1 /* 2 * Copyright (C) 2014 BlueKitchen GmbH 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. Neither the name of the copyright holders nor the names of 14 * contributors may be used to endorse or promote products derived 15 * from this software without specific prior written permission. 16 * 4. Any redistribution, use, or modification is done solely for 17 * personal benefit and not for any commercial purpose or for 18 * monetary gain. 19 * 20 * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS 24 * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 27 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 30 * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * Please inquire about commercial licensing options at 34 * [email protected] 35 * 36 */ 37 38 /* 39 * l2cap.h 40 * 41 * Logical Link Control and Adaption Protocol (L2CAP) 42 * 43 * Created by Matthias Ringwald on 5/16/09. 44 */ 45 46 #ifndef __L2CAP_H 47 #define __L2CAP_H 48 49 #include "hci.h" 50 #include "l2cap_signaling.h" 51 #include "btstack_util.h" 52 #include "bluetooth.h" 53 54 #if defined __cplusplus 55 extern "C" { 56 #endif 57 58 // check L2CAP MTU 59 #if (L2CAP_MINIMAL_MTU + L2CAP_HEADER_SIZE) > HCI_ACL_PAYLOAD_SIZE 60 #error "HCI_ACL_PAYLOAD_SIZE too small for minimal L2CAP MTU of 48 bytes" 61 #endif 62 63 // private structs 64 typedef enum { 65 L2CAP_STATE_CLOSED = 1, // no baseband 66 L2CAP_STATE_WILL_SEND_CREATE_CONNECTION, 67 L2CAP_STATE_WAIT_CONNECTION_COMPLETE, 68 L2CAP_STATE_WAIT_REMOTE_SUPPORTED_FEATURES, 69 L2CAP_STATE_WAIT_INCOMING_SECURITY_LEVEL_UPDATE, 70 L2CAP_STATE_WAIT_OUTGOING_SECURITY_LEVEL_UPDATE, 71 L2CAP_STATE_WAIT_CLIENT_ACCEPT_OR_REJECT, 72 L2CAP_STATE_WAIT_CONNECT_RSP, // from peer 73 L2CAP_STATE_CONFIG, 74 L2CAP_STATE_OPEN, 75 L2CAP_STATE_WAIT_DISCONNECT, // from application 76 L2CAP_STATE_WILL_SEND_CONNECTION_REQUEST, 77 L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_INSUFFICIENT_SECURITY, 78 L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_DECLINE, 79 L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_ACCEPT, 80 L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST, 81 L2CAP_STATE_WILL_SEND_DISCONNECT_RESPONSE, 82 L2CAP_STATE_INVALID, 83 } L2CAP_STATE; 84 85 typedef enum { 86 L2CAP_CHANNEL_STATE_VAR_NONE = 0, 87 L2CAP_CHANNEL_STATE_VAR_RCVD_CONF_REQ = 1 << 0, 88 L2CAP_CHANNEL_STATE_VAR_RCVD_CONF_RSP = 1 << 1, 89 L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ = 1 << 2, 90 L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP = 1 << 3, 91 L2CAP_CHANNEL_STATE_VAR_SENT_CONF_REQ = 1 << 4, 92 L2CAP_CHANNEL_STATE_VAR_SENT_CONF_RSP = 1 << 5, 93 L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_MTU = 1 << 6, // in CONF RSP, add MTU field 94 L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_CONT = 1 << 7, // in CONF RSP, set CONTINUE flag 95 L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_INVALID = 1 << 8, // in CONF RSP, send UNKNOWN OPTIONS 96 L2CAP_CHANNEL_STATE_VAR_SEND_CMD_REJ_UNKNOWN = 1 << 9, // send CMD_REJ with reason unknown 97 L2CAP_CHANNEL_STATE_VAR_SEND_CONN_RESP_PEND = 1 << 10, // send Connection Respond with pending 98 } L2CAP_CHANNEL_STATE_VAR; 99 100 // info regarding an actual connection 101 typedef struct { 102 // linked list - assert: first field 103 btstack_linked_item_t item; 104 105 // packet handler 106 btstack_packet_handler_t packet_handler; 107 108 // timer 109 btstack_timer_source_t rtx; // also used for ertx 110 111 L2CAP_STATE state; 112 L2CAP_CHANNEL_STATE_VAR state_var; 113 114 // info 115 bd_addr_t address; 116 hci_con_handle_t con_handle; 117 118 uint8_t remote_sig_id; // used by other side, needed for delayed response 119 uint8_t local_sig_id; // own signaling identifier 120 121 uint16_t local_cid; 122 uint16_t remote_cid; 123 124 uint16_t local_mtu; 125 uint16_t remote_mtu; 126 127 uint16_t flush_timeout; // default 0xffff 128 129 uint16_t psm; 130 131 gap_security_level_t required_security_level; 132 133 uint8_t reason; // used in decline internal 134 uint8_t waiting_for_can_send_now; 135 136 } l2cap_channel_t; 137 138 // info regarding potential connections 139 typedef struct { 140 // linked list - assert: first field 141 btstack_linked_item_t item; 142 143 // service id 144 uint16_t psm; 145 146 // incoming MTU 147 uint16_t mtu; 148 149 // incoming MPS 150 uint16_t mps; 151 152 // internal connection 153 btstack_packet_handler_t packet_handler; 154 155 // required security level 156 gap_security_level_t required_security_level; 157 } l2cap_service_t; 158 159 160 typedef struct l2cap_signaling_response { 161 hci_con_handle_t handle; 162 uint8_t sig_id; 163 uint8_t code; 164 uint16_t data; // infoType for INFORMATION