xref: /btstack/src/ble/le_device_db_memory.c (revision 3edc84c5b6b1e23a3d103fe8ce1f6b5ad1df3498)
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 #include "ble/le_device_db.h"
39 
40 #include <stdio.h>
41 #include <string.h>
42 #include "debug.h"
43 
44 // Central Device db implemenation using static memory
45 typedef struct le_device_memory_db {
46 
47     // Identification
48     int addr_type;
49     bd_addr_t addr;
50     sm_key_t irk;
51 
52     // Stored pairing information allows to re-establish an enncrypted connection
53     // with a peripheral that doesn't have any persistent memory
54     sm_key_t ltk;
55     uint16_t ediv;
56     uint8_t  rand[8];
57     uint8_t  key_size;
58     uint8_t  authenticated;
59     uint8_t  authorized;
60 
61     // Signed Writes by remote
62     sm_key_t remote_csrk;
63     uint32_t remote_counter;
64 
65     // Signed Writes by us
66     sm_key_t local_csrk;
67     uint32_t local_counter;
68 
69 } le_device_memory_db_t;
70 
71 #define LE_DEVICE_MEMORY_SIZE 4
72 #define INVALID_ENTRY_ADDR_TYPE 0xff
73 
74 static le_device_memory_db_t le_devices[LE_DEVICE_MEMORY_SIZE];
75 
76 void le_device_db_init(void){
77     int i;
78     for (i=0;i<LE_DEVICE_MEMORY_SIZE;i++){
79         le_device_db_remove(i);
80     }
81 }
82 
83 // @returns number of device in db
84 int le_device_db_count(void){
85     int i;
86     int counter = 0;
87     for (i=0;i<LE_DEVICE_MEMORY_SIZE;i++){
88         if (le_devices[i].addr_type != INVALID_ENTRY_ADDR_TYPE) counter++;
89     }
90     return counter;
91 }
92 
93 // free device
94 void le_device_db_remove(int index){
95     le_devices[index].addr_type = INVALID_ENTRY_ADDR_TYPE;
96 }
97 
98 int le_device_db_add(int addr_type, bd_addr_t addr, sm_key_t irk){
99     int i;
100     int index = -1;
101     for (i=0;i<LE_DEVICE_MEMORY_SIZE;i++){
102          if (le_devices[i].addr_type == INVALID_ENTRY_ADDR_TYPE){
103             index = i;
104             break;
105          }
106     }
107 
108     if (index < 0) return -1;
109 
110     log_info("Central Device DB adding type %u - %s", addr_type, bd_addr_to_str(addr));
111     log_key("irk", irk);
112 
113     le_devices[index].addr_type = addr_type;
114     memcpy(le_devices[index].addr, addr, 6);
115     memcpy(le_devices[index].irk, irk, 16);
116     le_devices[index].remote_counter = 0;
117 
118     return index;
119 }
120 
121 
122 // get device information: addr type and address
123 void le_device_db_info(int index, int * addr_type, bd_addr_t addr, sm_key_t irk){
124     if (addr_type) *addr_type = le_devices[index].addr_type;
125     if (addr) memcpy(addr, le_devices[index].addr, 6);
126     if (irk) memcpy(irk, le_devices[index].irk, 16);
127 }
128 
129 void le_device_db_encryption_set(int index, uint16_t ediv, uint8_t rand[8], sm_key_t ltk, int key_size, int authenticated, int authorized){
130     log_info("Central Device DB set encryption for %u, ediv x%04x, key size %u, authenticated %u, authorized %u",
131         index, ediv, key_size, authenticated, authorized);
132     le_device_memory_db_t * device = &le_devices[index];
133     device->ediv = ediv;
134     if (rand) memcpy(device->rand, rand, 8);
135     if (ltk) memcpy(device->ltk, ltk, 16);
136     device->key_size = key_size;
137     device->authenticated = authenticated;
138     device->authorized = authorized;
139 }
140 
141 void le_device_db_encryption_get(int index, uint16_t * ediv, uint8_t rand[8], sm_key_t ltk, int * key_size, int * authenticated, int * authorized){
142     le_device_memory_db_t * device = &le_devices[index];
143     log_info("Central Device DB encryption for %u, ediv x%04x, keysize %u, authenticated %u, authorized %u",
144         index, device->ediv, device->key_size, device->authenticated, device->authorized);
145     if (ediv) *ediv = device->ediv;
146     if (rand) memcpy(rand, device->rand, 8);
147     if (ltk)  memcpy(ltk, device->ltk, 16);
148     if (key_size) *key_size = device->key_size;
149     if (authenticated) *authenticated = device->authenticated;
150     if (authorized) *authorized = device->authorized;
151 }
152 
153 // get signature key
154 void le_device_db_remote_csrk_get(int index, sm_key_t csrk){
155     if (index < 0 || index >= LE_DEVICE_MEMORY_SIZE){
156         log_error("le_device_db_remote_csrk_get called with invalid index %d", index);
157         return;
158     }
159     if (csrk) memcpy(csrk, le_devices[index].remote_csrk, 16);
160 }
161 
162 void le_device_db_remote_csrk_set(int index, sm_key_t csrk){
163     if (index < 0 || index >= LE_DEVICE_MEMORY_SIZE){
164         log_error("le_device_db_remote_csrk_set called with invalid index %d", index);
165         return;
166     }
167     if (csrk) memcpy(le_devices[index].remote_csrk, csrk, 16);
168 }
169 
170 void le_device_db_local_csrk_get(int index, sm_key_t csrk){
171     if (index < 0 || index >= LE_DEVICE_MEMORY_SIZE){
172         log_error("le_device_db_local_csrk_get called with invalid index %d", index);
173         return;
174     }
175     if (csrk) memcpy(csrk, le_devices[index].local_csrk, 16);
176 }
177 
178 void le_device_db_local_csrk_set(int index, sm_key_t csrk){
179     if (index < 0 || index >= LE_DEVICE_MEMORY_SIZE){
180         log_error("le_device_db_local_csrk_set called with invalid index %d", index);
181         return;
182     }
183     if (csrk) memcpy(le_devices[index].local_csrk, csrk, 16);
184 }
185 
186 // query last used/seen signing counter
187 uint32_t le_device_db_remote_counter_get(int index){
188     return le_devices[index].remote_counter;
189 }
190 
191 // update signing counter
192 void le_device_db_remote_counter_set(int index, uint32_t counter){
193     le_devices[index].remote_counter = counter;
194 }
195 
196 // query last used/seen signing counter
197 uint32_t le_device_db_local_counter_get(int index){
198     return le_devices[index].local_counter;
199 }
200 
201 // update signing counter
202 void le_device_db_local_counter_set(int index, uint32_t counter){
203     le_devices[index].local_counter = counter;
204 }
205 
206 void le_device_db_dump(void){
207     log_info("Central Device DB dump, devices: %d", le_device_db_count());
208     int i;
209     for (i=0;i<LE_DEVICE_MEMORY_SIZE;i++){
210         if (le_devices[i].addr_type == INVALID_ENTRY_ADDR_TYPE) continue;
211         log_info("%u: %u %s", i, le_devices[i].addr_type, bd_addr_to_str(le_devices[i].addr));
212         log_key("irk", le_devices[i].irk);
213         log_key("local csrk", le_devices[i].local_csrk);
214         log_key("remote csrk", le_devices[i].remote_csrk);
215     }
216 }
217