_store_16(event, 11, spsm); 3838 event[13] = num_channels; 3839 little_endian_store_16(event, 14, a_local_cid); 3840 hci_dump_packet(HCI_EVENT_PACKET, 0, event, sizeof(event)); 3841 (*service->packet_handler)(HCI_EVENT_PACKET, a_local_cid, event, sizeof(event)); 3842 3843 } else { 3844 l2cap_register_signaling_response(handle, L2CAP_CREDIT_BASED_CONNECTION_REQUEST, sig_id, 3845 num_channels_and_signaling_cid, L2CAP_ECBM_CONNECTION_RESULT_ALL_REFUSED_SPSM_NOT_SUPPORTED); 3846 } 3847 return 1; 3848 3849 case L2CAP_CREDIT_BASED_CONNECTION_RESPONSE: 3850 // check size 3851 if (len < 10u) return 0u; 3852 3853 // get hci connection, ignore if not found 3854 connection = hci_connection_for_handle(handle); 3855 if (connection == NULL) return 0; 3856 3857 // get channel config: mtu, mps, initial credits, result 3858 new_mtu = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET + 0); 3859 new_mps = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET + 2); 3860 initial_credits = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET + 4); 3861 result = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET + 6); 3862 status = l2cap_ecbm_status_for_result(result); 3863 3864 // get num channels to modify 3865 num_channels = (len - 8) / sizeof(uint16_t); 3866 btstack_linked_list_iterator_init(&it, &l2cap_channels); 3867 while (btstack_linked_list_iterator_has_next(&it)) { 3868 l2cap_channel_t *channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 3869 if (!l2cap_is_dynamic_channel_type(channel->channel_type)) continue; 3870 if (channel->con_handle != handle) continue; 3871 if (channel->local_sig_id != sig_id) continue; 3872 if (channel->state != L2CAP_STATE_WAIT_ENHANCED_CONNECTION_RESPONSE) continue; 3873 if (channel->cid_index < num_channels) { 3874 uint16_t remote_cid = little_endian_read_16(command, 12 + channel->cid_index * sizeof(uint16_t)); 3875 if (remote_cid != 0) { 3876 channel->state = L2CAP_STATE_OPEN; 3877 channel->remote_cid = remote_cid; 3878 channel->remote_mtu = new_mtu; 3879 channel->remote_mps = new_mps; 3880 channel->credits_outgoing = initial_credits; 3881 l2cap_ecbm_emit_channel_opened(channel, ERROR_CODE_SUCCESS); 3882 continue; 3883 } 3884 } 3885 // open failed 3886 l2cap_ecbm_emit_channel_opened(channel, status); 3887 // drop failed channel 3888 btstack_linked_list_iterator_remove(&it); 3889 btstack_memory_l2cap_channel_free(channel); 3890 } 3891 return 1; 3892 3893 case L2CAP_CREDIT_BASED_RECONFIGURE_REQUEST: 3894 // check minimal size 3895 if (len < 6) return 0u; 3896 3897 // get hci connection, bail if not found (must not happen) 3898 connection = hci_connection_for_handle(handle); 3899 btstack_assert(connection != NULL); 3900 3901 // get num channels to modify 3902 num_channels = (len - 4) / sizeof(uint16_t); 3903 3904 // get new mtu and mps 3905 new_mtu = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET + 0); 3906 new_mps = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET + 2); 3907 3908 // validate request 3909 result = 0; 3910 for (i = 0; i < num_channels; i++) { 3911 // check cid 3912 uint16_t remote_cid = little_endian_read_16(command, 8 + (i * sizeof(uint16_t))); 3913 l2cap_channel_t *channel = l2cap_get_channel_for_remote_handle_and_cid(handle, remote_cid); 3914 if (channel == NULL) { 3915 result = L2CAP_ECBM_RECONFIGURE_FAILED_DESTINATION_CID_INVALID; 3916 break; 3917 } 3918 // check MTU is not reduced 3919 if (channel->remote_mtu > new_mtu) { 3920 result = L2CAP_ECBM_RECONFIGURE_FAILED_MTU_REDUCTION_NOT_ALLOWED; 3921 break; 3922 } 3923 // check MPS reduction 3924 if ((num_channels > 1) && (channel->remote_mps > new_mps)) { 3925 result = L2CAP_ECBM_RECONFIGURE_FAILED_MPS_REDUCTION_MULTIPLE_CHANNELS; 3926 break; 3927 } 3928 // check MPS valid 3929 if (new_mps < l2cap_enhanced_mps_min) { 3930 result = L2CAP_ECBM_RECONFIGURE_FAILED_UNACCEPTABLE_PARAMETERS; 3931 break; 3932 } 3933 } 3934 3935 // send reject 3936 if (result != 0) { 3937 l2cap_register_signaling_response(handle, L2CAP_CREDIT_BASED_RECONFIGURE_REQUEST, sig_id, signaling_cid, 3938 result); 3939 return 1; 3940 } 3941 3942 // update channels 3943 for (i = 0; i < num_channels; i++) { 3944 uint16_t remote_cid = little_endian_read_16(command, 8 + (i * sizeof(uint16_t))); 3945 l2cap_channel_t *channel = l2cap_get_channel_for_remote_handle_and_cid(handle, remote_cid); 3946 channel->remote_mps = new_mps; 3947 channel->remote_mtu = new_mtu; 3948 // emit event 3949 uint8_t event[8]; 3950 event[0] = L2CAP_EVENT_ECBM_RECONFIGURED; 3951 event[1] = sizeof(event) - 2; 3952 little_endian_store_16(event, 2, channel->local_cid); 3953 little_endian_store_16(event, 4, new_mtu); 3954 little_endian_store_16(event, 6, new_mps); 3955 l2cap_dispatch_to_channel(channel, HCI_EVENT_PACKET, event, sizeof(event)); 3956 } 3957 3958 // send accept 3959 l2cap_register_signaling_response(handle, L2CAP_CREDIT_BASED_RECONFIGURE_REQUEST, sig_id, signaling_cid, 0); 3960 return 1; 3961 3962 case L2CAP_CREDIT_BASED_RECONFIGURE_RESPONSE: 3963 // check size 3964 if (len < 2u) return 0u; 3965 3966 result = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET + 0); 3967 btstack_linked_list_iterator_init(&it, &l2cap_channels); 3968 while (btstack_linked_list_iterator_has_next(&it)) { 3969 l2cap_channel_t *channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 3970 if (!l2cap_is_dynamic_channel_type(channel->channel_type)) continue; 3971 if (channel->con_handle != handle) continue; 3972 if (channel->local_sig_id != sig_id) continue; 3973 if (channel->state != L2CAP_STATE_WAIT_ENHANCED_RENEGOTIATION_RESPONSE) continue; 3974 // complete request 3975 if (result == 0) { 3976 channel->receive_sdu_buffer = channel->renegotiate_sdu_buffer; 3977 channel->local_mtu = channel->renegotiate_mtu; 3978 } 3979 channel->state = L2CAP_STATE_OPEN; 3980 // emit event 3981 l2cap_ecbm_emit_reconfigure_complete(channel, result); 3982 } 3983 break; 3984 3985 default: 3986 btstack_unreachable(); 3987 break; 3988 } 3989 return 0; 3990 } 3991 3992 #endif 3993 3994 #ifdef ENABLE_BLE 3995 3996 static void l2cap_emit_connection_parameter_update_response(hci_con_handle_t con_handle, uint16_t result){ 3997 uint8_t event[6]; 3998 event[0] = L2CAP_EVENT_CONNECTION_PARAMETER_UPDATE_RESPONSE; 3999 event[1] = 4; 4000 little_endian_store_16(event, 2, con_handle); 4001 little_endian_store_16(event, 4, result); 4002 l2cap_emit_event(event, sizeof(event)); 4003 } 4004 4005 // @return valid 4006 static int l2cap_le_signaling_handler_dispatch(hci_con_handle_t handle, uint8_t * command, uint8_t sig_id){ 4007 hci_connection_t * connection; 4008 uint16_t result; 4009 uint8_t event[12]; 4010 4011 #ifdef L2CAP_USES_CREDIT_BASED_CHANNELS 4012 l2cap_channel_t * channel; 4013 btstack_linked_list_iterator_t it; 4014 #endif 4015 #ifdef ENABLE_L2CAP_LE_CREDIT_BASED_FLOW_CONTROL_MODE 4016 uint16_t local_cid; 4017 uint16_t le_psm; 4018 l2cap_service_t * service; 4019 uint16_t source_cid; 4020 #endif 4021 4022 uint8_t code = command[L2CAP_SIGNALING_COMMAND_CODE_OFFSET]; 4023 uint16_t len = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_LENGTH_OFFSET); 4024 log_info("le dispatch: command 0x%02x, sig id %u, len %u", code, sig_id, len); 4025 4026 switch (code){ 4027 4028 case CONNECTION_PARAMETER_UPDATE_REQUEST: 4029 // check size 4030 if (len < 8u) return 0u; 4031 connection = hci_connection_for_handle(handle); 4032 if (connection != NULL){ 4033 if (connection->role != HCI_ROLE_MASTER){ 4034 // reject command without notifying upper layer when not in master role 4035 return 0; 4036 } 4037 le_connection_parameter_range_t existing_range; 4038 gap_get_connection_parameter_range(&existing_range); 4039 uint16_t le_conn_interval_min = little_endian_read_16(command,L2CAP_SIGNALING_COMMAND_DATA_OFFSET); 4040 uint16_t le_conn_interval_max = little_endian_read_16(command,L2CAP_SIGNALING_COMMAND_DATA_OFFSET+2); 4041 uint16_t le_conn_latency = little_endian_read_16(command,L2CAP_SIGNALING_COMMAND_DATA_OFFSET+4); 4042 uint16_t le_supervision_timeout = little_endian_read_16(command,L2CAP_SIGNALING_COMMAND_DATA_OFFSET+6); 4043 4044 int update_parameter = gap_connection_parameter_range_included(&existing_range, le_conn_interval_min, le_conn_interval_max, le_conn_latency, le_supervision_timeout); 4045 if (update_parameter){ 4046 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_SEND_RESPONSE; 4047 connection->le_conn_interval_min = le_conn_interval_min; 4048 connection->le_conn_interval_max = le_conn_interval_max; 4049 connection->le_conn_latency = le_conn_latency; 4050 connection->le_supervision_timeout = le_supervision_timeout; 4051 } else { 4052 connection->le_con_parameter_update_state = CON_PARAMETER_UPDATE_DENY; 4053 } 4054 