REQUEST, result for CONNECTION request and command unknown 165 } l2cap_signaling_response_t; 166 167 168 void l2cap_register_fixed_channel(btstack_packet_handler_t packet_handler, uint16_t channel_id); 169 int l2cap_can_send_fixed_channel_packet_now(hci_con_handle_t con_handle, uint16_t channel_id); 170 void l2cap_request_can_send_fix_channel_now_event(hci_con_handle_t con_handle, uint16_t channel_id); 171 int l2cap_send_connectionless(hci_con_handle_t con_handle, uint16_t cid, uint8_t *data, uint16_t len); 172 int l2cap_send_prepared_connectionless(hci_con_handle_t con_handle, uint16_t cid, uint16_t len); 173 174 // PTS Testing 175 int l2cap_send_echo_request(hci_con_handle_t con_handle, uint8_t *data, uint16_t len); 176 void l2cap_require_security_level_2_for_outgoing_sdp(void); 177 178 // Used by RFCOMM - similar to l2cap_can-send_packet_now but does not check if outgoing buffer is reserved 179 int l2cap_can_send_prepared_packet_now(uint16_t local_cid); 180 181 /* API_START */ 182 183 /** 184 * @brief Set up L2CAP and register L2CAP with HCI layer. 185 */ 186 void l2cap_init(void); 187 188 /** 189 * @brief Registers packet handler for LE Connection Parameter Update events 190 */ 191 void l2cap_register_packet_handler(void (*handler)(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size)); 192 193 /** 194 * @brief Get max MTU for Classic connections based on btstack configuration 195 */ 196 uint16_t l2cap_max_mtu(void); 197 198 /** 199 * @brief Get max MTU for LE connections based on btstack configuration 200 */ 201 uint16_t l2cap_max_le_mtu(void); 202 203 /** 204 * @brief Creates L2CAP channel to the PSM of a remote device with baseband address. A new baseband connection will be initiated if necessary. 205 * @param packet_handler 206 * @param address 207 * @param psm 208 * @param mtu 209 * @param local_cid 210 * @return status 211 */ 212 uint8_t l2cap_create_channel(btstack_packet_handler_t packet_handler, bd_addr_t address, uint16_t psm, uint16_t mtu, uint16_t * out_local_cid); 213 214 /** 215 * @brief Disconnects L2CAP channel with given identifier. 216 */ 217 void l2cap_disconnect(uint16_t local_cid, uint8_t reason); 218 219 /** 220 * @brief Queries the maximal transfer unit (MTU) for L2CAP channel with given identifier. 221 */ 222 uint16_t l2cap_get_remote_mtu_for_local_cid(uint16_t local_cid); 223 224 /** 225 * @brief Sends L2CAP data packet to the channel with given identifier. 226 */ 227 int l2cap_send(uint16_t local_cid, uint8_t *data, uint16_t len); 228 229 /** 230 * @brief Registers L2CAP service with given PSM and MTU, and assigns a packet handler. 231 */ 232 uint8_t l2cap_register_service(btstack_packet_handler_t packet_handler, uint16_t psm, uint16_t mtu, gap_security_level_t security_level); 233 234 /** 235 * @brief Unregisters L2CAP service with given PSM. On embedded systems, use NULL for connection parameter. 236 */ 237 uint8_t l2cap_unregister_service(uint16_t psm); 238 239 /** 240 * @brief Accepts incoming L2CAP connection. 241 */ 242 void l2cap_accept_connection(uint16_t local_cid); 243 244 /** 245 * @brief Deny incoming L2CAP connection. 246 */ 247 void l2cap_decline_connection(uint16_t local_cid); 248 249 /** 250 * @brief Check if outgoing buffer is available and that there's space on the Bluetooth module 251 */ 252 int l2cap_can_send_packet_now(uint16_t local_cid); 253 254 /** 255 * @brief Request emission of L2CAP_EVENT_CAN_SEND_NOW as soon as possible 256 * @note L2CAP_EVENT_CAN_SEND_NOW might be emitted during call to this function 257 * so packet handler should be ready to handle it 258 * @param local_cid 259 */ 260 void l2cap_request_can_send_now_event(uint16_t local_cid); 261 262 /** 263 * @brief Reserve outgoing buffer 264 */ 265 int l2cap_reserve_packet_buffer(void); 266 267 /** 268 * @brief Get outgoing buffer and prepare data. 269 */ 270 uint8_t *l2cap_get_outgoing_buffer(void); 271 272 /** 273 * @brief Send L2CAP packet prepared in outgoing buffer to channel 274 */ 275 int l2cap_send_prepared(uint16_t local_cid, uint16_t len); 276 277 /** 278 * @brief Release outgoing buffer (only needed if l2cap_send_prepared is not called) 279 */ 280 void l2cap_release_packet_buffer(void); 281 282 /* API_END */ 283 284 #if 0 285 286 // to be implemented soon 287 /** 288 * @brief Regster L2CAP LE Credit Based Flow Control Mode service 289 * @param 290 */ 291 void l2cap_le_register_service(btstack_packet_handler_t packet_handler, uint16_t psm, 292 uint16_t mtu, uint16_t mps, uint16_t initial_credits, gap_security_level_t security_level); 293 void l2cap_le_unregister_service(uint16_t psm); 294 #endif 295 296 #if defined __cplusplus 297 } 298 #endif 299 300 #endif // __L2CAP_H 301