xref: /btstack/example/sm_pairing_central.c (revision c37cd8f3d1350b92a2f66c31b2a5fcd75f8c91a4)
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 
68 static btstack_packet_callback_registration_t hci_event_callback_registration;
69 static btstack_packet_callback_registration_t sm_event_callback_registration;
70 
71 /* @section GAP LE setup for receiving advertisements
72  *
73  * @text GAP LE advertisements are received as custom HCI events of the
74  * GAP_EVENT_ADVERTISING_REPORT type. To receive them, you'll need to register
75  * the HCI packet handler, as shown in Listing GAPLEAdvSetup.
76  */
77 
78 /* LISTING_START(GAPLEAdvSetup): Setting up GAP LE client for receiving advertisements */
79 static void packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size);
80 
81 static void sm_pairing_central_setup(void){
82     hci_event_callback_registration.callback = &packet_handler;
83     hci_add_event_handler(&hci_event_callback_registration);
84 
85     l2cap_init();
86 
87     // setup le device db
88     le_device_db_init();
89 
90     // setup SM: Display only
91     sm_init();
92     sm_event_callback_registration.callback = &packet_handler;
93     sm_add_event_handler(&sm_event_callback_registration);
94 
95     // setup ATT server
96     att_server_init(profile_data, NULL, NULL);
97     att_server_register_packet_handler(packet_handler);
98 
99     /**
100      * Choose ONE of the following configurations
101      */
102 
103     // LE Legacy Pairing, Just Works
104     sm_set_io_capabilities(IO_CAPABILITY_DISPLAY_YES_NO);
105     sm_set_authentication_requirements(SM_AUTHREQ_NO_BONDING);
106 
107     // LE Legacy Pairing, Passkey entry initiator enter, responder (us) displays
108     // sm_set_io_capabilities(IO_CAPABILITY_DISPLAY_ONLY);
109     // sm_set_authentication_requirements(SM_AUTHREQ_MITM_PROTECTION);
110     // sm_use_fixed_passkey_in_display_role(123456);
111 
112 #ifdef ENABLE_LE_SECURE_CONNECTIONS
113     // LE Secure Connetions, Just Works
114     // sm_set_io_capabilities(IO_CAPABILITY_DISPLAY_YES_NO);
115     // sm_set_authentication_requirements(SM_AUTHREQ_SECURE_CONNECTION);
116 
117     // LE Secure Connections, Numeric Comparison
118     // sm_set_io_capabilities(IO_CAPABILITY_DISPLAY_YES_NO);
119     // sm_set_authentication_requirements(SM_AUTHREQ_SECURE_CONNECTION|SM_AUTHREQ_MITM_PROTECTION);
120 
121     // LE Legacy Pairing, Passkey entry initiator enter, responder (us) displays
122     // sm_set_io_capabilities(IO_CAPABILITY_DISPLAY_ONLY);
123     // sm_set_authentication_requirements(SM_AUTHREQ_SECURE_CONNECTION|SM_AUTHREQ_MITM_PROTECTION);
124     // sm_use_fixed_passkey_in_display_role(123456);
125 #endif
126 }
127 
128 /* LISTING_END */
129 
130 /* @section HCI packet handler
131  *
132  * @text The HCI packet handler has to start the scanning,
133  * and to handle received advertisements. Advertisements are received
134  * as HCI event packets of the GAP_EVENT_ADVERTISING_REPORT type,
135  * see Listing GAPLEAdvPacketHandler.
136  */
137 
138 /* LISTING_START(GAPLEAdvPacketHandler): Scanning and receiving advertisements */
139 
140 static void packet_handler(uint8_t packet_type, uint16_t channel, uint8_t *packet, uint16_t size){
141     UNUSED(channel);
142     UNUSED(size);
143 
144     if (packet_type != HCI_EVENT_PACKET) return;
145     hci_con_handle_t con_handle;
146 
147     switch (hci_event_packet_get_type(packet)) {
148         case BTSTACK_EVENT_STATE:
149             // BTstack activated, get started
150             if (btstack_event_state_get_state(packet) == HCI_STATE_WORKING){
151                 printf("Start scaning!\n");
152                 gap_set_scan_parameters(1,0x0030, 0x0030);
153                 gap_start_scan();
154             }
155             break;
156         case GAP_EVENT_ADVERTISING_REPORT:{
157             bd_addr_t address;
158             gap_event_advertising_report_get_address(packet, address);
159             uint8_t address_type = gap_event_advertising_report_get_address_type(packet);
160             uint8_t length = gap_event_advertising_report_get_data_length(packet);
161             const uint8_t * data = gap_event_advertising_report_get_data(packet);
162             printf("Advertisement event: addr-type %u, addr %s, data[%u] ",
163                address_type, bd_addr_to_str(address), length);
164             printf_hexdump(data, length);
165             if (!ad_data_contains_uuid16(length, (uint8_t *) data, REMOTE_SERVICE)) break;
166             printf("Found remote with UUID %04x, connecting...\n", REMOTE_SERVICE);
167             gap_stop_scan();
168             gap_connect(address,address_type);
169             break;
170         }
171         case SM_EVENT_JUST_WORKS_REQUEST:
172             printf("Just works requested\n");
173             sm_just_works_confirm(sm_event_just_works_request_get_handle(packet));
174             break;
175         case SM_EVENT_NUMERIC_COMPARISON_REQUEST:
176             printf("Confirming numeric comparison: %"PRIu32"\n", sm_event_numeric_comparison_request_get_passkey(packet));
177             sm_numeric_comparison_confirm(sm_event_passkey_display_number_get_handle(packet));
178             break;
179         case SM_EVENT_PASSKEY_DISPLAY_NUMBER:
180             printf("Display Passkey: %"PRIu32"\n", sm_event_passkey_display_number_get_passkey(packet));
181             break;
182         case HCI_EVENT_LE_META:
183             // wait for connection complete
184             if (hci_event_le_meta_get_subevent_code(packet) != HCI_SUBEVENT_LE_CONNECTION_COMPLETE) break;
185             con_handle = hci_subevent_le_connection_complete_get_connection_handle(packet);
186             // start pairing
187             sm_request_pairing(con_handle);
188             break;
189         case HCI_EVENT_ENCRYPTION_CHANGE:
190             con_handle = hci_event_encryption_change_get_connection_handle(packet);
191             printf("Connection encrypted: %u\n", hci_event_encryption_change_get_encryption_enabled(packet));
192             break;
193         default:
194             break;
195     }
196 }
197 /* LISTING_END */
198 
199 int btstack_main(void);
200 int btstack_main(void)
201 {
202     sm_pairing_central_setup();
203 
204     // turn on!
205     hci_power_control(HCI_POWER_ON);
206 
207     return 0;
208 }
209 
210 /* EXAMPLE_END */
211