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 #define __BTSTACK_FILE__ "l2cap_signaling.c" 39 40 /* 41 * l2cap_signaling.h 42 * 43 * Created by Matthias Ringwald on 7/23/09. 44 */ 45 46 #include "l2cap_signaling.h" 47 #include "btstack_config.h" 48 #include "btstack_debug.h" 49 #include "hci.h" 50 51 #include <string.h> 52 53 static const char *l2cap_signaling_commands_format[] = { 54 "2D", // 0x01 command reject: reason {cmd not understood (0), sig MTU exceeded (2:max sig MTU), invalid CID (4:req CID)}, data len, data 55 "22", // 0x02 connection request: PSM, Source CID 56 "2222", // 0x03 connection response: Dest CID, Source CID, Result, Status 57 "22D", // 0x04 config request: Dest CID, Flags, Configuration options 58 "222D", // 0x05 config response: Source CID, Flags, Result, Configuration options 59 "22", // 0x06 disconection request: Dest CID, Source CID 60 "22", // 0x07 disconection response: Dest CID, Source CID 61 "D", // 0x08 echo request: Data 62 "D", // 0x09 echo response: Data 63 "2", // 0x0a information request: InfoType {1=Connectionless MTU, 2=Extended features supported} 64 "22D", // 0x0b information response: InfoType, Result, Data 65 #ifdef ENABLE_BLE 66 NULL, // 0x0c non-supported AMP command 67 NULL, // 0x0d non-supported AMP command 68 NULL, // 0x0e non-supported AMP command 69 NULL, // 0x0f non-supported AMP command 70 NULL, // 0x10 non-supported AMP command 71 NULL, // 0x11 non-supported AMP command 72 "2222", // 0x12 connection parameter update request: interval min, interval max, slave latency, timeout multipler 73 "2", // 0x13 connection parameter update response: result 74 "22222", // 0X14 le credit based connection request: le psm, source cid, mtu, mps, initial credits 75 "22222", // 0x15 le credit based connection respone: dest cid, mtu, mps, initial credits, result 76 "22", // 0x16 le flow control credit: source cid, credits 77 #endif 78 }; 79 80 static const unsigned int num_l2cap_commands = sizeof(l2cap_signaling_commands_format) / sizeof(const char *); 81 82 uint8_t sig_seq_nr = 0xff; 83 uint16_t source_cid = 0x40; 84 85 uint8_t l2cap_next_sig_id(void){ 86 if (sig_seq_nr == 0xff) { 87 sig_seq_nr = 1; 88 } else { 89 sig_seq_nr++; 90 } 91 return sig_seq_nr; 92 } 93 94 uint16_t l2cap_next_local_cid(void){ 95 return source_cid++; 96 } 97 98 static uint16_t l2cap_create_signaling_internal(uint8_t * acl_buffer, hci_con_handle_t handle, uint16_t cid, L2CAP_SIGNALING_COMMANDS cmd, uint8_t identifier, va_list argptr){ 99 100 const char *format = NULL; 101 if (cmd > 0 && cmd <= num_l2cap_commands) { 102 format = l2cap_signaling_commands_format[cmd-1]; 103 } 104 if (!format){ 105 log_error("l2cap_create_signaling_internal: invalid command id 0x%02x", cmd); 106 return 0; 107 } 108 109 int pb = hci_non_flushable_packet_boundary_flag_supported() ? 0x00 : 0x02; 110 111 // 0 - Connection handle : PB=pb : BC=00 112 little_endian_store_16(acl_buffer, 0, handle | (pb << 12) | (0 << 14)); 113 // 6 - L2CAP channel = 1 114 little_endian_store_16(acl_buffer, 6, cid); 115 // 8 - Code 116 acl_buffer[8] = cmd; 117 // 9 - id (!= 0 sequentially) 118 acl_buffer[9] = identifier; 119 120 // 12 - L2CAP signaling parameters 121 uint16_t pos = 12; 122 uint16_t word; 123 uint8_t * ptr; 124 while (*format) { 125 switch(*format) { 126 case '1': // 8 bit value 127 case '2': // 16 bit value 128 word = va_arg(argptr, int); 129 // minimal va_arg is int: 2 bytes on 8+16 bit CPUs 130 acl_buffer[pos++] = word & 0xff; 131 if (*format == '2') { 132 acl_buffer[pos++] = word >> 8; 133 } 134 break; 135 case 'D': // variable data. passed: len, ptr 136 word = va_arg(argptr, int); 137 ptr = va_arg(argptr, uint8_t *); 138 memcpy(&acl_buffer[pos], ptr, word); 139 pos += word; 140 break; 141 default: 142 break; 143 } 144 format++; 145 }; 146 va_end(argptr); 147 148 // Fill in various length fields: it's the number of bytes following for ACL lenght and l2cap parameter length 149 // - the l2cap payload length is counted after the following channel id (only payload) 150 151 // 2 - ACL length 152 little_endian_store_16(acl_buffer, 2, pos - 4); 153 // 4 - L2CAP packet length 154 little_endian_store_16(acl_buffer, 4, pos - 6 - 2); 155 // 10 - L2CAP signaling parameter length 156 little_endian_store_16(acl_buffer, 10, pos - 12); 157 158 return pos; 159 } 160 161 uint16_t l2cap_create_signaling_classic(uint8_t * acl_buffer, hci_con_handle_t handle, L2CAP_SIGNALING_COMMANDS cmd, uint8_t identifier, va_list argptr){ 162 return l2cap_create_signaling_internal(acl_buffer, handle, 1, cmd, identifier, argptr); 163 } 164 165 #ifdef ENABLE_BLE 166 uint16_t l2cap_create_signaling_le(uint8_t * acl_buffer, hci_con_handle_t handle, L2CAP_SIGNALING_COMMANDS cmd, uint8_t identifier, va_list argptr){ 167 return l2cap_create_signaling_internal(acl_buffer, handle, 5, cmd, identifier, argptr); 168 } 169 #endif 170