connection->le_con_param_update_identifier = sig_id; 4055 } 4056 4057 event[0] = L2CAP_EVENT_CONNECTION_PARAMETER_UPDATE_REQUEST; 4058 event[1] = 8; 4059 little_endian_store_16(event, 2, handle); 4060 (void)memcpy(&event[4], &command[4], 8); 4061 l2cap_emit_event(event, sizeof(event)); 4062 break; 4063 4064 case CONNECTION_PARAMETER_UPDATE_RESPONSE: 4065 // check size 4066 if (len < 2u) return 0u; 4067 result = little_endian_read_16(command, 4); 4068 l2cap_emit_connection_parameter_update_response(handle, result); 4069 break; 4070 4071 #ifdef ENABLE_L2CAP_ENHANCED_CREDIT_BASED_FLOW_CONTROL_MODE 4072 case L2CAP_CREDIT_BASED_CONNECTION_REQUEST: 4073 case L2CAP_CREDIT_BASED_CONNECTION_RESPONSE: 4074 case L2CAP_CREDIT_BASED_RECONFIGURE_REQUEST: 4075 case L2CAP_CREDIT_BASED_RECONFIGURE_RESPONSE: 4076 return l2cap_ecbm_signaling_handler_dispatch(handle, L2CAP_CID_SIGNALING_LE, command, sig_id); 4077 #endif 4078 4079 #ifdef L2CAP_USES_CREDIT_BASED_CHANNELS 4080 case COMMAND_REJECT: 4081 btstack_linked_list_iterator_init(&it, &l2cap_channels); 4082 while (btstack_linked_list_iterator_has_next(&it)){ 4083 channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 4084 if (!l2cap_is_dynamic_channel_type(channel->channel_type)) continue; 4085 if (channel->con_handle != handle) continue; 4086 if (channel->local_sig_id != sig_id) continue; 4087 #ifdef ENABLE_L2CAP_LE_CREDIT_BASED_FLOW_CONTROL_MODE 4088 // if received while waiting for le connection response, assume legacy device 4089 if (channel->state == L2CAP_STATE_WAIT_LE_CONNECTION_RESPONSE){ 4090 channel->state = L2CAP_STATE_CLOSED; 4091 // no official value for this, use: Connection refused – LE_PSM not supported 4092 l2cap_cbm_emit_channel_opened(channel, L2CAP_CBM_CONNECTION_RESULT_SPSM_NOT_SUPPORTED); 4093 4094 // discard channel 4095 btstack_linked_list_remove(&l2cap_channels, (btstack_linked_item_t *) channel); 4096 l2cap_free_channel_entry(channel); 4097 continue; 4098 } 4099 #endif 4100 #ifdef ENABLE_L2CAP_ENHANCED_CREDIT_BASED_FLOW_CONTROL_MODE 4101 // if received while waiting for le connection response, assume legacy device 4102 if (channel->state == L2CAP_STATE_WAIT_ENHANCED_CONNECTION_RESPONSE){ 4103 channel->state = L2CAP_STATE_CLOSED; 4104 // treat as SPSM not supported 4105 l2cap_ecbm_emit_channel_opened(channel, L2CAP_CONNECTION_RESPONSE_RESULT_REFUSED_PSM); 4106 4107 // discard channel 4108 btstack_linked_list_remove(&l2cap_channels, (btstack_linked_item_t *) channel); 4109 l2cap_free_channel_entry(channel); 4110 continue; 4111 } 4112 #endif 4113 } 4114 break; 4115 #endif 4116 4117 #ifdef ENABLE_L2CAP_LE_CREDIT_BASED_FLOW_CONTROL_MODE 4118 case LE_CREDIT_BASED_CONNECTION_REQUEST: 4119 // check size 4120 if (len < 10u) return 0u; 4121 4122 // get hci connection, bail if not found (must not happen) 4123 connection = hci_connection_for_handle(handle); 4124 if (!connection) return 0; 4125 4126 // check if service registered 4127 le_psm = little_endian_read_16(command, 4); 4128 service = l2cap_cbm_get_service(le_psm); 4129 source_cid = little_endian_read_16(command, 6); 4130 4131 if (service){ 4132 if (source_cid < 0x40u){ 4133 l2cap_register_signaling_response(handle, LE_CREDIT_BASED_CONNECTION_REQUEST, sig_id, source_cid, L2CAP_CBM_CONNECTION_RESULT_INVALID_SOURCE_CID); 4134 return 1; 4135 } 4136 4137 // go through list of channels for this ACL connection and check if we get a match 4138 btstack_linked_list_iterator_init(&it, &l2cap_channels); 4139 while (btstack_linked_list_iterator_has_next(&it)){ 4140 l2cap_channel_t * a_channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 4141 if (!l2cap_is_dynamic_channel_type(a_channel->channel_type)) continue; 4142 if (a_channel->con_handle != handle) continue; 4143 if (a_channel->remote_cid != source_cid) continue; 4144 l2cap_register_signaling_response(handle, LE_CREDIT_BASED_CONNECTION_REQUEST, sig_id, source_cid, L2CAP_CBM_CONNECTION_RESULT_SOURCE_CID_ALREADY_ALLOCATED); 4145 return 1; 4146 } 4147 4148 // security: check encryption 4149 if (service->required_security_level >= LEVEL_2){ 4150 if (gap_encryption_key_size(handle) == 0){ 4151 l2cap_register_signaling_response(handle, LE_CREDIT_BASED_CONNECTION_REQUEST, sig_id, source_cid, L2CAP_CBM_CONNECTION_RESULT_INSUFFICIENT_ENCRYPTION); 4152 return 1; 4153 } 4154 // anything less than 16 byte key size is insufficient 4155 if (gap_encryption_key_size(handle) < 16){ 4156 l2cap_register_signaling_response(handle, LE_CREDIT_BASED_CONNECTION_REQUEST, sig_id, source_cid, L2CAP_CBM_CONNECTION_RESULT_ENCYRPTION_KEY_SIZE_TOO_SHORT); 4157 return 1; 4158 } 4159 } 4160 4161 // security: check authentication 4162 if (service->required_security_level >= LEVEL_3){ 4163 if (!gap_authenticated(handle)){ 4164 l2cap_register_signaling_response(handle, LE_CREDIT_BASED_CONNECTION_REQUEST, sig_id, source_cid, L2CAP_CBM_CONNECTION_RESULT_INSUFFICIENT_AUTHENTICATION); 4165 return 1; 4166 } 4167 } 4168 4169 // security: check authorization 4170 if (service->required_security_level >= LEVEL_4){ 4171 if (gap_authorization_state(handle) != AUTHORIZATION_GRANTED){ 4172 l2cap_register_signaling_response(handle, LE_CREDIT_BASED_CONNECTION_REQUEST, sig_id, source_cid, L2CAP_CBM_CONNECTION_RESULT_INSUFFICIENT_AUTHORIZATION); 4173 return 1; 4174 } 4175 } 4176 4177 // allocate channel 4178 channel = l2cap_create_channel_entry(service->packet_handler, L2CAP_CHANNEL_TYPE_CHANNEL_CBM, connection->address, 4179 BD_ADDR_TYPE_LE_RANDOM, le_psm, service->mtu, service->required_security_level); 4180 if (!channel){ 4181 l2cap_register_signaling_response(handle, LE_CREDIT_BASED_CONNECTION_REQUEST, sig_id, source_cid, L2CAP_CBM_CONNECTION_RESULT_NO_RESOURCES_AVAILABLE); 4182 return 1; 4183 } 4184 4185 channel->con_handle = handle; 4186 channel->remote_cid = source_cid; 4187 channel->remote_sig_id = sig_id; 4188 channel->remote_mtu = little_endian_read_16(command, 8); 4189 channel->remote_mps = little_endian_read_16(command, 10); 4190 channel->credits_outgoing = little_endian_read_16(command, 12); 4191 4192 // set initial state 4193 channel->state = L2CAP_STATE_WAIT_CLIENT_ACCEPT_OR_REJECT; 4194 channel->state_var |= L2CAP_CHANNEL_STATE_VAR_INCOMING; 4195 4196 // add to connections list 4197 btstack_linked_list_add_tail(&l2cap_channels, (btstack_linked_item_t *) channel); 4198 4199 // post connection request event 4200 l2cap_cbm_emit_incoming_connection(channel); 4201 4202 } else { 4203 l2cap_register_signaling_response(handle, LE_CREDIT_BASED_CONNECTION_REQUEST, sig_id, source_cid, L2CAP_CBM_CONNECTION_RESULT_SPSM_NOT_SUPPORTED); 4204 } 4205 break; 4206 4207 case LE_CREDIT_BASED_CONNECTION_RESPONSE: 4208 // check size 4209 if (len < 10u) return 0u; 4210 4211 // Find channel for this sig_id and connection handle 4212 channel = NULL; 4213 btstack_linked_list_iterator_init(&it, &l2cap_channels); 4214 while (btstack_linked_list_iterator_has_next(&it)){ 4215 l2cap_channel_t * a_channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 4216 if (!l2cap_is_dynamic_channel_type(a_channel->channel_type)) continue; 4217 if (a_channel->con_handle != handle) continue; 4218 if (a_channel->local_sig_id != sig_id) continue; 4219 channel = a_channel; 4220 break; 4221 } 4222 if (!channel) break; 4223 4224 // cid + 0 4225 result = little_endian_read_16 (command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET+8); 4226 if (result){ 4227 channel->state = L2CAP_STATE_CLOSED; 4228 uint8_t status = l2cap_cbm_status_for_result(result); 4229 l2cap_cbm_emit_channel_opened(channel, status); 4230 4231 // discard channel 4232 btstack_linked_list_remove(&l2cap_channels, (btstack_linked_item_t *) channel); 4233 l2cap_free_channel_entry(channel); 4234 break; 4235 } 4236 4237 // success 4238 channel->remote_cid = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET + 0); 4239 channel->remote_mtu = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET + 2); 4240 channel->remote_mps = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET + 4); 4241 channel->credits_outgoing = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET + 6); 4242 channel->state = L2CAP_STATE_OPEN; 4243 l2cap_cbm_emit_channel_opened(channel, ERROR_CODE_SUCCESS); 4244 break; 4245 #endif 4246 4247 #ifdef L2CAP_USES_CREDIT_BASED_CHANNELS 4248 case L2CAP_FLOW_CONTROL_CREDIT_INDICATION: 4249 return l2cap_credit_based_handle_credit_indication(handle, command, len) ? 