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_signaling.h 39 * 40 * Created by Matthias Ringwald on 7/23/09. 41 */ 42 43 #include "l2cap_signaling.h" 44 #include "btstack-config.h" 45 46 #include <string.h> 47 48 static const char *l2cap_signaling_commands_format[] = { 49 "2D", // 0x01 command reject: reason {cmd not understood (0), sig MTU exceeded (2:max sig MTU), invalid CID (4:req CID)}, data len, data 50 "22", // 0x02 connection request: PSM, Source CID 51 "2222", // 0x03 connection response: Dest CID, Source CID, Result, Status 52 "22D", // 0x04 config request: Dest CID, Flags, Configuration options 53 "222D", // 0x05 config response: Source CID, Flags, Result, Configuration options 54 "22", // 0x06 disconection request: Dest CID, Source CID 55 "22", // 0x07 disconection response: Dest CID, Source CID 56 "D", // 0x08 echo request: Data 57 "D", // 0x09 echo response: Data 58 "2", // 0x0a information request: InfoType {1=Connectionless MTU, 2=Extended features supported} 59 "22D", // 0x0b information response: InfoType, Result, Data 60 #ifdef HAVE_BLE 61 // skip 6 not supported signaling pdus, see below 62 "2222", // 0x12 connection parameter update request: interval min, interval max, slave latency, timeout multipler 63 "2", // 0x13 connection parameter update response: result 64 #endif 65 }; 66 67 uint8_t sig_seq_nr = 0xff; 68 uint16_t source_cid = 0x40; 69 70 uint8_t l2cap_next_sig_id(void){ 71 if (sig_seq_nr == 0xff) { 72 sig_seq_nr = 1; 73 } else { 74 sig_seq_nr++; 75 } 76 return sig_seq_nr; 77 } 78 79 uint16_t l2cap_next_local_cid(void){ 80 return source_cid++; 81 } 82 83 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){ 84 85 int pb = hci_non_flushable_packet_boundary_flag_supported() ? 0x00 : 0x02; 86 87 // 0 - Connection handle : PB=pb : BC=00 88 bt_store_16(acl_buffer, 0, handle | (pb << 12) | (0 << 14)); 89 // 6 - L2CAP channel = 1 90 bt_store_16(acl_buffer, 6, cid); 91 // 8 - Code 92 acl_buffer[8] = cmd; 93 // 9 - id (!= 0 sequentially) 94 acl_buffer[9] = identifier; 95 96 // 12 - L2CAP signaling parameters 97 uint16_t pos = 12; 98 // skip AMP commands 99 if (cmd >= CONNECTION_PARAMETER_UPDATE_REQUEST){ 100 cmd -= 6; 101 } 102 const char *format = l2cap_signaling_commands_format[cmd-1]; 103 uint16_t word; 104 uint8_t * ptr; 105 while (*format) { 106 switch(*format) { 107 case '1': // 8 bit value 108 case '2': // 16 bit value 109 word = va_arg(argptr, int); 110 // minimal va_arg is int: 2 bytes on 8+16 bit CPUs 111 acl_buffer[pos++] = word & 0xff; 112 if (*format == '2') { 113 acl_buffer[pos++] = word >> 8; 114 } 115 break; 116 case 'D': // variable data. passed: len, ptr 117 word = va_arg(argptr, int); 118 ptr = va_arg(argptr, uint8_t *); 119 memcpy(&acl_buffer[pos], ptr, word); 120 pos += word; 121 break; 122 default: 123 break; 124 } 125 format++; 126 }; 127 va_end(argptr); 128 129 // Fill in various length fields: it's the number of bytes following for ACL lenght and l2cap parameter length 130 // - the l2cap payload length is counted after the following channel id (only payload) 131 132 // 2 - ACL length 133 bt_store_16(acl_buffer, 2, pos - 4); 134 // 4 - L2CAP packet length 135 bt_store_16(acl_buffer, 4, pos - 6 - 2); 136 // 10 - L2CAP signaling parameter length 137 bt_store_16(acl_buffer, 10, pos - 12); 138 139 return pos; 140 } 141 142 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){ 143 return l2cap_create_signaling_internal(acl_buffer, handle, 1, cmd, identifier, argptr); 144 } 145 146 #ifdef HAVE_BLE 147 148 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){ 149 return l2cap_create_signaling_internal(acl_buffer, handle, 5, cmd, identifier, argptr); 150 } 151 152 uint16_t l2cap_le_create_connection_parameter_update_request(uint8_t * acl_buffer, uint16_t handle, uint16_t interval_min, uint16_t interval_max, uint16_t slave_latency, uint16_t timeout_multiplier){ 153 154 int pb = hci_non_flushable_packet_boundary_flag_supported() ? 0x00 : 0x02; 155 156 // 0 - Connection handle : PB=pb : BC=00 157 bt_store_16(acl_buffer, 0, handle | (pb << 12) | (0 << 14)); 158 // 6 - L2CAP LE Signaling channel = 5 159 bt_store_16(acl_buffer, 6, 5); 160 // 8 - Code 161 acl_buffer[8] = CONNECTION_PARAMETER_UPDATE_REQUEST; 162 // 9 - id (!= 0 sequentially) 163 acl_buffer[9] = 1; 164 uint16_t pos = 12; 165 bt_store_16(acl_buffer, pos, interval_min); 166 pos += 2; 167 bt_store_16(acl_buffer, pos, interval_max); 168 pos += 2; 169 bt_store_16(acl_buffer, pos, slave_latency); 170 pos += 2; 171 bt_store_16(acl_buffer, pos, timeout_multiplier); 172 pos += 2; 173 // 2 - ACL length 174 bt_store_16(acl_buffer, 2, pos - 4); 175 // 4 - L2CAP packet length 176 bt_store_16(acl_buffer, 4, pos - 6 - 2); 177 // 10 - L2CAP signaling parameter length 178 bt_store_16(acl_buffer, 10, pos - 12); 179 return pos; 180 } 181 #endif 182