xref: /btstack/example/sm_pairing_central.c (revision 98c0024dfc4d2d00acd13095a6ee1ad14ba3c6a7)
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__ "sm_pairing_central.c"
39 
40 
41 // *****************************************************************************
42 /* EXAMPLE_START(sm_pairing_central): LE Peripheral - Test pairing combinations
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 #include "sm_pairing_central.h"
61 
62 
63 // We're looking for a remote device that lists this service in the advertisement
64 // LightBlue assigns 0x1111 as the UUID for a Blank service.
65 #define REMOTE_SERVICE 0x1111
66 
67 // Fixed passkey - used with sm_pairing_peripheral. Passkey is random in general
68 #define FIXED_PASSKEY 12346
69 
70 
71 static btstack_packet_callback_registration_t hci_event_callback_registration;
72 static btstack_packet_callback_registration_t sm_event_callback_registration;
73 
74 /* @section GAP LE setup for receiving advertisements
75  *
76  * @text GAP LE advertisements are received as custom HCI events of the
77  * GAP_EVENT_ADVERTISING_REPORT type. To receive them, you'll need to register
78  * the HCI packet handler, as shown in Listing GAPLEAdvSetup.
79  */
80 
81 /* LISTING_START(GAPLEAdvSetup): Setting up GAP LE client for receiving advertisements */
82 static void hci_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
83 static void sm_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
84 
85 static void sm_pairing_central_setup(void){
86     l2cap_init();
87 
88     // setup le device db
89     le_device_db_init();
90 
91     // setup SM: Display only
92     sm_init();
93 
94     // setup ATT server
95     att_server_init(profile_data, NULL, NULL);
96 
97     /**
98      * Choose ONE of the following configurations
99      * Bonding is disabled to allow for repeated testing. It can be enabled with SM_AUTHREQ_BONDING
100      */
101 
102     // register handler
103     hci_event_callback_registration.callback = &hci_packet_handler;
104     hci_add_event_handler(&hci_event_callback_registration);
105 
106     sm_event_callback_registration.callback = &sm_packet_handler;
107     sm_add_event_handler(&sm_event_callback_registration);
108 
109     // LE Legacy Pairing, Just Works
110     // sm_set_io_capabilities(IO_CAPABILITY_DISPLAY_YES_NO);
111     // sm_set_authentication_requirements(SM_AUTHREQ_ NO_BONDING);
112 
113     // LE Legacy Pairing, Passkey entry initiator enter, responder (us) displays
114     // sm_set_io_capabilities(IO_CAPABILITY_DISPLAY_ONLY);
115     // sm_set_authentication_requirements(SM_AUTHREQ_MITM_PROTECTION);
116     // sm_use_fixed_passkey_in_display_role(FIXED_PASSKEY);
117 
118 #ifdef ENABLE_LE_SECURE_CONNECTIONS
119     // LE Secure Connetions, Just Works
120     // sm_set_io_capabilities(IO_CAPABILITY_DISPLAY_YES_NO);
121     // sm_set_authentication_requirements(SM_AUTHREQ_SECURE_CONNECTION);
122 
123     // LE Secure Connections, Numeric Comparison
124     // sm_set_io_capabilities(IO_CAPABILITY_KEYBOARD_ONLY);
125     sm_set_io_capabilities(IO_CAPABILITY_DISPLAY_YES_NO);
126     sm_set_authentication_requirements(SM_AUTHREQ_SECURE_CONNECTION|SM_AUTHREQ_MITM_PROTECTION);
127 
128     // LE Legacy Pairing, Passkey entry initiator enter, responder (us) displays
129     // sm_set_io_capabilities(IO_CAPABILITY_DISPLAY_ONLY);
130     // sm_set_authentication_requirements(SM_AUTHREQ_SECURE_CONNECTION|SM_AUTHREQ_MITM_PROTECTION);
131     // sm_use_fixed_passkey_in_display_role(FIXED_PASSKEY);
132 #endif
133 }
134 
135 /* LISTING_END */
136 
137 /* @section HCI packet handler
138  *
139  * @text The HCI packet handler has to start the scanning,
140  * and to handle received advertisements. Advertisements are received
141  * as HCI event packets of the GAP_EVENT_ADVERTISING_REPORT type,
142  * see Listing HCIPacketHandler.