1 : 0; 4250 4251 case DISCONNECTION_REQUEST: 4252 4253 // check size 4254 if (len < 4u) return 0u; 4255 4256 // find channel 4257 local_cid = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET + 0); 4258 channel = l2cap_get_channel_for_local_cid_and_handle(local_cid, handle); 4259 if (!channel) { 4260 log_error("credit: no channel for cid 0x%02x", local_cid); 4261 break; 4262 } 4263 channel->remote_sig_id = sig_id; 4264 channel->state = L2CAP_STATE_WILL_SEND_DISCONNECT_RESPONSE; 4265 break; 4266 4267 case DISCONNECTION_RESPONSE: 4268 // check size 4269 if (len < 4u) return 0u; 4270 4271 // find channel 4272 local_cid = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET + 0); 4273 channel = l2cap_get_channel_for_local_cid_and_handle(local_cid, handle); 4274 if (!channel) break; 4275 if (channel->local_sig_id == sig_id) { 4276 if (channel->state == L2CAP_STATE_WAIT_DISCONNECT){ 4277 l2cap_finalize_channel_close(channel); 4278 } 4279 } 4280 break; 4281 #endif 4282 4283 default: 4284 // command unknown -> reject command 4285 return 0; 4286 } 4287 return 1; 4288 } 4289 #endif 4290 4291 #ifdef ENABLE_CLASSIC 4292 static void l2cap_acl_classic_handler_for_channel(l2cap_channel_t * l2cap_channel, uint8_t * packet, uint16_t size){ 4293 4294 // forward data only in OPEN state 4295 if (l2cap_channel->state != L2CAP_STATE_OPEN) return; 4296 4297 #ifdef L2CAP_USES_CREDIT_BASED_CHANNELS 4298 if (l2cap_channel->channel_type == L2CAP_CHANNEL_TYPE_CHANNEL_ECBM){ 4299 l2cap_credit_based_handle_pdu(l2cap_channel, packet, size); 4300 return; 4301 } 4302 #endif 4303 4304 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 4305 if (l2cap_channel->mode == L2CAP_CHANNEL_MODE_ENHANCED_RETRANSMISSION){ 4306 4307 int fcs_size = l2cap_channel->fcs_option ? 2 : 0; 4308 4309 // assert control + FCS fields are inside 4310 if (size < COMPLETE_L2CAP_HEADER+2+fcs_size) return; 4311 4312 if (l2cap_channel->fcs_option){ 4313 // verify FCS (required if one side requested it) 4314 uint16_t fcs_calculated = crc16_calc(&packet[4], size - (4+2)); 4315 uint16_t fcs_packet = little_endian_read_16(packet, size-2); 4316 4317 #ifdef L2CAP_ERTM_SIMULATE_FCS_ERROR_INTERVAL 4318 // simulate fcs error 4319 static int counter = 0; 4320 if (++counter == L2CAP_ERTM_SIMULATE_FCS_ERROR_INTERVAL) { 4321 log_info("Simulate fcs error"); 4322 fcs_calculated++; 4323 counter = 0; 4324 } 4325 #endif 4326 4327 if (fcs_calculated == fcs_packet){ 4328 log_info("Packet FCS 0x%04x verified", fcs_packet); 4329 } else { 4330 log_error("FCS mismatch! Packet 0x%04x, calculated 0x%04x", fcs_packet, fcs_calculated); 4331 // ERTM State Machine in Bluetooth Spec does not handle 'I-Frame with invalid FCS' 4332 return; 4333 } 4334 } 4335 4336 // switch on packet type 4337 uint16_t control = little_endian_read_16(packet, COMPLETE_L2CAP_HEADER); 4338 uint8_t req_seq = (control >> 8) & 0x3f; 4339 int final = (control >> 7) & 0x01; 4340 if (control & 1){ 4341 // S-Frame 4342 int poll = (control >> 4) & 0x01; 4343 l2cap_supervisory_function_t s = (l2cap_supervisory_function_t) ((control >> 2) & 0x03); 4344 log_info("Control: 0x%04x => Supervisory function %u, ReqSeq %02u", control, (int) s, req_seq); 4345 l2cap_ertm_tx_packet_state_t * tx_state; 4346 switch (s){ 4347 case L2CAP_SUPERVISORY_FUNCTION_RR_RECEIVER_READY: 4348 log_info("L2CAP_SUPERVISORY_FUNCTION_RR_RECEIVER_READY"); 4349 l2cap_ertm_process_req_seq(l2cap_channel, req_seq); 4350 if (poll && final){ 4351 // S-frames shall not be transmitted with both the F-bit and the P-bit set to 1 at the same time. 4352 log_error("P=F=1 in S-Frame"); 4353 break; 4354 } 4355 if (poll){ 4356 // check if we did request selective retransmission before <==> we have stored SDU segments 4357 int i; 4358 int num_stored_out_of_order_packets = 0; 4359 for (i=0;i<l2cap_channel->num_rx_buffers;i++){ 4360 int index = l2cap_channel->rx_store_index + i; 4361 if (index >= l2cap_channel->num_rx_buffers){ 4362 index -= l2cap_channel->num_rx_buffers; 4363 } 4364 l2cap_ertm_rx_packet_state_t * rx_state = &l2cap_channel->rx_packets_state[index]; 4365 if (!rx_state->valid) continue; 4366 num_stored_out_of_order_packets++; 4367 } 4368 if (num_stored_out_of_order_packets){ 4369 l2cap_channel->send_supervisor_frame_selective_reject = 1; 4370 } else { 4371 l2cap_channel->send_supervisor_frame_receiver_ready = 1; 4372 } 4373 l2cap_channel->set_final_bit_after_packet_with_poll_bit_set = 1; 4374 } 4375 if (final){ 4376 // Stop-MonitorTimer 4377 l2cap_ertm_stop_monitor_timer(l2cap_channel); 4378 // If UnackedFrames > 0 then Start-RetransTimer 4379 if (l2cap_channel->unacked_frames){ 4380 l2cap_ertm_start_retransmission_timer(l2cap_channel); 4381 } 4382 // final bit set <- response to RR with poll bit set. All not acknowledged packets need to be retransmitted 4383 l2cap_ertm_retransmit_unacknowleded_frames(l2cap_channel); 4384 } 4385 break; 4386 case L2CAP_SUPERVISORY_FUNCTION_REJ_REJECT: 4387 log_info("L2CAP_SUPERVISORY_FUNCTION_REJ_REJECT"); 4388 l2cap_ertm_process_req_seq(l2cap_channel, req_seq); 4389 // restart transmittion from last unacknowledted packet (earlier packets already freed in l2cap_ertm_process_req_seq) 4390 l2cap_ertm_retransmit_unacknowleded_frames(l2cap_channel); 4391 break; 4392 case L2CAP_SUPERVISORY_FUNCTION_RNR_RECEIVER_NOT_READY: 4393 log_error("L2CAP_SUPERVISORY_FUNCTION_RNR_RECEIVER_NOT_READY"); 4394 break; 4395 case L2CAP_SUPERVISORY_FUNCTION_SREJ_SELECTIVE_REJECT: 4396 log_info("L2CAP_SUPERVISORY_FUNCTION_SREJ_SELECTIVE_REJECT"); 4397 if (poll){ 4398 l2cap_ertm_process_req_seq(l2cap_channel, req_seq); 4399 } 4400 // find requested i-frame 4401 tx_state = l2cap_ertm_get_tx_state(l2cap_channel, req_seq); 4402 if (tx_state){ 4403 log_info("Retransmission for tx_seq %u requested", req_seq); 4404 l2cap_channel->set_final_bit_after_packet_with_poll_bit_set = poll; 4405 tx_state->retransmission_requested = 1; 4406 l2cap_channel->srej_active = 1; 4407 } 4408 break; 4409 default: 4410 break; 4411 } 4412 } else { 4413 // I-Frame 4414 // get control 4415 l2cap_segmentation_and_reassembly_t sar = (l2cap_segmentation_and_reassembly_t) (control >> 14); 4416 uint8_t tx_seq = (control >> 1) & 0x3f; 4417 log_info("Control: 0x%04x => SAR %u, ReqSeq %02u, R?, TxSeq %02u", control, (int) sar, req_seq, tx_seq); 4418 log_info("SAR: pos %u", l2cap_channel->reassembly_pos); 4419 log_info("State: expected_tx_seq %02u, req_seq %02u", l2cap_channel->expected_tx_seq, l2cap_channel->req_seq); 4420 l2cap_ertm_process_req_seq(l2cap_channel, req_seq); 4421 if (final){ 4422 // final bit set <- response to RR with poll bit set. All not acknowledged packets need to be retransmitted 4423 l2cap_ertm_retransmit_unacknowleded_frames(l2cap_channel); 4424 } 4425 4426 // get SDU 4427 const uint8_t * payload_data = &packet[COMPLETE_L2CAP_HEADER+2]; 4428 uint16_t payload_len = size-(COMPLETE_L2CAP_HEADER+2+fcs_size); 4429 4430 // assert SDU size is smaller or equal to our buffers 4431 uint16_t max_payload_size = 0; 4432 switch (sar){ 4433 case L2CAP_SEGMENTATION_AND_REASSEMBLY_UNSEGMENTED_L2CAP_SDU: 4434 case L2CAP_SEGMENTATION_AND_REASSEMBLY_START_OF_L2CAP_SDU: 4435 // SDU Length + MPS 4436 max_payload_size = l2cap_channel->local_mps + 2; 4437 break; 4438 case L2CAP_SEGMENTATION_AND_REASSEMBLY_CONTINUATION_OF_L2CAP_SDU: 4439 case L2CAP_SEGMENTATION_AND_REASSEMBLY_END_OF_L2CAP_SDU: 4440 max_payload_size = l2cap_channel->local_mps; 4441 break; 4442 default: 4443 btstack_assert(false); 4444 break; 4445 } 4446 if (payload_len > max_payload_size){ 4447 log_info("payload len %u > max payload %u -> drop packet", payload_len, max_payload_size); 4448 return; 4449 } 4450 4451 // check ordering 4452 if (l2cap_channel->expected_tx_seq == tx_seq){ 4453 log_info("Received expected frame with TxSeq == ExpectedTxSeq == %02u", tx_seq); 4454 l2cap_channel->expected_tx_seq = l2cap_next_ertm_seq_nr(l2cap_channel->expected_tx_seq); 4455 l2cap_channel->req_seq = l2cap_channel->expected_tx_seq; 4456 4457 // process SDU 4458 l2cap_ertm_handle_in_sequence_sdu(l2cap_channel, sar, payload_data, payload_len); 4459 4460 // process stored segments 4461 while (true){ 4462 int index = l2cap_channel->rx_store_index; 4463 l2cap_ertm_rx_packet_state_t * rx_state = &l2cap_channel->rx_packets_state[index]; 4464 if (!rx_state->valid) break; 4465 4466 log_info("Processing stored frame with TxSeq == ExpectedTxSeq == %02u", l2cap_channel->expected_tx_seq); 4467 l2cap_channel->expected_tx_seq = l2cap_next_ertm_seq_nr(l2cap_channel->expected_tx_seq); 4468 l2cap_channel->req_seq = l2cap_channel->expected_tx_seq; 4469 4470 rx_state->valid = 0; 4471 l2cap_ertm_handle_in_sequence_sdu(l2cap_channel, rx_state->sar, &l2cap_channel->rx_packets_data[index], rx_state->len); 4472 4473 // update rx store index 4474 index++; 4475 if (index >= l2cap_channel->num_rx_buffers){ 4476 index = 0; 4477 } 4478 l2cap_channel->rx_store_index = index; 4479 } 4480 4481 // 4482 l2cap_channel->send_supervisor_frame_receiver_ready = 1; 4483 4484 } else { 4485 int delta = (tx_seq - l2cap_channel->expected_tx_seq) & 0x3f; 4486 if (delta < 2){ 4487 // store segment 4488 l2cap_ertm_handle_out_of_sequence_sdu(l2cap_channel, sar, delta, payload_data, payload_len); 4489 4490 log_info("Received unexpected frame TxSeq %u but expected %u -> send S-SREJ", tx_seq, l2cap_channel->expected_tx_seq); 4491 l2cap_channel->send_supervisor_frame_selective_reject = 1; 4492 } else { 4493 log_info("Received unexpected frame TxSeq %u but expected %u -> send S-REJ", tx_seq, l2cap_channel->expected_tx_seq); 4494 l2cap_channel->send_supervisor_frame_reject = 1; 4495 } 4496 } 4497 } 4498 return; 4499 } 4500 #endif 4501 4502 // check size 4503 uint16_t payload_size = size - COMPLETE_L2CAP_HEADER; 4504 if (l2cap_channel->local_mtu < payload_size) return; 4505 4506 l2cap_dispatch_to_channel(l2cap_channel, L2CAP_DATA_PACKET, &packet[COMPLETE_L2CAP_HEADER], payload_size); 4507 } 4508 #endif 4509 4510 static void l2cap_acl_classic_handler(hci_con_handle_t handle, uint8_t *packet, uint16_t size){ 4511 #ifdef ENABLE_CLASSIC 4512 l2cap_channel_t * l2cap_channel; 4513 l2cap_fixed_channel_t * l2cap_fixed_channel; 4514 4515 uint16_t channel_id = READ_L2CAP_CHANNEL_ID(packet); 4516 uint8_t broadcast_flag = READ_ACL_FLAGS(packet) >> 2; 4517 switch (channel_id) { 4518 4519 case L2CAP_CID_SIGNALING: { 4520 if (broadcast_flag != 0) break; 4521 uint32_t command_offset = 8; 4522 while ((command_offset + L2CAP_SIGNALING_COMMAND_DATA_OFFSET) < size) { 4523 // assert signaling command is fully inside packet 4524 uint16_t data_len = little_endian_read_16(packet, command_offset + L2CAP_SIGNALING_COMMAND_LENGTH_OFFSET); 4525 uint32_t next_command_offset = command_offset + L2CAP_SIGNALING_COMMAND_DATA_OFFSET + data_len; 4526 if (next_command_offset > size){ 4527 log_error("l2cap signaling command len invalid -> drop"); 4528 break; 4529 } 4530 // handle signaling command 4531 l2cap_signaling_handler_dispatch(handle, &packet[command_offset]); 4532 // go to next command 4533 command_offset = next_command_offset; 4534 } 4535 break; 4536 } 4537 4538 case L2CAP_CID_CONNECTIONLESS_CHANNEL: 4539 if (broadcast_flag == 0) break; 4540 l2cap_fixed_channel = l2cap_fixed_channel_for_channel_id(L2CAP_CID_CONNECTIONLESS_CHANNEL); 4541 if (!l2cap_fixed_channel) break; 4542 if (!l2cap_fixed_channel->packet_handler) break; 4543 (*l2cap_fixed_channel->packet_handler)(UCD_DATA_PACKET, handle, &packet[COMPLETE_L2CAP_HEADER], size-COMPLETE_L2CAP_HEADER); 4544 break; 4545 4546 #ifdef ENABLE_BLE 4547 case L2CAP_CID_BR_EDR_SECURITY_MANAGER: 4548 l2cap_fixed_channel = l2cap_fixed_channel_for_channel_id(L2CAP_CID_SECURITY_MANAGER_PROTOCOL); 4549 if ((l2cap_fixed_channel == NULL) || (l2cap_fixed_channel->packet_handler == NULL)){ 4550 // Pairing Failed 4551 l2cap_register_signaling_response(handle, (uint8_t) SM_PAIRING_FAILED, 0, L2CAP_CID_BR_EDR_SECURITY_MANAGER, SM_REASON_PAIRING_NOT_SUPPORTED); 4552 } else { 4553 (*l2cap_fixed_channel->packet_handler)(SM_DATA_PACKET, handle, &packet[COMPLETE_L2CAP_HEADER], size-COMPLETE_L2CAP_HEADER); 4554 } 4555 break; 4556 #endif 4557 4558 default: 4559 if (broadcast_flag != 0) break; 4560 // Find channel for this channel_id and connection handle 4561 l2cap_channel = l2cap_get_channel_for_local_cid_and_handle(channel_id, handle); 4562 if (l2cap_channel != NULL){ 4563 l2cap_acl_classic_handler_for_channel(l2cap_channel, packet, size); 4564 } 4565 break; 4566 } 4567 #else 4568 UNUSED(handle); // ok: no code 4569 UNUSED(packet); // ok: no code 4570 UNUSED(size); // ok: no code 4571 #endif 4572 } 4573 4574 static void l2cap_acl_le_handler(hci_con_handle_t handle, uint8_t *packet, uint16_t size){ 4575 #ifdef ENABLE_BLE 4576 4577 l2cap_fixed_channel_t * l2cap_fixed_channel; 4578 4579 #ifdef ENABLE_L2CAP_LE_CREDIT_BASED_FLOW_CONTROL_MODE 4580 l2cap_channel_t * l2cap_channel; 4581 #endif 4582 uint16_t channel_id = READ_L2CAP_CHANNEL_ID(packet); 4583 switch (channel_id) { 4584 4585 case L2CAP_CID_SIGNALING_LE: { 4586 uint16_t sig_id = packet[COMPLETE_L2CAP_HEADER + 1]; 4587 uint16_t len = little_endian_read_16(packet, COMPLETE_L2CAP_HEADER + 2); 4588 if ((COMPLETE_L2CAP_HEADER + 4u + len) > size) break; 4589 int valid = l2cap_le_signaling_handler_dispatch(handle, &packet[COMPLETE_L2CAP_HEADER], sig_id); 4590 if (!valid){ 4591 l2cap_register_signaling_response(handle, COMMAND_REJECT_LE, sig_id, 0, L2CAP_REJ_CMD_UNKNOWN); 4592 } 4593 break; 4594 } 4595 4596 case L2CAP_CID_ATTRIBUTE_PROTOCOL: 4597 l2cap_fixed_channel = l2cap_fixed_channel_for_channel_id(L2CAP_CID_ATTRIBUTE_PROTOCOL); 4598 if (!l2cap_fixed_channel) break; 4599 if (!l2cap_fixed_channel->packet_handler) break; 4600 (*l2cap_fixed_channel->packet_handler)(ATT_DATA_PACKET, handle, &packet[COMPLETE_L2CAP_HEADER], size-COMPLETE_L2CAP_HEADER); 4601 break; 4602 4603 case L2CAP_CID_SECURITY_MANAGER_PROTOCOL: 4604 l2cap_fixed_channel = l2cap_fixed_channel_for_channel_id(L2CAP_CID_SECURITY_MANAGER_PROTOCOL); 4605 if ((l2cap_fixed_channel == NULL) || (l2cap_fixed_channel->packet_handler == NULL)){ 4606 // Pairing Failed 4607 l2cap_register_signaling_response(handle, (uint8_t) SM_PAIRING_FAILED, 0, L2CAP_CID_SECURITY_MANAGER_PROTOCOL, SM_REASON_PAIRING_NOT_SUPPORTED); 4608 } else { 4609 (*l2cap_fixed_channel->packet_handler)(SM_DATA_PACKET, handle, &packet[COMPLETE_L2CAP_HEADER], size-COMPLETE_L2CAP_HEADER); 4610 } 4611 break; 4612 4613 default: 4614 4615 #ifdef ENABLE_L2CAP_LE_CREDIT_BASED_FLOW_CONTROL_MODE 4616 l2cap_channel = l2cap_get_channel_for_local_cid_and_handle(channel_id, handle); 4617 if (l2cap_channel != NULL) { 4618 l2cap_credit_based_handle_pdu(l2cap_channel, packet, size); 4619 } 4620 #endif 4621 break; 4622 } 4623 #else 4624 UNUSED(handle); // ok: no code 4625 UNUSED(packet); // ok: no code 4626 UNUSED(size); // ok: no code 4627 #endif 4628 } 4629 4630 static void l2cap_acl_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 4631 UNUSED(packet_type); // ok: registered with hci_register_acl_packet_handler 4632 UNUSED(channel); // ok: there is no channel 4633 4634 // Assert full L2CAP header present 4635 if (size < COMPLETE_L2CAP_HEADER) return; 4636 4637 // Dispatch to Classic or LE handler (SCO packets are not dispatched to L2CAP) 4638 hci_con_handle_t handle = READ_ACL_CONNECTION_HANDLE(packet); 4639 hci_connection_t *conn = hci_connection_for_handle(handle); 4640 if (!conn) return; 4641 if (conn->address_type == BD_ADDR_TYPE_ACL){ 4642 l2cap_acl_classic_handler(handle, packet, size); 4643 } else { 4644 l2cap_acl_le_handler(handle, packet, size); 4645 } 4646 4647 l2cap_run(); 4648 } 4649 4650 // Bluetooth 4.0 - allows to register handler for Attribute Protocol and Security Manager Protocol 4651 void l2cap_register_fixed_channel(btstack_packet_handler_t packet_handler, uint16_t channel_id) { 4652 l2cap_fixed_channel_t * channel = l2cap_fixed_channel_for_channel_id(channel_id); 4653 if (!channel) return; 4654 channel->packet_handler = packet_handler; 4655 } 4656 4657 #ifdef L2CAP_USES_CHANNELS 4658 // finalize closed channel - l2cap_handle_disconnect_request & DISCONNECTION_RESPONSE 4659 void l2cap_finalize_channel_close(l2cap_channel_t * channel){ 4660 channel->state = L2CAP_STATE_CLOSED; 4661 l2cap_handle_channel_closed(channel); 4662 // discard channel 4663 btstack_linked_list_remove(&l2cap_channels, (btstack_linked_item_t *) channel); 4664 l2cap_free_channel_entry(channel); 4665 } 4666 #endif 4667 4668 #ifdef ENABLE_CLASSIC 4669 static inline l2cap_service_t * l2cap_get_service(uint16_t psm){ 4670 return l2cap_get_service_internal(&l2cap_services, psm); 4671 } 4672 4673 static void l2cap_update_minimal_security_level(void){ 4674 // update minimal service security level 4675 gap_security_level_t minimal_level = LEVEL_1; 4676 btstack_linked_list_iterator_t it; 4677 btstack_linked_list_iterator_init(&it, &l2cap_services); 4678 while (btstack_linked_list_iterator_has_next(&it)){ 4679 l2cap_service_t * service = (l2cap_service_t *) btstack_linked_list_iterator_next(&it); 4680 if (service->required_security_level > minimal_level){ 4681 minimal_level = service->required_security_level; 4682 }; 4683 } 4684 gap_set_minimal_service_security_level(minimal_level); 4685 } 4686 4687 uint8_t l2cap_register_service(btstack_packet_handler_t service_packet_handler, uint16_t psm, uint16_t mtu, gap_security_level_t security_level){ 4688 4689 log_info("L2CAP_REGISTER_SERVICE psm 0x%x mtu %u", psm, mtu); 4690 4691 // check for alread registered psm 4692 l2cap_service_t *service = l2cap_get_service(psm); 4693 if (service) { 4694 log_error("register: PSM %u already registered", psm); 4695 return L2CAP_SERVICE_ALREADY_REGISTERED; 4696 } 4697 4698 // alloc structure 4699 service = btstack_memory_l2cap_service_get(); 