xref: /btstack/platform/wiced/btstack_link_key_db_wiced_dct.c (revision 0561b2d8d5dba972c7daa57d5e677f7a1327edfd) 
1 /*
2  * Copyright (C) 2016 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__ "btstack_link_key_db_wiced_dct.c"
39 
40 /*
41  *  btstack_link_key_db_wiced_dct.c
42  *
43  *  Persistent Link Key implemenetation for WICED using DCT mechanism
44  */
45 
46 #include "classic/btstack_link_key_db.h"
47 
48 #include "stdint.h"
49 #include "string.h"
50 #include "btstack_debug.h"
51 #include "btstack_util.h"
52 
53 #include "wiced.h"
54 
55 // Link Key Magic
56 #define LINK_KEY_MAGIC ((uint32_t) 'B' << 24 | 'T' << 16 | 'L' << 8 | 'K')
57 
58 typedef struct link_key_nvm {
59 	uint32_t magic;
60 	uint32_t seq_nr;	// used for "last recently stored" eviction strategy
61 	bd_addr_t bd_addr;
62 	link_key_t link_key;
63 	link_key_type_t link_key_type;
64 } link_key_nvm_t;
65 
66 static char link_key_to_str_buffer[LINK_KEY_STR_LEN+1];  // 11223344556677889900112233445566\0
67 static char *link_key_to_str(link_key_t link_key){
68     char * p = link_key_to_str_buffer;
69     int i;
70     for (i = 0; i < LINK_KEY_LEN ; i++) {
71         *p++ = char_for_nibble((link_key[i] >> 4) & 0x0F);
72         *p++ = char_for_nibble((link_key[i] >> 0) & 0x0F);
73     }
74     *p = 0;
75     return (char *) link_key_to_str_buffer;
76 }
77 
78 static void link_key_db_init(void){
79 	log_info("Link Key DB initialized for DCT\n");
80 }
81 
82 static void link_key_db_close(void){
83 }
84 
85 // @return valid
86 static int link_key_read(int index, link_key_nvm_t * out_entry){
87 
88 	// calculate address
89 	uint32_t address = index * sizeof(link_key_nvm_t);
90 
91 	// read lock
92 	link_key_nvm_t * entry;
93 	wiced_dct_read_lock((void*) &entry, WICED_FALSE, DCT_APP_SECTION, address, sizeof(link_key_nvm_t));
94 
95 	if (entry->magic == LINK_KEY_MAGIC){
96 		memcpy(out_entry, entry, sizeof(link_key_nvm_t));
97 	} else {
98 		memset(out_entry, 0, sizeof(link_key_nvm_t));
99 	}
100 
101 	// read unlock
102 	wiced_dct_read_unlock((void*) entry, WICED_FALSE);
103 
104 	return out_entry->magic == LINK_KEY_MAGIC;
105 }
106 
107 static void link_key_write(int index, link_key_nvm_t * entry){
108 	// calculate address
109 	uint32_t address = index * sizeof(link_key_nvm_t);
110 	// write block
111 	wiced_dct_write((void*)entry, DCT_APP_SECTION, address, sizeof(link_key_nvm_t));
112 }
113 
114 // returns entry index or -1
115 static int link_key_find_entry_for_address(bd_addr_t address){
116 	link_key_nvm_t item;
117 	int i;
118 	for (i=0;i<NVM_NUM_LINK_KEYS;i++){
119 		link_key_read(i, &item);
120 		if (item.magic != LINK_KEY_MAGIC) continue;
121 		if (memcmp(address, &item.bd_addr, 6) != 0) continue;
122 		return i;
123 	}
124 	return -1;
125 }
126 
127 // returns index
128 static int link_key_find_free_entry(void){
129 	link_key_nvm_t item;
130 	int i;
131 	uint32_t seq_nr = 0;
132 	int lowest_index = -1;
133 	for (i=0;i<NVM_NUM_LINK_KEYS;i++){
