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 BLUEKITCHEN 24 * GMBH 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__ "sm_pairing_central.c" 39 40 41 // ***************************************************************************** 42 /* EXAMPLE_START(sm_pairing_central): LE Central - Test Pairing Methods 43 * 44 * @text Depending on the Authentication requiremens and IO Capabilities, 45 * the pairing process uses different short and long term key generation method. 46 * This example helps explore the different options incl. LE Secure Connections. 47 * It scans for advertisements and connects to the first device that lists a 48 * random service. 49 */ 50 // ***************************************************************************** 51 52 53 #include <stdint.h> 54 #include <inttypes.h> 55 #include <stdio.h> 56 #include <stdlib.h> 57 #include <string.h> 58 59 #include "btstack.h" 60 // sm_pairing_central.gatt contains the declaration of the provided GATT Services + Characteristics 61 // sm_pairing_central.h contains the binary representation of sm_pairing_central.gatt 62 // it is generated by the build system by calling: $BTSTACK_ROOT/tool/compile_gatt.py sm_pairing_central.gatt sm_pairing_central.h 63 // it needs to be regenerated when the GATT Database declared in sm_pairing_central.gatt file is modified 64 #include "sm_pairing_central.h" 65 66 67 // We're looking for a remote device that lists this service in the advertisement 68 // LightBlue assigns 0x1111 as the UUID for a Blank service. 69 #define REMOTE_SERVICE 0x1111 70 71 // Fixed passkey - used with sm_pairing_peripheral. Passkey is random in general 72 #define FIXED_PASSKEY 123456U 73 74 75 static btstack_packet_callback_registration_t hci_event_callback_registration; 76 static btstack_packet_callback_registration_t sm_event_callback_registration; 77 78 /* @section GAP LE setup for receiving advertisements 79 * 80 * @text GAP LE advertisements are received as custom HCI events of the 81 * GAP_EVENT_ADVERTISING_REPORT type. To receive them, you'll need to register 82 * the HCI packet handler, as shown in Listing GAPLEAdvSetup. 83 */ 84 85 /* LISTING_START(GAPLEAdvSetup): Setting up GAP LE client for receiving advertisements */ 86 static void hci_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size); 87 static void sm_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size); 88 89 static void sm_pairing_central_setup(void){ 90 l2cap_init(); 91 92 // setup SM: Display only 93 sm_init(); 94 95 // setup ATT server 96 att_server_init(profile_data, NULL, NULL); 97 98 // setup GATT Client 99 gatt_client_init(); 100 101 // register handler 102 hci_event_callback_registration.callback = &hci_packet_handler; 103 hci_add_event_handler(&hci_event_callback_registration); 104 105 sm_event_callback_registration.callback = &sm_packet_handler; 106 sm_add_event_handler(&sm_event_callback_registration); 107 108 109 // Configuration 110 111 // Enable mandatory authentication for GATT Client 112 // - if un-encrypted connections are not supported, e.g. when connecting to own device, this enforces authentication 113 // gatt_client_set_required_security_level(LEVEL_2); 114 115 /** 116 * Choose ONE of the following configurations 117 * Bonding is disabled to allow for repeated testing. It can be enabled by or'ing 118 * SM_AUTHREQ_BONDING to the authentication requirements like this: 119 * sm_set_authentication_requirements( X | SM_AUTHREQ_BONDING) 120 */ 121 122 // LE Legacy Pairing, Just Works 123 // sm_set_io_capabilities(IO_CAPABILITY_DISPLAY_YES_NO); 124 // sm_set_authentication_requirements(0); 125 126 // LE Legacy Pairing, Passkey entry initiator enter, responder (us) displays 127 // sm_set_io_capabilities(IO_CAPABILITY_DISPLAY_ONLY); 128 // sm_set_authentication_requirements(SM_AUTHREQ_MITM_PROTECTION); 129 // sm_use_fixed_passkey_in_display_role(FIXED_PASSKEY); 130 131 #ifdef ENABLE_LE_SECURE_CONNECTIONS 132 133 // enable LE Secure Connections Only mode - disables Legacy pairing 134 // sm_set_secure_connections_only_mode(true); 