4700 if (!service) { 4701 log_error("register: no memory for l2cap_service_t"); 4702 return BTSTACK_MEMORY_ALLOC_FAILED; 4703 } 4704 4705 // fill in 4706 service->psm = psm; 4707 service->mtu = mtu; 4708 service->packet_handler = service_packet_handler; 4709 service->required_security_level = security_level; 4710 4711 // add to services list 4712 btstack_linked_list_add(&l2cap_services, (btstack_linked_item_t *) service); 4713 4714 l2cap_update_minimal_security_level(); 4715 4716 #ifndef ENABLE_EXPLICIT_CONNECTABLE_MODE_CONTROL 4717 // enable page scan 4718 gap_connectable_control(1); 4719 #endif 4720 4721 4722 return ERROR_CODE_SUCCESS; 4723 } 4724 4725 uint8_t l2cap_unregister_service(uint16_t psm){ 4726 4727 log_info("unregister psm 0x%x", psm); 4728 4729 l2cap_service_t *service = l2cap_get_service(psm); 4730 if (!service) return L2CAP_SERVICE_DOES_NOT_EXIST; 4731 btstack_linked_list_remove(&l2cap_services, (btstack_linked_item_t *) service); 4732 btstack_memory_l2cap_service_free(service); 4733 4734 l2cap_update_minimal_security_level(); 4735 4736 #ifndef ENABLE_EXPLICIT_CONNECTABLE_MODE_CONTROL 4737 // disable page scan when no services registered 4738 if (btstack_linked_list_empty(&l2cap_services)) { 4739 gap_connectable_control(0); 4740 } 4741 #endif 4742 4743 return ERROR_CODE_SUCCESS; 4744 } 4745 #endif 4746 4747 4748 #ifdef L2CAP_USES_CREDIT_BASED_CHANNELS 4749 4750 static void l2cap_credit_based_send_pdu(l2cap_channel_t *channel) { 4751 btstack_assert(channel != NULL); 4752 btstack_assert(channel->send_sdu_buffer != NULL); 4753 btstack_assert(channel->credits_outgoing > 0); 4754 4755 // send part of SDU 4756 hci_reserve_packet_buffer(); 4757 uint8_t *acl_buffer = hci_get_outgoing_packet_buffer(); 4758 uint8_t *l2cap_payload = acl_buffer + 8; 4759 uint16_t pos = 0; 4760 if (!channel->send_sdu_pos) { 4761 // store SDU len 4762 channel->send_sdu_pos += 2u; 4763 little_endian_store_16(l2cap_payload, pos, channel->send_sdu_len); 4764 pos += 2u; 4765 } 4766 uint16_t payload_size = btstack_min(channel->send_sdu_len + 2u - channel->send_sdu_pos, channel->remote_mps - pos); 4767 log_info("len %u, pos %u => payload %u, credits %u", channel->send_sdu_len, channel->send_sdu_pos, payload_size, 4768 channel->credits_outgoing); 4769 (void) memcpy(&l2cap_payload[pos], 4770 &channel->send_sdu_buffer[channel->send_sdu_pos - 2u], 4771 payload_size); // -2 for virtual SDU len 4772 pos += payload_size; 4773 channel->send_sdu_pos += payload_size; 4774 l2cap_setup_header(acl_buffer, channel->con_handle, 0, channel->remote_cid, pos); 4775 4776 channel->credits_outgoing--; 4777 4778 // update state (mark SDU as done) before calling hci_send_acl_packet_buffer (trigger l2cap_le_send_pdu again) 4779 bool done = channel->send_sdu_pos >= (channel->send_sdu_len + 2u); 4780 if (done) { 4781 channel->send_sdu_buffer = NULL; 4782 } 4783 4784 hci_send_acl_packet_buffer(8u + pos); 4785 4786 if (done) { 4787 // send done event 4788 l2cap_emit_simple_event_with_cid(channel, L2CAP_EVENT_CBM_PACKET_SENT); 4789 // inform about can send now 4790 l2cap_cbm_notify_channel_can_send(channel); 4791 } 4792 } 4793 4794 static uint8_t l2cap_credit_based_send_data(uint16_t local_cid, const uint8_t * data, uint16_t size){ 4795 4796 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 4797 if (!channel) { 4798 log_error("l2cap send, no channel for cid 0x%02x", local_cid); 4799 return L2CAP_LOCAL_CID_DOES_NOT_EXIST; 4800 } 4801 4802 if (size > channel->remote_mtu){ 4803 log_error("l2cap send, cid 0x%02x, data length exceeds remote MTU.", local_cid); 4804 return L2CAP_DATA_LEN_EXCEEDS_REMOTE_MTU; 4805 } 4806 4807 if (channel->send_sdu_buffer){ 4808 log_info("l2cap send, cid 0x%02x, cannot send", local_cid); 4809 return BTSTACK_ACL_BUFFERS_FULL; 4810 } 4811 4812 channel->send_sdu_buffer = data; 4813 channel->send_sdu_len = size; 4814 channel->send_sdu_pos = 0; 4815 4816 l2cap_notify_channel_can_send(); 4817 return ERROR_CODE_SUCCESS; 4818 } 4819 4820 static uint8_t l2cap_credit_based_provide_credits(uint16_t local_cid, uint16_t credits){ 4821 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 4822 if (!channel) { 4823 log_error("le credits no channel for cid 0x%02x", local_cid); 4824 return L2CAP_LOCAL_CID_DOES_NOT_EXIST; 4825 } 4826 4827 // check state 4828 if (channel->state != L2CAP_STATE_OPEN){ 4829 log_error("le credits but channel 0x%02x not open yet", local_cid); 4830 } 4831 4832 // ignore if set to automatic credits 4833 if (channel->automatic_credits) return ERROR_CODE_SUCCESS; 4834 4835 // assert incoming credits + credits <= 0xffff 4836 uint32_t total_credits = channel->credits_incoming; 4837 total_credits += channel->new_credits_incoming; 4838 total_credits += credits; 4839 if (total_credits > 0xffffu){ 4840 log_error("le credits overrun: current %u, scheduled %u, additional %u", channel->credits_incoming, 4841 channel->new_credits_incoming, credits); 4842 } 4843 4844 // set credits_granted 4845 channel->new_credits_incoming += credits; 4846 4847 // go 4848 l2cap_run(); 4849 return ERROR_CODE_SUCCESS; 4850 } 4851 4852 static void l2cap_credit_based_send_credits(l2cap_channel_t *channel) { 4853 log_info("l2cap: sending %u credits", channel->new_credits_incoming); 4854 channel->local_sig_id = l2cap_next_sig_id(); 4855 uint16_t new_credits = channel->new_credits_incoming; 4856 channel->new_credits_incoming = 0; 4857 channel->credits_incoming += new_credits; 4858 uint16_t signaling_cid = channel->address_type == BD_ADDR_TYPE_ACL ? L2CAP_CID_SIGNALING : L2CAP_CID_SIGNALING_LE; 4859 l2cap_send_general_signaling_packet(channel->con_handle, signaling_cid, L2CAP_FLOW_CONTROL_CREDIT_INDICATION, channel->local_sig_id, channel->local_cid, new_credits); 4860 } 4861 4862 // @return valid 4863 static bool l2cap_credit_based_handle_credit_indication(hci_con_handle_t handle, const uint8_t * command, uint16_t len){ 4864 // check size 4865 if (len < 4u) return false; 4866 4867 // find channel 4868 uint16_t remote_cid = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET + 0); 4869 l2cap_channel_t * channel = l2cap_get_channel_for_remote_handle_and_cid(handle, remote_cid); 4870 if (!channel) { 4871 log_error("credit: no channel for handle 0x%04x/cid 0x%02x", handle, remote_cid); 4872 return true; 4873 } 4874 uint16_t new_credits = little_endian_read_16(command, L2CAP_SIGNALING_COMMAND_DATA_OFFSET + 2); 4875 uint16_t credits_before = channel->credits_outgoing; 4876 channel->credits_outgoing += new_credits; 4877 // check for credit overrun 4878 if (credits_before > channel->credits_outgoing) { 4879 log_error("credit: new credits caused overrrun for cid 0x%02x, disconnecting", channel->local_cid); 4880 channel->state = L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST; 4881 return true; 4882 } 4883 log_info("credit: %u credits for 0x%02x, now %u", new_credits, channel->local_cid, channel->credits_outgoing); 4884 l2cap_call_notify_channel_in_run = true; 4885 return true; 4886 } 4887 4888 static void l2cap_credit_based_handle_pdu(l2cap_channel_t * l2cap_channel, const uint8_t * packet, uint16_t size){ 4889 // ignore empty packets 4890 if (size == COMPLETE_L2CAP_HEADER) return; 4891 4892 // credit counting 4893 if (l2cap_channel->credits_incoming == 0u){ 4894 log_info("(e)CBM: packet received but no incoming credits"); 4895 l2cap_channel->state = L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST; 4896 return; 4897 } 4898 l2cap_channel->credits_incoming--; 4899 4900 // automatic credits 4901 if ((l2cap_channel->credits_incoming < L2CAP_CREDIT_BASED_FLOW_CONTROL_MODE_AUTOMATIC_CREDITS_WATERMARK) && l2cap_channel->automatic_credits){ 4902 l2cap_channel->new_credits_incoming = L2CAP_CREDIT_BASED_FLOW_CONTROL_MODE_AUTOMATIC_CREDITS_INCREMENT; 4903 } 4904 4905 // first fragment 4906 uint16_t pos = 0; 4907 if (!l2cap_channel->receive_sdu_len){ 4908 if (size < (COMPLETE_L2CAP_HEADER + 2)) return; 4909 uint16_t sdu_len = little_endian_read_16(packet, COMPLETE_L2CAP_HEADER); 4910 if(sdu_len > l2cap_channel->local_mtu) return; // SDU would be larger than our buffer 4911 l2cap_channel->receive_sdu_len = sdu_len; 4912 l2cap_channel->receive_sdu_pos = 0; 4913 pos += 2u; 4914 size -= 2u; 4915 } 4916 uint16_t fragment_size = size-COMPLETE_L2CAP_HEADER; 4917 uint16_t remaining_space = l2cap_channel->local_mtu - l2cap_channel->receive_sdu_pos; 4918 if (fragment_size > remaining_space) return; // SDU would cause buffer overrun 4919 (void)memcpy(&l2cap_channel->receive_sdu_buffer[l2cap_channel->receive_sdu_pos], 4920 &packet[COMPLETE_L2CAP_HEADER + pos], 4921 fragment_size); 4922 l2cap_channel->receive_sdu_pos += size - COMPLETE_L2CAP_HEADER; 4923 // done? 4924 log_debug("le