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 L2CAP_STATE state; 106 L2CAP_CHANNEL_STATE_VAR state_var; 107 108 bd_addr_t address; 109 hci_con_handle_t handle; 110 111 uint8_t remote_sig_id; // used by other side, needed for delayed response 112 uint8_t local_sig_id; // own signaling identifier 113 114 uint16_t local_cid; 115 uint16_t remote_cid; 116 117 uint16_t local_mtu; 118 uint16_t remote_mtu; 119 120 uint16_t flush_timeout; // default 0xffff 121 122 uint16_t psm; 123 124 gap_security_level_t required_security_level; 125 126 uint8_t reason; // used in decline internal 127 128 btstack_timer_source_t rtx; // also used for ertx 129 130 // internal connection 131 btstack_packet_handler_t packet_handler; 132 133 } l2cap_channel_t; 134 135 // info regarding potential connections 136 typedef struct { 137 // linked list - assert: first field 138 btstack_linked_item_t item; 139 140 // service id 141 uint16_t psm; 142 143 // incoming MTU 144 uint16_t mtu; 145 146 // incoming MPS 147 uint16_t mps; 148 149 // internal connection 150 btstack_packet_handler_t packet_handler; 151 152 // required security level 153 gap_security_level_t required_security_level; 154 } l2cap_service_t; 155 156 157 typedef struct l2cap_signaling_response { 158 hci_con_handle_t handle; 159 uint8_t sig_id; 160 uint8_t code; 161 uint16_t data; // infoType for INFORMATION REQUEST, result for CONNECTION request and command unknown 162 } l2cap_signaling_response_t; 163 164 165 166 int l2cap_can_send_fixed_channel_packet_now(uint16_t handle); 167 void l2cap_register_fixed_channel(btstack_packet_handler_t packet_handler, uint16_t channel_id); 168 int l2cap_send_connectionless(uint16_t handle, uint16_t cid, uint8_t *data, uint16_t len); 169 int l2cap_send_prepared_connectionless(uint16_t handle, uint16_t cid, uint16_t len); 170 171 // PTS Testing 172 int l2cap_send_echo_request(uint16_t handle, uint8_t *data, uint16_t len); 173 void l2cap_require_security_level_2_for_outgoing_sdp(void); 174 175 /* API_START */ 176 177 /** 178 * @brief Set up L2CAP and register L2CAP with HCI layer. 179 */ 180 void l2cap_init(void); 181 182 /** 183 * @brief Registers a packet handler that handles HCI and general BTstack events. 184 */ 185 void l2cap_register_packet_handler(void (*handler)(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size)); 186 187 /** 188 * @brief Get max MTU for Classic connections based on btstack configuration 189 */ 190 uint16_t l2cap_max_mtu(void); 191 192 /** 193 * @brief Get max MTU for LE connections based on btstack configuration 194 */ 195 uint16_t l2cap_max_le_mtu(void); 196 197 /** 198 * @brief Creates L2CAP channel to the PSM of a remote device with baseband address. A new baseband connection will be initiated if necessary. 199 * @param packet_handler 200 * @param address 201 * @param psm 202 * @param mtu 203 * @param local_cid 204 * @param status 205 */ 206 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); 207 208 /** 209 * @brief Disconnects L2CAP channel with given identifier. 210 */ 211 void l2cap_disconnect(uint16_t local_cid, uint8_t reason); 212 213 /** 214 * @brief Queries the maximal transfer unit (MTU) for L2CAP channel with given identifier. 215 */ 216 uint16_t l2cap_get_remote_mtu_for_local_cid(uint16_t local_cid); 217 218 /** 219 * @brief Sends L2CAP data packet to the channel with given identifier. 220 */ 221 int l2cap_send(uint16_t local_cid, uint8_t *data, uint16_t len); 222 223 /** 224 * @brief Registers L2CAP service with given PSM and MTU, and assigns a packet handler. 225 */ 226 uint8_t l2cap_register_service(btstack_packet_handler_t packet_handler, uint16_t psm, uint16_t mtu, gap_security_level_t security_level); 227 228 /** 229 * @brief Unregisters L2CAP service with given PSM. On embedded systems, use NULL for connection parameter. 230 */ 231 void l2cap_unregister_service(uint16_t psm); 232 233 /** 234 * @brief Accepts incoming L2CAP connection. 235 */ 236 void l2cap_accept_connection(uint16_t local_cid); 237 238 /** 239 * @brief Deny incoming L2CAP connection. 240 */ 241 void l2cap_decline_connection(uint16_t local_cid, uint8_t reason); 242 243 /** 244 * @brief Check if outgoing buffer is available and that there's space on the Bluetooth module 245 */ 246 int l2cap_can_send_packet_now(uint16_t local_cid); 247 int l2cap_can_send_prepared_packet_now(uint16_t local_cid); 248 249 /** 250 * @brief Reserve outgoing buffer 251 */ 252 int l2cap_reserve_packet_buffer(void); 253 254 /** 255 * @brief Get outgoing buffer and prepare data. 256 */ 257 uint8_t *l2cap_get_outgoing_buffer(void); 258 259 /** 260 * @brief Send L2CAP packet prepared in outgoing buffer to channel 261 */ 262 int l2cap_send_prepared(uint16_t local_cid, uint16_t len); 263 264 /** 265 * @brief Release outgoing buffer (only needed if l2cap_send_prepared is not called) 266 */ 267 void l2cap_release_packet_buffer(void); 268 269 /* API_END */ 270 271 #if 0 272 273 // to be implemented soon 274 /** 275 * @brief Regster L2CAP LE Credit Based Flow Control Mode service 276 * @param 277 */ 278 void l2cap_le_register_service(btstack_packet_handler_t packet_handler, uint16_t psm, 279 uint16_t mtu, uint16_t mps, uint16_t initial_credits, gap_security_level_t security_level); 280 void l2cap_le_unregister_service(uint16_t psm); 281 #endif 282 283 #if defined __cplusplus 284 } 285 #endif 286 287 #endif // __L2CAP_H 288