135 136 // LE Secure Connections, Just Works 137 // sm_set_io_capabilities(IO_CAPABILITY_DISPLAY_YES_NO); 138 // sm_set_authentication_requirements(SM_AUTHREQ_SECURE_CONNECTION); 139 140 // LE Secure Connections, Numeric Comparison 141 // sm_set_io_capabilities(IO_CAPABILITY_DISPLAY_YES_NO); 142 // sm_set_authentication_requirements(SM_AUTHREQ_SECURE_CONNECTION|SM_AUTHREQ_MITM_PROTECTION); 143 144 // LE Secure Pairing, Passkey entry initiator (us) enters, responder displays 145 // sm_set_io_capabilities(IO_CAPABILITY_KEYBOARD_ONLY); 146 // sm_set_authentication_requirements(SM_AUTHREQ_SECURE_CONNECTION|SM_AUTHREQ_MITM_PROTECTION); 147 // sm_use_fixed_passkey_in_display_role(FIXED_PASSKEY); 148 149 // LE Secure Pairing, Passkey entry initiator (us) displays, responder enters 150 // sm_set_io_capabilities(IO_CAPABILITY_DISPLAY_ONLY); 151 // sm_set_authentication_requirements(SM_AUTHREQ_SECURE_CONNECTION|SM_AUTHREQ_MITM_PROTECTION); 152 #endif 153 } 154 155 /* LISTING_END */ 156 157 /* @section HCI packet handler 158 * 159 * @text The HCI packet handler has to start the scanning, 160 * and to handle received advertisements. Advertisements are received 161 * as HCI event packets of the GAP_EVENT_ADVERTISING_REPORT type, 162 * see Listing HCIPacketHandler. 163 */ 164 165 /* LISTING_START(HCIPacketHandler): Scanning and receiving advertisements */ 166 167 static void hci_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 168 UNUSED(channel); 169 UNUSED(size); 170 171 if (packet_type != HCI_EVENT_PACKET) return; 172 hci_con_handle_t con_handle; 173 uint8_t status; 174 175 switch (hci_event_packet_get_type(packet)) { 176 case BTSTACK_EVENT_STATE: 177 // BTstack activated, get started 178 if (btstack_event_state_get_state(packet) == HCI_STATE_WORKING){ 179 printf("Start scaning!\n"); 180 gap_set_scan_parameters(1,0x0030, 0x0030); 181 gap_start_scan(); 182 } 183 break; 184 case GAP_EVENT_ADVERTISING_REPORT:{ 185 bd_addr_t address; 186 gap_event_advertising_report_get_address(packet, address); 187 uint8_t address_type = gap_event_advertising_report_get_address_type(packet); 188 uint8_t length = gap_event_advertising_report_get_data_length(packet); 189 const uint8_t * data = gap_event_advertising_report_get_data(packet); 190 // printf("Advertisement event: addr-type %u, addr %s, data[%u] ", 191 // address_type, bd_addr_to_str(address), length); 192 // printf_hexdump(data, length); 193 if (!ad_data_contains_uuid16(length, (uint8_t *) data, REMOTE_SERVICE)) break; 194 printf("Found remote with UUID %04x, connecting...\n", REMOTE_SERVICE); 195 gap_stop_scan(); 196 gap_connect(address,address_type); 197 break; 198 } 199 case HCI_EVENT_LE_META: 200 // wait for connection complete 201 if (hci_event_le_meta_get_subevent_code(packet) != HCI_SUBEVENT_LE_CONNECTION_COMPLETE) break; 202 con_handle = hci_subevent_le_connection_complete_get_connection_handle(packet); 203 printf("Connection complete\n"); 204 205 // for testing, choose one of the following actions 206 207 // manually start pairing 208 sm_request_pairing(con_handle); 209 210 // gatt client request to authenticated characteristic in sm_pairing_peripheral (short cut, uses hard-coded value handle) 211 // gatt_client_read_value_of_characteristic_using_value_handle(&hci_packet_handler, con_handle, 0x0009); 212 213 // general gatt client request to trigger mandatory authentication 214 // gatt_client_discover_primary_services(&hci_packet_handler, con_handle); 215 break; 216 case HCI_EVENT_ENCRYPTION_CHANGE: 217 con_handle = hci_event_encryption_change_get_connection_handle(packet); 218 printf("Connection encrypted: %u\n", hci_event_encryption_change_get_encryption_enabled(packet)); 219 break; 220 case GATT_EVENT_QUERY_COMPLETE: 221 status = gatt_event_query_complete_get_att_status(packet); 222 switch (status){ 223 case ATT_ERROR_INSUFFICIENT_ENCRYPTION: 224 printf("GATT Query result: Insufficient Encryption\n"); 225 break; 226 case ATT_ERROR_INSUFFICIENT_AUTHENTICATION: 227 printf("GATT Query result: Insufficient Authentication\n"); 228 break; 229 case ATT_ERROR_BONDING_INFORMATION_MISSING: 230 printf("GATT Query result: Bonding Information Missing\n"); 231 break; 232 case ATT_ERROR_SUCCESS: 233 printf("GATT Query result: OK\n"); 234 break; 235 default: 236 printf("GATT Query result: 0x%02x\n", gatt_event_query_complete_get_att_status(packet)); 237 break; 238 } 239 break; 240 default: 241 break; 242 } 243 } 244 245 /* @section HCI packet handler 246 * 247 * @text The SM packet handler receives Security Manager Events required for pairing. 