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