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 #include "hci.h" 46 47 #include <string.h> 48 49 static const char *l2cap_signaling_commands_format[] = { 50 "2D", // 0x01 command reject: reason {cmd not understood (0), sig MTU exceeded (2:max sig MTU), invalid CID (4:req CID)}, data len, data 51 "22", // 0x02 connection request: PSM, Source CID 52 "2222", // 0x03 connection response: Dest CID, Source CID, Result, Status 53 "22D", // 0x04 config request: Dest CID, Flags, Configuration options 54 "222D", // 0x05 config response: Source CID, Flags, Result, Configuration options 55 "22", // 0x06 disconection request: Dest CID, Source CID 56 "22", // 0x07 disconection response: Dest CID, Source CID 57 "D", // 0x08 echo request: Data 58 "D", // 0x09 echo response: Data 59 "2", // 0x0a information request: InfoType {1=Connectionless MTU, 2=Extended features supported} 60 "22D", // 0x0b information response: InfoType, Result, Data 61 #ifdef HAVE_BLE 62 // skip 6 not supported signaling pdus, see below 63 "2222", // 0x12 connection parameter update request: interval min, interval max, slave latency, timeout multipler 64 "2", // 0x13 connection parameter update response: result 65 #endif 66 }; 67 68 uint8_t sig_seq_nr = 0xff; 69 uint16_t source_cid = 0x40; 70 71 uint8_t l2cap_next_sig_id(void){ 72 if (sig_seq_nr == 0xff) { 73 sig_seq_nr = 1; 74 } else { 75 sig_seq_nr++; 76 } 77 return sig_seq_nr; 78 } 79 80 uint16_t l2cap_next_local_cid(void){ 81 return source_cid++; 82 } 83 84 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){ 85 86 int pb = hci_non_flushable_packet_boundary_flag_supported() ? 0x00 : 0x02; 87 88 // 0 - Connection handle : PB=pb : BC=00 89 bt_store_16(acl_buffer, 0, handle | (pb << 12) | (0 << 14)); 90 // 6 - L2CAP channel = 1 91 bt_store_16(acl_buffer, 6, cid); 92 // 8 - Code 93 acl_buffer[8] = cmd; 94 // 9 - id (!= 0 sequentially) 95 acl_buffer[9] = identifier; 96 97 // 12 - L2CAP signaling parameters 98 uint16_t pos = 12; 99 // skip AMP commands 100 if (cmd >= CONNECTION_PARAMETER_UPDATE_REQUEST){ 101 cmd -= 6; 102 } 103 const char *format = l2cap_signaling_commands_format[cmd-1]; 104 uint16_t word; 105 uint8_t * ptr; 106 while (*format) { 107 switch(*format) { 108 case '1': // 8 bit value 109 case '2': // 16 bit value 110 word = va_arg(argptr, int); 111 // minimal va_arg is int: 2 bytes on 8+16 bit CPUs 112 acl_buffer[pos++] = word & 0xff; 113 if (*format == '2') { 114 acl_buffer[pos++] = word >> 8; 115 } 116 break; 117 case 'D': // variable data. passed: len, ptr 118 word = va_arg(argptr, int); 119 ptr = va_arg(argptr, uint8_t *); 120 memcpy(&acl_buffer[pos], ptr, word); 121 pos += word; 122 break; 123 default: 124 break; 125 } 126 format++; 127 }; 128 va_end(argptr); 129 130 // Fill in various length fields: it's the number of bytes following for ACL lenght and l2cap parameter length 131 // - the l2cap payload length is counted after the following channel id (only payload) 132 133 // 2 - ACL length 134 bt_store_16(acl_buffer, 2, pos - 4); 135 // 4 - L2CAP packet length 136 bt_store_16(acl_buffer, 4, pos - 6 - 2); 137 // 10 - L2CAP signaling parameter length 138 bt_store_16(acl_buffer, 10, pos - 12); 139 140 return pos; 141 } 142 143 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){ 144 return l2cap_create_signaling_internal(acl_buffer, handle, 1, cmd, identifier, argptr); 145 } 146 147 #ifdef HAVE_BLE 148 149 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){ 150 return l2cap_create_signaling_internal(acl_buffer, handle, 5, cmd, identifier, argptr); 151 } 152 153 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){ 154 155 int pb = hci_non_flushable_packet_boundary_flag_supported() ? 0x00 : 0x02; 156 157 // 0 - Connection handle : PB=pb : BC=00 158 bt_store_16(acl_buffer, 0, handle | (pb << 12) | (0 << 14)); 159 // 6 - L2CAP LE Signaling channel = 5 160 bt_store_16(acl_buffer, 6, 5); 161 // 8 - Code 162 acl_buffer[8] = CONNECTION_PARAMETER_UPDATE_REQUEST; 163 // 9 - id (!= 0 sequentially) 164 acl_buffer[9] = 1; 165 uint16_t pos = 12; 166 bt_store_16(acl_buffer, pos, interval_min); 167 pos += 2; 168 bt_store_16(acl_buffer, pos, interval_max); 169 pos += 2; 170 bt_store_16(acl_buffer, pos, slave_latency); 171 pos += 2; 172 bt_store_16(acl_buffer, pos, timeout_multiplier); 173 pos += 2; 174 // 2 - ACL length 175 bt_store_16(acl_buffer, 2, pos - 4); 176 // 4 - L2CAP packet length 177 bt_store_16(acl_buffer, 4, pos - 6 - 2); 178 // 10 - L2CAP signaling parameter length 179 bt_store_16(acl_buffer, 10, pos - 12); 180 return pos; 181 } 182 183 uint16_t l2cap_le_create_connection_parameter_update_response(uint8_t * acl_buffer, uint16_t handle, uint16_t response){ 184 185 int pb = hci_non_flushable_packet_boundary_flag_supported() ? 0x00 : 0x02; 186 187 // 0 - Connection handle : PB=pb : BC=00 188 bt_store_16(acl_buffer, 0, handle | (pb << 12) | (0 << 14)); 189 // 6 - L2CAP LE Signaling channel = 5 190 bt_store_16(acl_buffer, 6, 5); 191 // 8 - Code 192 acl_buffer[8] = CONNECTION_PARAMETER_UPDATE_REQUEST; 193 // 9 - id (!= 0 sequentially) 194 acl_buffer[9] = 1; 195 uint16_t pos = 12; 196 bt_store_16(acl_buffer, pos, response); 197 pos += 2; 198 // 2 - ACL length 199 bt_store_16(acl_buffer, 2, pos - 4); 200 // 4 - L2CAP packet length 201 bt_store_16(acl_buffer, 4, pos - 6 - 2); 202 // 10 - L2CAP signaling parameter length 203 bt_store_16(acl_buffer, 10, pos - 12); 204 return pos; 205 } 206 207 208 #endif 209