248 * It also receives events generated during Identity Resolving 249 * see Listing SMPacketHandler. 250 */ 251 252 /* LISTING_START(SMPacketHandler): Scanning and receiving advertisements */ 253 254 static void sm_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){ 255 UNUSED(channel); 256 UNUSED(size); 257 258 if (packet_type != HCI_EVENT_PACKET) return; 259 260 bd_addr_t addr; 261 bd_addr_type_t addr_type; 262 263 switch (hci_event_packet_get_type(packet)) { 264 case SM_EVENT_JUST_WORKS_REQUEST: 265 printf("Just works requested\n"); 266 sm_just_works_confirm(sm_event_just_works_request_get_handle(packet)); 267 break; 268 case SM_EVENT_NUMERIC_COMPARISON_REQUEST: 269 printf("Confirming numeric comparison: %"PRIu32"\n", sm_event_numeric_comparison_request_get_passkey(packet)); 270 sm_numeric_comparison_confirm(sm_event_passkey_display_number_get_handle(packet)); 271 break; 272 case SM_EVENT_PASSKEY_DISPLAY_NUMBER: 273 printf("Display Passkey: %"PRIu32"\n", sm_event_passkey_display_number_get_passkey(packet)); 274 break; 275 case SM_EVENT_PASSKEY_INPUT_NUMBER: 276 printf("Passkey Input requested\n"); 277 printf("Sending fixed passkey %"PRIu32"\n", (uint32_t) FIXED_PASSKEY); 278 sm_passkey_input(sm_event_passkey_input_number_get_handle(packet), FIXED_PASSKEY); 279 break; 280 case SM_EVENT_PAIRING_STARTED: 281 printf("Pairing started\n"); 282 break; 283 case SM_EVENT_PAIRING_COMPLETE: 284 switch (sm_event_pairing_complete_get_status(packet)){ 285 case ERROR_CODE_SUCCESS: 286 printf("Pairing complete, success\n"); 287 break; 288 case ERROR_CODE_CONNECTION_TIMEOUT: 289 printf("Pairing failed, timeout\n"); 290 break; 291 case ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION: 292 printf("Pairing failed, disconnected\n"); 293 break; 294 case ERROR_CODE_AUTHENTICATION_FAILURE: 295 printf("Pairing failed, authentication failure with reason = %u\n", sm_event_pairing_complete_get_reason(packet)); 296 break; 297 default: 298 break; 299 } 300 break; 301 case SM_EVENT_REENCRYPTION_STARTED: 302 sm_event_reencryption_complete_get_address(packet, addr); 303 printf("Bonding information exists for addr type %u, identity addr %s -> start re-encryption\n", 304 sm_event_reencryption_started_get_addr_type(packet), bd_addr_to_str(addr)); 305 break; 306 case SM_EVENT_REENCRYPTION_COMPLETE: 307 switch (sm_event_reencryption_complete_get_status(packet)){ 308 case ERROR_CODE_SUCCESS: 309 printf("Re-encryption complete, success\n"); 310 break; 311 case ERROR_CODE_CONNECTION_TIMEOUT: 312 printf("Re-encryption failed, timeout\n"); 313 break; 314 case ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION: 315 printf("Re-encryption failed, disconnected\n"); 316 break; 317 case ERROR_CODE_PIN_OR_KEY_MISSING: 318 printf("Re-encryption failed, bonding information missing\n\n"); 319 printf("Assuming remote lost bonding information\n"); 320 printf("Deleting local bonding information and start new pairing...\n"); 321 sm_event_reencryption_complete_get_address(packet, addr); 322 addr_type = sm_event_reencryption_started_get_addr_type(packet); 323 gap_delete_bonding(addr_type, addr); 324 sm_request_pairing(sm_event_reencryption_complete_get_handle(packet)); 325 break; 326 default: 327 break; 328 } 329 break; 330 default: 331 break; 332 } 333 } 334 /* LISTING_END */ 335 336 int btstack_main(void); 337 int btstack_main(void) 338 { 339 sm_pairing_central_setup(); 340 341 // turn on! 342 hci_power_control(HCI_POWER_ON); 343 344 return 0; 345 } 346 347 /* EXAMPLE_END */ 348