1 /* 2 * Copyright (C) 2009-2012 by Matthias Ringwald 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 MATTHIAS RINGWALD 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 [email protected] 34 * 35 */ 36 37 /* 38 * l2cap.h 39 * 40 * Logical Link Control and Adaption Protocl (L2CAP) 41 * 42 * Created by Matthias Ringwald on 5/16/09. 43 */ 44 45 #pragma once 46 47 #include "hci.h" 48 #include "l2cap_signaling.h" 49 #include <btstack/utils.h> 50 #include <btstack/btstack.h> 51 52 #if defined __cplusplus 53 extern "C" { 54 #endif 55 56 #define L2CAP_SIG_ID_INVALID 0 57 58 #define L2CAP_HEADER_SIZE 4 59 60 // size of HCI ACL + L2CAP Header for regular data packets (8) 61 #define COMPLETE_L2CAP_HEADER (HCI_ACL_HEADER_SIZE + L2CAP_HEADER_SIZE) 62 63 // minimum signaling MTU 64 #define L2CAP_MINIMAL_MTU 48 65 #define L2CAP_DEFAULT_MTU 672 66 67 // check L2CAP MTU 68 #if (L2CAP_MINIMAL_MTU + L2CAP_HEADER_SIZE) > HCI_ACL_PAYLOAD_SIZE 69 #error "HCI_ACL_PAYLOAD_SIZE too small for minimal L2CAP MTU of 48 bytes" 70 #endif 71 72 // L2CAP Fixed Channel IDs 73 #define L2CAP_CID_SIGNALING 0x0001 74 #define L2CAP_CID_CONNECTIONLESS_CHANNEL 0x0002 75 #define L2CAP_CID_ATTRIBUTE_PROTOCOL 0x0004 76 #define L2CAP_CID_SIGNALING_LE 0x0005 77 #define L2CAP_CID_SECURITY_MANAGER_PROTOCOL 0x0006 78 79 // L2CAP Configuration Result Codes 80 #define L2CAP_CONF_RESULT_UNKNOWN_OPTIONS 0x0003 81 82 // L2CAP Reject Result Codes 83 #define L2CAP_REJ_CMD_UNKNOWN 0x0000 84 85 // Response Timeout eXpired 86 #define L2CAP_RTX_TIMEOUT_MS 2000 87 88 // Extended Response Timeout eXpired 89 #define L2CAP_ERTX_TIMEOUT_MS 120000 90 91 // private structs 92 typedef enum { 93 L2CAP_STATE_CLOSED = 1, // no baseband 94 L2CAP_STATE_WILL_SEND_CREATE_CONNECTION, 95 L2CAP_STATE_WAIT_CONNECTION_COMPLETE, 96 L2CAP_STATE_WAIT_SECURITY_LEVEL_UPDATE, 97 L2CAP_STATE_WAIT_CLIENT_ACCEPT_OR_REJECT, 98 L2CAP_STATE_WAIT_CONNECT_RSP, // from peer 99 L2CAP_STATE_CONFIG, 100 L2CAP_STATE_OPEN, 101 L2CAP_STATE_WAIT_DISCONNECT, // from application 102 L2CAP_STATE_WILL_SEND_CONNECTION_REQUEST, 103 L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_INSUFFICIENT_SECURITY, 104 L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_DECLINE, 105 L2CAP_STATE_WILL_SEND_CONNECTION_RESPONSE_ACCEPT, 106 L2CAP_STATE_WILL_SEND_DISCONNECT_REQUEST, 107 L2CAP_STATE_WILL_SEND_DISCONNECT_RESPONSE, 108 } L2CAP_STATE; 109 110 typedef enum { 111 L2CAP_CHANNEL_STATE_VAR_NONE = 0, 112 L2CAP_CHANNEL_STATE_VAR_RCVD_CONF_REQ = 1 << 0, 113 L2CAP_CHANNEL_STATE_VAR_RCVD_CONF_RSP = 1 << 1, 114 L2CAP_CHANNEL_STATE_VAR_SEND_CONF_REQ = 1 << 2, 115 L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP = 1 << 3, 116 L2CAP_CHANNEL_STATE_VAR_SENT_CONF_REQ = 1 << 4, 117 L2CAP_CHANNEL_STATE_VAR_SENT_CONF_RSP = 1 << 5, 118 L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_MTU = 1 << 6, // in CONF RSP, add MTU field 119 L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_CONT = 1 << 7, // in CONF RSP, set CONTINUE flag 120 L2CAP_CHANNEL_STATE_VAR_SEND_CONF_RSP_INVALID = 1 << 8, // in CONF RSP, send UNKNOWN OPTIONS 121 L2CAP_CHANNEL_STATE_VAR_SEND_CMD_REJ_UNKNOWN = 1 << 9, // send CMD_REJ with reason unknown 122 L2CAP_CHANNEL_STATE_VAR_SEND_CONN_RESP_PEND = 1 << 10, // send Connection Respond with pending 123 } L2CAP_CHANNEL_STATE_VAR; 124 125 // info regarding an actual coneection 126 typedef struct { 127 // linked list - assert: first field 128 linked_item_t item; 129 130 L2CAP_STATE state; 131 L2CAP_CHANNEL_STATE_VAR state_var; 132 133 bd_addr_t address; 134 hci_con_handle_t handle; 135 136 uint8_t remote_sig_id; // used by other side, needed for delayed response 137 uint8_t local_sig_id; // own signaling identifier 138 139 uint16_t local_cid; 140 uint16_t remote_cid; 141 142 uint16_t local_mtu; 143 uint16_t remote_mtu; 144 145 uint16_t flush_timeout; // default 0xffff 146 147 uint16_t psm; 148 149 gap_security_level_t