packet pos %u, len %u", l2cap_channel->receive_sdu_pos, l2cap_channel->receive_sdu_len); 4925 if (l2cap_channel->receive_sdu_pos >= l2cap_channel->receive_sdu_len){ 4926 l2cap_dispatch_to_channel(l2cap_channel, L2CAP_DATA_PACKET, l2cap_channel->receive_sdu_buffer, l2cap_channel->receive_sdu_len); 4927 l2cap_channel->receive_sdu_len = 0; 4928 } 4929 } 4930 4931 static uint8_t l2cap_credit_based_disconnect(uint16_t local_cid){ 4932 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 4933 if (!channel) { 4934 return L2CAP_LOCAL_CID_DOES_NOT_EXIST; 4935 } 4936 channel->state = L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST; 4937 l2cap_run(); 4938 return ERROR_CODE_SUCCESS; 4939 } 4940 #endif 4941 4942 #ifdef ENABLE_L2CAP_LE_CREDIT_BASED_FLOW_CONTROL_MODE 4943 4944 static void l2cap_cbm_notify_channel_can_send(l2cap_channel_t *channel){ 4945 if (!channel->waiting_for_can_send_now) return; 4946 if (channel->send_sdu_buffer) return; 4947 channel->waiting_for_can_send_now = 0; 4948 log_debug("le can send now, local_cid 0x%x", channel->local_cid); 4949 l2cap_emit_simple_event_with_cid(channel, L2CAP_EVENT_CBM_CAN_SEND_NOW); 4950 } 4951 4952 // 1BH2222 4953 static void l2cap_cbm_emit_incoming_connection(l2cap_channel_t *channel) { 4954 log_info("le incoming addr_type %u, addr %s handle 0x%x psm 0x%x local_cid 0x%x remote_cid 0x%x, remote_mtu %u", 4955 channel->address_type, bd_addr_to_str(channel->address), channel->con_handle, channel->psm, channel->local_cid, channel->remote_cid, channel->remote_mtu); 4956 uint8_t event[19]; 4957 event[0] = L2CAP_EVENT_CBM_INCOMING_CONNECTION; 4958 event[1] = sizeof(event) - 2u; 4959 event[2] = channel->address_type; 4960 reverse_bd_addr(channel->address, &event[3]); 4961 little_endian_store_16(event, 9, channel->con_handle); 4962 little_endian_store_16(event, 11, channel->psm); 4963 little_endian_store_16(event, 13, channel->local_cid); 4964 little_endian_store_16(event, 15, channel->remote_cid); 4965 little_endian_store_16(event, 17, channel->remote_mtu); 4966 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 4967 l2cap_dispatch_to_channel(channel, HCI_EVENT_PACKET, event, sizeof(event)); 4968 } 4969 // 11BH22222 4970 static void l2cap_cbm_emit_channel_opened(l2cap_channel_t *channel, uint8_t status) { 4971 log_info("opened le channel status 0x%x addr_type %u addr %s handle 0x%x psm 0x%x local_cid 0x%x remote_cid 0x%x local_mtu %u, remote_mtu %u", 4972 status, channel->address_type, bd_addr_to_str(channel->address), channel->con_handle, channel->psm, 4973 channel->local_cid, channel->remote_cid, channel->local_mtu, channel->remote_mtu); 4974 uint8_t event[23]; 4975 event[0] = L2CAP_EVENT_CBM_CHANNEL_OPENED; 4976 event[1] = sizeof(event) - 2u; 4977 event[2] = status; 4978 event[3] = channel->address_type; 4979 reverse_bd_addr(channel->address, &event[4]); 4980 little_endian_store_16(event, 10, channel->con_handle); 4981 event[12] = (channel->state_var & L2CAP_CHANNEL_STATE_VAR_INCOMING) ? 1 : 0; 4982 little_endian_store_16(event, 13, channel->psm); 4983 little_endian_store_16(event, 15, channel->local_cid); 4984 little_endian_store_16(event, 17, channel->remote_cid); 4985 little_endian_store_16(event, 19, channel->local_mtu); 4986 little_endian_store_16(event, 21, channel->remote_mtu); 4987 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 4988 l2cap_dispatch_to_channel(channel, HCI_EVENT_PACKET, event, sizeof(event)); 4989 } 4990 // 2 4991 static void l2cap_cbm_emit_channel_closed(l2cap_channel_t * channel){ 4992 log_info("closed local_cid 0x%x", channel->local_cid); 4993 uint8_t event[4]; 4994 event[0] = L2CAP_EVENT_CBM_CHANNEL_CLOSED; 4995 event[1] = sizeof(event) - 2u; 4996 little_endian_store_16(event, 2, channel->local_cid); 4997 hci_dump_packet( HCI_EVENT_PACKET, 0, event, sizeof(event)); 4998 l2cap_dispatch_to_channel(channel, HCI_EVENT_PACKET, event, sizeof(event)); 4999 } 5000 5001 // finalize closed channel - l2cap_handle_disconnect_request & DISCONNECTION_RESPONSE 5002 void l2cap_cbm_finialize_channel_close(l2cap_channel_t * channel){ 5003 channel->state = L2CAP_STATE_CLOSED; 5004 l2cap_emit_simple_event_with_cid(channel, L2CAP_EVENT_CHANNEL_CLOSED); 5005 // discard channel 5006 btstack_linked_list_remove(&l2cap_channels, (btstack_linked_item_t *) channel); 5007 l2cap_free_channel_entry(channel); 5008 } 5009 5010 static inline l2cap_service_t * l2cap_cbm_get_service(uint16_t le_psm){ 5011 return l2cap_get_service_internal(&l2cap_le_services, le_psm); 5012 } 5013 5014 uint8_t l2cap_cbm_register_service(btstack_packet_handler_t packet_handler, uint16_t psm, gap_security_level_t security_level){ 5015 5016 log_info("l2cap_cbm_register_service psm 0x%x", psm); 5017 5018 // check for alread registered psm 5019 l2cap_service_t *service = l2cap_cbm_get_service(psm); 5020 if (service) { 5021 return L2CAP_SERVICE_ALREADY_REGISTERED; 5022 } 5023 5024 // alloc structure 5025 service = btstack_memory_l2cap_service_get(); 5026 if (!service) { 5027 log_error("register: no memory for l2cap_service_t"); 5028 return BTSTACK_MEMORY_ALLOC_FAILED; 5029 } 5030 5031 // fill in 5032 service->psm = psm; 5033 service->mtu = 0; 5034 service->packet_handler = packet_handler; 5035 service->required_security_level = security_level; 5036 5037 // add to services list 5038 btstack_linked_list_add(&l2cap_le_services, (btstack_linked_item_t *) service); 5039 5040 // done 5041 return ERROR_CODE_SUCCESS; 5042 } 5043 5044 uint8_t l2cap_cbm_unregister_service(uint16_t psm) { 5045 log_info("l2cap_cbm_unregister_service psm 0x%x", psm); 5046 l2cap_service_t *service = l2cap_cbm_get_service(psm); 5047 if (!service) return L2CAP_SERVICE_DOES_NOT_EXIST; 5048 5049 btstack_linked_list_remove(&l2cap_le_services, (btstack_linked_item_t *) service); 5050 btstack_memory_l2cap_service_free(service); 5051 return ERROR_CODE_SUCCESS; 5052 } 5053 5054 uint8_t l2cap_cbm_accept_connection(uint16_t local_cid, uint8_t * receive_sdu_buffer, uint16_t mtu, uint16_t initial_credits){ 5055 // get channel 5056 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 5057 if (!channel) return L2CAP_LOCAL_CID_DOES_NOT_EXIST; 5058 5059 // validate state 5060 if (channel->state != L2CAP_STATE_WAIT_CLIENT_ACCEPT_OR_REJECT){ 5061 return ERROR_CODE_COMMAND_DISALLOWED; 5062 } 5063 5064 // set state accept connection 5065 channel->state = L2CAP_STATE_WILL_SEND_LE_CONNECTION_RESPONSE_ACCEPT; 5066 channel->receive_sdu_buffer = receive_sdu_buffer; 5067 channel->local_mtu = mtu; 5068 channel->new_credits_incoming = initial_credits; 5069 channel->automatic_credits = initial_credits == L2CAP_LE_AUTOMATIC_CREDITS; 5070 5071 // go 5072 l2cap_run(); 5073 return ERROR_CODE_SUCCESS; 5074 } 5075 5076 uint8_t l2cap_cbm_decline_connection(uint16_t local_cid, uint16_t result) { 5077 // get channel 5078 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 5079 if (!channel) return L2CAP_LOCAL_CID_DOES_NOT_EXIST; 5080 5081 // validate state 5082 if (channel->state != L2CAP_STATE_WAIT_CLIENT_ACCEPT_OR_REJECT){ 5083 return ERROR_CODE_COMMAND_DISALLOWED; 5084 } 5085 5086 // set state decline connection 5087 channel->state = L2CAP_STATE_WILL_SEND_LE_CONNECTION_RESPONSE_DECLINE; 5088 channel->reason = L2CAP_CBM_CONNECTION_RESULT_NO_RESOURCES_AVAILABLE; 5089 l2cap_run(); 5090 return ERROR_CODE_SUCCESS; 5091 } 5092 5093 static gap_security_level_t l2cap_cbm_security_level_for_connection(hci_con_handle_t con_handle){ 5094 uint8_t encryption_key_size = gap_encryption_key_size(con_handle); 5095 if (encryption_key_size == 0) return LEVEL_0; 5096 5097 uint8_t authenticated = gap_authenticated(con_handle); 5098 if (!authenticated) return LEVEL_2; 5099 5100 return encryption_key_size == 16 ? LEVEL_4 : LEVEL_3; 5101 } 5102 5103 // used to handle pairing complete after triggering to increase 5104 static void l2cap_cbm_sm_packet_handler(uint8_t packet_type, uint16_t channel_nr, uint8_t *packet, uint16_t size) { 5105 UNUSED(channel_nr); 5106 UNUSED(size); 5107 UNUSED(packet_type); 5108 btstack_assert(packet_type == HCI_EVENT_PACKET); 5109 if (hci_event_packet_get_type(packet) != SM_EVENT_PAIRING_COMPLETE) return; 5110 hci_con_handle_t con_handle = sm_event_pairing_complete_get_handle(packet); 5111 btstack_linked_list_iterator_t it; 5112 btstack_linked_list_iterator_init(&it, &l2cap_channels); 5113 while (btstack_linked_list_iterator_has_next(&it)) { 5114 l2cap_channel_t *channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 5115 if (!l2cap_is_dynamic_channel_type(channel->channel_type)) continue; 5116 if (channel->con_handle != con_handle) continue; 5117 if (channel->state != L2CAP_STATE_WAIT_OUTGOING_SECURITY_LEVEL_UPDATE) continue; 5118 5119 // found channel, check security level 