143  */
144 
145 /* LISTING_START(HCIPacketHandler): Scanning and receiving advertisements */
146 
147 static void hci_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
148     UNUSED(channel);
149     UNUSED(size);
150 
151     if (packet_type != HCI_EVENT_PACKET) return;
152     hci_con_handle_t con_handle;
153 
154     switch (hci_event_packet_get_type(packet)) {
155         case BTSTACK_EVENT_STATE:
156             // BTstack activated, get started
157             if (btstack_event_state_get_state(packet) == HCI_STATE_WORKING){
158                 printf("Start scaning!\n");
159                 gap_set_scan_parameters(1,0x0030, 0x0030);
160                 gap_start_scan();
161             }
162             break;
163         case GAP_EVENT_ADVERTISING_REPORT:{
164             bd_addr_t address;
165             gap_event_advertising_report_get_address(packet, address);
166             uint8_t address_type = gap_event_advertising_report_get_address_type(packet);
167             uint8_t length = gap_event_advertising_report_get_data_length(packet);
168             const uint8_t * data = gap_event_advertising_report_get_data(packet);
169             // printf("Advertisement event: addr-type %u, addr %s, data[%u] ",
170             //   address_type, bd_addr_to_str(address), length);
171             // printf_hexdump(data, length);
172             if (!ad_data_contains_uuid16(length, (uint8_t *) data, REMOTE_SERVICE)) break;
173             printf("Found remote with UUID %04x, connecting...\n", REMOTE_SERVICE);
174             gap_stop_scan();
175             gap_connect(address,address_type);
176             break;
177         }
178         case HCI_EVENT_LE_META:
179             // wait for connection complete
180             if (hci_event_le_meta_get_subevent_code(packet) != HCI_SUBEVENT_LE_CONNECTION_COMPLETE) break;
181             con_handle = hci_subevent_le_connection_complete_get_connection_handle(packet);
182             printf("Connection complete\n");
183             // start pairing
184             sm_request_pairing(con_handle);
185             break;
186         case HCI_EVENT_ENCRYPTION_CHANGE:
187             con_handle = hci_event_encryption_change_get_connection_handle(packet);
188             printf("Connection encrypted: %u\n", hci_event_encryption_change_get_encryption_enabled(packet));
189             break;
190         default:
191             break;
192     }
193 }
194 
195 /* @section HCI packet handler
196  *
197  * @text The SM packet handler receives Security Manager Events required for pairing.
198  * It also receives events generated during Identity Resolving
199  * see Listing SMPacketHandler.
200  */
201 
202 /* LISTING_START(SMPacketHandler): Scanning and receiving advertisements */
203 
204 static void sm_packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
205     UNUSED(channel);
206     UNUSED(size);
207 
208     if (packet_type != HCI_EVENT_PACKET) return;
209 
210     switch (hci_event_packet_get_type(packet)) {
211         case SM_EVENT_JUST_WORKS_REQUEST:
212             printf("Just works requested\n");
213             sm_just_works_confirm(sm_event_just_works_request_get_handle(packet));
214             break;
215         case SM_EVENT_NUMERIC_COMPARISON_REQUEST:
216             printf("Confirming numeric comparison: %"PRIu32"\n", sm_event_numeric_comparison_request_get_passkey(packet));
217             sm_numeric_comparison_confirm(sm_event_passkey_display_number_get_handle(packet));
218             break;
219         case SM_EVENT_PASSKEY_DISPLAY_NUMBER:
220             printf("Display Passkey: %"PRIu32"\n", sm_event_passkey_display_number_get_passkey(packet));
221             break;
222         case SM_EVENT_PASSKEY_INPUT_NUMBER:
223             printf("Passkey Input requested\n");
224             printf("Sending fixed passkey %"PRIu32"\n", FIXED_PASSKEY);
225             sm_passkey_input(sm_event_passkey_input_number_get_handle(packet), FIXED_PASSKEY);
226             break;
227         case SM_EVENT_PAIRING_COMPLETE:
228             switch (sm_event_pairing_complete_get_status(packet)){
229                 case ERROR_CODE_SUCCESS:
230                     printf("Pairing complete, success\n");
231                     break;
232                 case ERROR_CODE_CONNECTION_TIMEOUT:
233                     printf("Pairing failed, timeout\n");
234                     break;
235                 case ERROR_CODE_REMOTE_USER_TERMINATED_CONNECTION:
236                     printf("Pairing faileed, disconnected\n");
237                     break;
238                 case ERROR_CODE_AUTHENTICATION_FAILURE:
239                     printf("Pairing failed, reason = %u\n", sm_event_pairing_complete_get_reason(packet));
240                     break;
241                 default:
242                     break;
243             }
244             break;
245         default:
246             break;
247     }
248 }
249 /* LISTING_END */
250 
251 int btstack_main(void);
252 int btstack_main(void)
253 {
254     sm_pairing_central_setup();
255 
256     // turn on!
257     hci_power_control(HCI_POWER_ON);
258 
259     return 0;
260 }
261 
262 /* EXAMPLE_END */
263