required_security_level; 150 151 uint8_t packets_granted; // number of L2CAP/ACL packets client is allowed to send 152 153 uint8_t reason; // used in decline internal 154 155 timer_source_t rtx; // also used for ertx 156 157 // client connection 158 void * connection; 159 160 // internal connection 161 btstack_packet_handler_t packet_handler; 162 163 } l2cap_channel_t; 164 165 // info regarding potential connections 166 typedef struct { 167 // linked list - assert: first field 168 linked_item_t item; 169 170 // service id 171 uint16_t psm; 172 173 // incoming MTU 174 uint16_t mtu; 175 176 // client connection 177 void *connection; 178 179 // internal connection 180 btstack_packet_handler_t packet_handler; 181 182 // required security level 183 gap_security_level_t security_level; 184 } l2cap_service_t; 185 186 187 typedef struct l2cap_signaling_response { 188 hci_con_handle_t handle; 189 uint8_t sig_id; 190 uint8_t code; 191 uint16_t data; // infoType for INFORMATION REQUEST, result for CONNECTION request and command unknown 192 } l2cap_signaling_response_t; 193 194 195 void l2cap_block_new_credits(uint8_t blocked); 196 int l2cap_can_send_packet_now(uint16_t local_cid); // non-blocking UART write 197 198 // get outgoing buffer and prepare data 199 uint8_t *l2cap_get_outgoing_buffer(void); 200 201 int l2cap_send_prepared(uint16_t local_cid, uint16_t len); 202 203 int l2cap_send_prepared_connectionless(uint16_t handle, uint16_t cid, uint16_t len); 204 205 // Bluetooth 4.0 - allows to register handler for Attribute Protocol and Security Manager Protocol 206 void l2cap_register_fixed_channel(btstack_packet_handler_t packet_handler, uint16_t channel_id); 207 208 uint16_t l2cap_max_mtu(void); 209 210 int l2cap_send_connectionless(uint16_t handle, uint16_t cid, uint8_t *data, uint16_t len); 211 212 void l2cap_close_connection(void *connection); 213 214 215 /** Embedded API **/ 216 217 // Set up L2CAP and register L2CAP with HCI layer. 218 void l2cap_init(void); 219 220 // Registers a packet handler that handles HCI and general BTstack events. 221 void l2cap_register_packet_handler(void (*handler)(void * connection, uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size)); 222 223 // Creates L2CAP channel to the PSM of a remote device with baseband address. A new baseband connection will be initiated if necessary. 224 void l2cap_create_channel_internal(void * connection, btstack_packet_handler_t packet_handler, bd_addr_t address, uint16_t psm, uint16_t mtu); 225 226 // Disconencts L2CAP channel with given identifier. 227 void l2cap_disconnect_internal(uint16_t local_cid, uint8_t reason); 228 229 // Queries the maximal transfer unit (MTU) for L2CAP channel with given identifier. 230 uint16_t l2cap_get_remote_mtu_for_local_cid(uint16_t local_cid); 231 232 // Sends L2CAP data packet to the channel with given identifier. 233 int l2cap_send_internal(uint16_t local_cid, uint8_t *data, uint16_t len); 234 235 // Registers L2CAP service with given PSM and MTU, and assigns a packet handler. On embedded systems, use NULL for connection parameter. 236 void l2cap_register_service_internal(void *connection, btstack_packet_handler_t packet_handler, uint16_t psm, uint16_t mtu, gap_security_level_t security_level); 237 238 // Unregisters L2CAP service with given PSM. On embedded systems, use NULL for connection parameter. 239 void l2cap_unregister_service_internal(void *connection, uint16_t psm); 240 241 // Accepts/Deny incoming L2CAP connection. 242 void l2cap_accept_connection_internal(uint16_t local_cid); 243 void l2cap_decline_connection_internal(uint16_t local_cid, uint8_t reason); 244 245 // Request LE connection parameter update 246 int l2cap_le_request_connection_parameter_update(uint16_t handle, uint16_t interval_min, uint16_t interval_max, uint16_t slave_latency, uint16_t timeout_multiplier); 247 248 #if defined __cplusplus 249 } 250 #endif 251