5120 if (l2cap_cbm_security_level_for_connection(con_handle) < channel->required_security_level){ 5121 // pairing failed or wasn't good enough, inform user 5122 l2cap_cbm_emit_channel_opened(channel, ERROR_CODE_INSUFFICIENT_SECURITY); 5123 // discard channel 5124 btstack_linked_list_remove(&l2cap_channels, (btstack_linked_item_t *) channel); 5125 l2cap_free_channel_entry(channel); 5126 } else { 5127 // send conn request now 5128 channel->state = L2CAP_STATE_WILL_SEND_LE_CONNECTION_REQUEST; 5129 l2cap_run(); 5130 } 5131 } 5132 } 5133 5134 uint8_t l2cap_cbm_create_channel(btstack_packet_handler_t packet_handler, hci_con_handle_t con_handle, 5135 uint16_t psm, uint8_t * receive_sdu_buffer, uint16_t mtu, uint16_t initial_credits, gap_security_level_t security_level, 5136 uint16_t * out_local_cid) { 5137 5138 static btstack_packet_callback_registration_t sm_event_callback_registration; 5139 static bool sm_callback_registered = false; 5140 5141 log_info("create, handle 0x%04x psm 0x%x mtu %u", con_handle, psm, mtu); 5142 5143 hci_connection_t * connection = hci_connection_for_handle(con_handle); 5144 if (!connection) { 5145 log_error("no hci_connection for handle 0x%04x", con_handle); 5146 return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 5147 } 5148 5149 l2cap_channel_t * channel = l2cap_create_channel_entry(packet_handler, L2CAP_CHANNEL_TYPE_CHANNEL_CBM, connection->address, connection->address_type, psm, mtu, security_level); 5150 if (!channel) { 5151 return BTSTACK_MEMORY_ALLOC_FAILED; 5152 } 5153 log_info("created %p", channel); 5154 5155 // store local_cid 5156 if (out_local_cid){ 5157 *out_local_cid = channel->local_cid; 5158 } 5159 5160 // setup channel entry 5161 channel->con_handle = con_handle; 5162 channel->receive_sdu_buffer = receive_sdu_buffer; 5163 channel->new_credits_incoming = initial_credits; 5164 channel->automatic_credits = initial_credits == L2CAP_LE_AUTOMATIC_CREDITS; 5165 5166 // add to connections list 5167 btstack_linked_list_add_tail(&l2cap_channels, (btstack_linked_item_t *) channel); 5168 5169 // check security level 5170 if (l2cap_cbm_security_level_for_connection(con_handle) < channel->required_security_level){ 5171 if (!sm_callback_registered){ 5172 sm_callback_registered = true; 5173 // lazy registration for SM events 5174 sm_event_callback_registration.callback = &l2cap_cbm_sm_packet_handler; 5175 sm_add_event_handler(&sm_event_callback_registration); 5176 } 5177 5178 // start pairing 5179 channel->state = L2CAP_STATE_WAIT_OUTGOING_SECURITY_LEVEL_UPDATE; 5180 sm_request_pairing(con_handle); 5181 } else { 5182 // send conn request right away 5183 channel->state = L2CAP_STATE_WILL_SEND_LE_CONNECTION_REQUEST; 5184 l2cap_run(); 5185 } 5186 5187 return ERROR_CODE_SUCCESS; 5188 } 5189 5190 uint8_t l2cap_cbm_provide_credits(uint16_t local_cid, uint16_t credits){ 5191 return l2cap_credit_based_provide_credits(local_cid, credits); 5192 } 5193 5194 bool l2cap_cbm_can_send_now(uint16_t local_cid){ 5195 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 5196 if (!channel) { 5197 log_error("le can send now, no channel for cid 0x%02x", local_cid); 5198 return false; 5199 } 5200 5201 // check state 5202 if (channel->state != L2CAP_STATE_OPEN) return false; 5203 5204 // check queue 5205 if (channel->send_sdu_buffer) return false; 5206 5207 // fine, go ahead 5208 return true; 5209 } 5210 5211 uint8_t l2cap_cbm_request_can_send_now_event(uint16_t local_cid){ 5212 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 5213 if (!channel) { 5214 log_error("can send now, no channel for cid 0x%02x", local_cid); 5215 return L2CAP_LOCAL_CID_DOES_NOT_EXIST; 5216 } 5217 channel->waiting_for_can_send_now = 1; 5218 l2cap_cbm_notify_channel_can_send(channel); 5219 return ERROR_CODE_SUCCESS; 5220 } 5221 5222 uint8_t l2cap_cbm_send_data(uint16_t local_cid, uint8_t * data, uint16_t size){ 5223 return l2cap_credit_based_send_data(local_cid, data, size); 5224 } 5225 5226 uint8_t l2cap_cbm_disconnect(uint16_t local_cid){ 5227 return l2cap_credit_based_disconnect(local_cid); 5228 } 5229 #endif 5230 5231 #ifdef ENABLE_L2CAP_ENHANCED_CREDIT_BASED_FLOW_CONTROL_MODE 5232 5233 uint8_t l2cap_ecbm_register_service(btstack_packet_handler_t packet_handler, uint16_t psm, uint16_t min_remote_mtu, gap_security_level_t security_level){ 5234 5235 // check for already registered psm 5236 l2cap_service_t *service = l2cap_cbm_get_service(psm); 5237 if (service) { 5238 return L2CAP_SERVICE_ALREADY_REGISTERED; 5239 } 5240 5241 // alloc structure 5242 service = btstack_memory_l2cap_service_get(); 5243 if (!service) { 5244 log_error("register: no memory for l2cap_service_t"); 5245 return BTSTACK_MEMORY_ALLOC_FAILED; 5246 } 5247 5248 // fill in 5249 service->psm = psm; 5250 service->mtu = min_remote_mtu; 5251 service->packet_handler = packet_handler; 5252 service->required_security_level = security_level; 5253 5254 // add to services list 5255 btstack_linked_list_add(&l2cap_enhanced_services, (btstack_linked_item_t *) service); 5256 5257 // done 5258 return ERROR_CODE_SUCCESS; 5259 } 5260 5261 uint8_t l2cap_ecbm_unregister_service(uint16_t psm) { 5262 l2cap_service_t *service = l2cap_cbm_get_service(psm); 5263 if (!service) return L2CAP_SERVICE_DOES_NOT_EXIST; 5264 5265 btstack_linked_list_remove(&l2cap_enhanced_services, (btstack_linked_item_t *) service); 5266 btstack_memory_l2cap_service_free(service); 5267 return ERROR_CODE_SUCCESS; 5268 } 5269 5270 void l2cap_ecbm_mps_set_min(uint16_t mps_min){ 5271 l2cap_enhanced_mps_min = mps_min; 5272 } 5273 5274 void l2cap_ecbm_mps_set_max(uint16_t mps_max){ 5275 l2cap_enhanced_mps_max = mps_max; 5276 } 5277 5278 uint8_t l2cap_ecbm_create_channels(btstack_packet_handler_t packet_handler, hci_con_handle_t con_handle, 5279 gap_security_level_t security_level, 5280 uint16_t psm, uint8_t num_channels, uint16_t initial_credits, uint16_t mtu, 5281 uint8_t ** receive_sdu_buffers, uint16_t * out_local_cid){ 5282 5283 log_info("create enhanced, handle 0x%04x psm 0x%x mtu %u", con_handle, psm, mtu); 5284 5285 hci_connection_t * connection = hci_connection_for_handle(con_handle); 5286 if (!connection) { 5287 log_error("no hci_connection for handle 0x%04x", con_handle); 5288 return ERROR_CODE_UNKNOWN_CONNECTION_IDENTIFIER; 5289 } 5290 5291 // setup all channels 5292 btstack_linked_list_t channels = NULL; 5293 uint8_t status = l2cap_ecbm_setup_channels(&channels, packet_handler, num_channels, connection, psm, mtu, 5294 security_level); 5295 5296 // add to connections list and set state + local_sig_id 5297 l2cap_channel_t * channel; 5298 uint8_t i = 0; 5299 uint8_t local_sig_id = l2cap_next_sig_id(); 5300 while (true) { 5301 channel = (l2cap_channel_t *) btstack_linked_list_pop(&channels); 5302 if (channel == NULL) break; 5303 channel->state = L2CAP_STATE_WILL_SEND_ENHANCED_CONNECTION_REQUEST; 5304 channel->local_sig_id = local_sig_id; 5305 channel->cid_index = i; 5306 channel->num_cids = num_channels; 5307 channel->credits_incoming = initial_credits; 5308 channel->automatic_credits = initial_credits == L2CAP_LE_AUTOMATIC_CREDITS; 5309 channel->receive_sdu_buffer = receive_sdu_buffers[i]; 5310 // store local_cid 5311 if (out_local_cid){ 5312 out_local_cid[i] = channel->local_cid; 5313 } 5314 btstack_linked_list_add_tail(&l2cap_channels, (btstack_linked_item_t *) channel); 5315 i++; 5316 } 5317 5318 #if 0 5319 // check security level 5320 if (l2cap_le_security_level_for_connection(con_handle) < channel->required_security_level){ 5321 if (!sm_callback_registered){ 5322 sm_callback_registered = true; 5323 // lazy registration for SM events 5324 sm_event_callback_registration.callback = &l2cap_sm_packet_handler; 5325 sm_add_event_handler(&sm_event_callback_registration); 5326 } 5327 5328 // start pairing 5329 channel->state = L2CAP_STATE_WAIT_OUTGOING_SECURITY_LEVEL_UPDATE; 5330 sm_request_pairing(con_handle); 5331 } else { 5332 // send conn request right away 5333 channel->state = L2CAP_STATE_WILL_SEND_LE_CONNECTION_REQUEST; 5334 l2cap_run(); 5335 } 5336 #endif 5337 5338 l2cap_run(); 5339 5340 return status; 5341 } 5342 5343 uint8_t l2cap_ecbm_accept_channels(uint16_t local_cid, uint8_t num_channels, uint16_t initial_credits, 5344 uint16_t receive_buffer_size, uint8_t ** receive_buffers, uint16_t * out_local_cids){ 5345 5346 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 5347 if (!channel) { 5348 5349 return L2CAP_LOCAL_CID_DOES_NOT_EXIST; 5350 } 5351 // 5352 hci_con_handle_t con_handle = channel->con_handle; 5353 uint8_t local_sig_id = channel->local_sig_id; 5354 uint8_t channel_index = 0; 5355 btstack_linked_list_iterator_t it; 5356 btstack_linked_list_iterator_init(&it, &l2cap_channels); 5357 while (btstack_linked_list_iterator_has_next(&it)) { 5358 channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 5359 if (!l2cap_is_dynamic_channel_type(channel->channel_type)) continue; 5360 if (channel->con_handle != con_handle) continue; 5361 if (channel->local_sig_id != local_sig_id) continue; 5362 if (channel->state != L2CAP_STATE_WAIT_CLIENT_ACCEPT_OR_REJECT) continue; 5363 5364 if (channel_index < num_channels){ 5365 // assign buffer and cid 5366 out_local_cids[channel_index] = channel->local_cid; 5367 channel->receive_sdu_buffer = receive_buffers[channel_index]; 5368 channel->local_mtu = receive_buffer_size; 5369 channel->credits_incoming = initial_credits; 5370 channel->automatic_credits = initial_credits == L2CAP_LE_AUTOMATIC_CREDITS; 5371 channel_index++; 5372 } else { 5373 // clear local cid for response packet 5374 channel->local_cid = 0; 5375 channel->reason = L2CAP_ECBM_CONNECTION_RESULT_SOME_REFUSED_INSUFFICIENT_RESOURCES_AVAILABLE; 5376 } 5377 // update state 5378 channel->state = L2CAP_STATE_WILL_SEND_ENHANCED_CONNECTION_RESPONSE; 5379 } 5380 l2cap_run(); 5381 return ERROR_CODE_SUCCESS; 5382 } 5383 5384 uint8_t l2cap_ecbm_decline_channels(uint16_t local_cid, uint16_t result){ 5385 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 5386 if (!channel) { 5387 return L2CAP_LOCAL_CID_DOES_NOT_EXIST; 5388 } 5389 // 5390 hci_con_handle_t con_handle = channel->con_handle; 5391 uint8_t local_sig_id = channel->local_sig_id; 5392 btstack_linked_list_iterator_t it; 5393 btstack_linked_list_iterator_init(&it, &l2cap_channels); 5394 while (btstack_linked_list_iterator_has_next(&it)) { 5395 channel = (l2cap_channel_t *) btstack_linked_list_iterator_next(&it); 5396 if (!l2cap_is_dynamic_channel_type(channel->channel_type)) continue; 5397 if (channel->con_handle != con_handle) continue; 5398 if (channel->local_sig_id != local_sig_id) continue; 5399 if (channel->state != L2CAP_STATE_WAIT_CLIENT_ACCEPT_OR_REJECT) continue; 5400 5401 // prepare response 5402 channel->local_cid = 0; 5403 channel->reason = result; 5404 channel->state = L2CAP_STATE_WILL_SEND_ENHANCED_CONNECTION_RESPONSE; 5405 } 5406 l2cap_run(); 5407 return ERROR_CODE_SUCCESS; 5408 } 5409 5410 uint8_t l2cap_ecbm_request_can_send_now_event(uint16_t local_cid){ 5411 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cid); 5412 if (!channel) { 5413 log_error("can send now, no channel for cid 0x%02x", local_cid); 5414 return L2CAP_LOCAL_CID_DOES_NOT_EXIST; 5415 } 5416 channel->waiting_for_can_send_now = 1; 5417 l2cap_cbm_notify_channel_can_send(channel); 5418 return ERROR_CODE_SUCCESS; 5419 } 5420 5421 uint8_t l2cap_ecbm_reconfigure_channels(uint8_t num_cids, uint16_t * local_cids, int16_t receive_buffer_size, uint8_t ** receive_buffers){ 5422 btstack_assert(receive_buffers != NULL); 5423 btstack_assert(local_cids != NULL); 5424 5425 if (num_cids > L2CAP_ECBM_MAX_CID_ARRAY_SIZE){ 5426 return ERROR_CODE_UNACCEPTABLE_CONNECTION_PARAMETERS; 5427 } 5428 5429 // check if all cids exist and have the same con handle 5430 uint8_t i; 5431 hci_con_handle_t con_handle = HCI_CON_HANDLE_INVALID; 5432 for (i = 0 ; i < num_cids ; i++){ 5433 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cids[i]); 5434 if (!channel) { 5435 return L2CAP_LOCAL_CID_DOES_NOT_EXIST; 5436 } 5437 if (channel->state != L2CAP_STATE_OPEN){ 5438 return ERROR_CODE_COMMAND_DISALLOWED; 5439 } 5440 if (con_handle == HCI_CON_HANDLE_INVALID){ 5441 con_handle = channel->con_handle; 5442 } else if (con_handle != channel->con_handle){ 5443 return ERROR_CODE_UNACCEPTABLE_CONNECTION_PARAMETERS; 5444 } 5445 } 5446 // set renegotiation data and state 5447 uint8_t sig_id = l2cap_next_sig_id(); 5448 for (i = 0 ; i < num_cids ; i++){ 5449 l2cap_channel_t * channel = l2cap_get_channel_for_local_cid(local_cids[i]); 5450 channel->cid_index = i; 5451 channel->num_cids = num_cids; 5452 channel->local_sig_id = sig_id; 5453 channel->renegotiate_mtu = receive_buffer_size; 5454 channel->renegotiate_sdu_buffer = receive_buffers[i]; 5455 channel->state = L2CAP_STATE_WILL_SEND_EHNANCED_RENEGOTIATION_REQUEST; 5456 } 5457 5458 5459 l2cap_run(); 5460 return ERROR_CODE_SUCCESS; 5461 } 5462 5463 uint8_t l2cap_ecbm_send_data(uint16_t local_cid, const uint8_t * data, uint16_t size){ 5464 return l2cap_credit_based_send_data(local_cid, data, size); 5465 } 5466 5467 uint8_t l2cap_ecbm_provide_credits(uint16_t local_cid, uint16_t credits){ 5468 return l2cap_credit_based_provide_credits(local_cid, credits); 5469 } 5470 5471 uint8_t l2cap_ecbm_disconnect(uint16_t local_cid){ 5472 return l2cap_credit_based_disconnect(local_cid); 5473 } 5474 #endif 5475 5476 #ifdef ENABLE_L2CAP_ENHANCED_RETRANSMISSION_MODE 5477 // @deprecated - please use l2cap_ertm_create_channel 5478 uint8_t l2cap_create_ertm_channel(btstack_packet_handler_t packet_handler, bd_addr_t address, uint16_t psm, 5479 l2cap_ertm_config_t * ertm_contig, uint8_t * buffer, uint32_t size, uint16_t * out_local_cid){ 5480 log_error("deprecated - please use l2cap_ertm_create_channel"); 5481 return l2cap_ertm_create_channel(packet_handler, address, psm, ertm_contig, buffer, size, out_local_cid); 5482 }; 5483 5484 // @deprecated - please use l2cap_ertm_accept_connection 5485 uint8_t l2cap_accept_ertm_connection(uint16_t local_cid, l2cap_ertm_config_t * ertm_contig, uint8_t * buffer, uint32_t size){ 5486 log_error("deprecated - please use l2cap_ertm_accept_connection"); 5487 return l2cap_ertm_accept_connection(local_cid, ertm_contig, buffer, size); 5488 } 5489 #endif 5490 5491 #ifdef ENABLE_L2CAP_LE_CREDIT_BASED_FLOW_CONTROL_MODE 5492 // @deprecated - please use l2cap_cbm_register_service 5493 uint8_t l2cap_le_register_service(btstack_packet_handler_t packet_handler, uint16_t psm, gap_security_level_t security_level){ 5494 log_error("deprecated - please use l2cap_cbm_register_service"); 5495 return l2cap_cbm_register_service(packet_handler, psm, security_level); 5496 } 5497 5498 // @deprecated - please use l2cap_cbm_unregister_service 5499 uint8_t l2cap_le_unregister_service(uint16_t psm){ 5500 log_error("deprecated - please use l2cap_cbm_unregister_service"); 5501 return l2cap_cbm_unregister_service(psm); 5502 } 5503 5504 // @deprecated - please use l2cap_cbm_accept_connection 5505 uint8_t l2cap_le_accept_connection(uint16_t local_cid, uint8_t * receive_sdu_buffer, uint16_t mtu, uint16_t initial_credits){ 5506 log_error("deprecated - please use l2cap_cbm_accept_connection"); 5507 return l2cap_cbm_accept_connection(local_cid, receive_sdu_buffer, mtu, initial_credits); 5508 } 5509 5510 // @deprecated - please use l2cap_cbm_decline_connection 5511 uint8_t l2cap_le_decline_connection(uint16_t local_cid){ 5512 log_error("deprecated - please use l2cap_cbm_decline_connection"); 5513 return l2cap_cbm_decline_connection(local_cid, L2CAP_CBM_CONNECTION_RESULT_NO_RESOURCES_AVAILABLE); 5514 } 5515 5516 // @deprecated - please use l2cap_cbm_create_channel 5517 uint8_t l2cap_le_create_channel(btstack_packet_handler_t packet_handler, hci_con_handle_t con_handle, 5518 uint16_t psm, uint8_t * receive_sdu_buffer, uint16_t mtu, uint16_t initial_credits, gap_security_level_t security_level, 5519 uint16_t * out_local_cid){ 5520 log_error("deprecated - please use l2cap_cbm_create_channel"); 5521 return l2cap_cbm_create_channel(packet_handler, con_handle, psm, receive_sdu_buffer, mtu, initial_credits, security_level, out_local_cid); 5522 } 5523 5524 // @deprecated - please use l2cap_cbm_provide_credits 5525 uint8_t l2cap_le_provide_credits(uint16_t local_cid, uint16_t credits){ 5526 log_error("deprecated - please use l2cap_cbm_provide_credits"); 5527 return l2cap_cbm_provide_credits(local_cid, credits); 5528 } 5529 5530 // @deprecated - please use l2cap_cbm_can_send_now 5531 bool l2cap_le_can_send_now(uint16_t local_cid){ 5532 log_error("deprecated - please use l2cap_cbm_can_send_now"); 5533 return l2cap_cbm_can_send_now(local_cid); 5534 } 5535 5536 // @deprecated - please use l2cap_cbm_request_can_send_now_event 5537 uint8_t l2cap_le_request_can_send_now_event(uint16_t local_cid){ 5538 log_error("deprecated - please use l2cap_cbm_request_can_send_now_event"); 5539 return l2cap_cbm_request_can_send_now_event(local_cid); 5540 } 5541 5542 // @deprecated - please use l2cap_cbm_send_data 5543 uint8_t l2cap_le_send_data(uint16_t local_cid, uint8_t * data, uint16_t size){ 5544 log_error("deprecated - please use l2cap_cbm_send_data"); 5545 return l2cap_cbm_send_data(local_cid, data, size); 5546 } 5547 5548 // @deprecated - please use l2cap_cbm_disconnect 5549 uint8_t l2cap_le_disconnect(uint16_t local_cid){ 5550 log_error("deprecated - please use l2cap_cbm_disconnect"); 5551 return l2cap_cbm_disconnect(local_cid); 5552 } 5553 #endif 5554