134 		link_key_read(i, &item);
135 		if (item.magic != LINK_KEY_MAGIC) return i;
136 		if ((lowest_index < 0) || (item.seq_nr < seq_nr)){
137 			lowest_index = i;
138 			seq_nr= item.seq_nr;
139 		}
140 	}
141 	return lowest_index;
142 }
143 
144 static uint32_t link_key_highest_seq_nr(void){
145 	link_key_nvm_t item;
146 	int i;
147 	uint32_t seq_nr = 0;
148 	for (i=0;i<NVM_NUM_LINK_KEYS;i++){
149 		link_key_read(i, &item);
150 		if (item.magic != LINK_KEY_MAGIC) continue;
151 		if (item.seq_nr < seq_nr) continue;
152 		seq_nr = item.seq_nr;
153 	}
154 	return seq_nr;
155 }
156 
157 // returns 1 if found
158 static int link_key_db_get_link_key(bd_addr_t bd_addr, link_key_t link_key, link_key_type_t * link_key_type) {
159 	int index = link_key_find_entry_for_address(bd_addr);
160 	if (index < 0) {
161 		log_info("link_key_db_get_link_key for %s -> not found\n", bd_addr_to_str(bd_addr));
162 		return 0;
163 	}
164 	link_key_nvm_t item;
165 	link_key_read(index, &item);
166 	memcpy(link_key, item.link_key, LINK_KEY_LEN);
167 	if (link_key_type) {
168 		*link_key_type = item.link_key_type;
169 	}
170 	log_info("link_key_db_get_link_key for %s -> found %s\n", bd_addr_to_str(bd_addr), link_key_to_str(link_key));
171 	return 1;
172 }
173 
174 static void link_key_db_delete_link_key(bd_addr_t bd_addr){
175 	int index = link_key_find_entry_for_address(bd_addr);
176 	if (index < 0) return;
177 
178 	link_key_nvm_t item;
179 	memset(&item, 0, sizeof(item));
180 	link_key_write(index, &item);
181 }
182 
183 
184 static void link_key_db_put_link_key(bd_addr_t bd_addr, link_key_t link_key, link_key_type_t link_key_type){
185 	// check for existing record
186 	int index = link_key_find_entry_for_address(bd_addr);
187 
188 	// if not found, use new entry
189 	if (index < 0) {
190 		index = link_key_find_free_entry();
191 	}
192 
193 	log_info("link_key_db_put_link_key for %s - key %s - at index %u\n", bd_addr_to_str(bd_addr),  link_key_to_str(link_key), index);
194 
195 	link_key_nvm_t item;
196 	item.magic = LINK_KEY_MAGIC;
197 	item.seq_nr = link_key_highest_seq_nr() + 1;
198 	memcpy(item.bd_addr, bd_addr, sizeof(bd_addr_t));
199 	memcpy(item.link_key, link_key, LINK_KEY_LEN);
200 	item.link_key_type = link_key_type;
201 	link_key_write(index, &item);
202 }
203 
204 static void link_key_db_set_local_bd_addr(bd_addr_t bd_addr){
205 }
206 
207 static int link_key_db_tlv_iterator_init(btstack_link_key_iterator_t * it){
208     it->context = (void*) 0;
209     return 1;
210 }
211 
212 static int  link_key_db_tlv_iterator_get_next(btstack_link_key_iterator_t * it, bd_addr_t bd_addr, link_key_t link_key, link_key_type_t * link_key_type){
213     uintptr_t i = (uintptr_t) it->context;
214     int found = 0;
215     while (i<NVM_NUM_LINK_KEYS){
216 		link_key_nvm_t item;
217 		link_key_read(i++, &item);
218 		if (item.magic != LINK_KEY_MAGIC) continue;
219 
220         memcpy(bd_addr, item.bd_addr, 6);
221         memcpy(link_key, item.link_key, 16);
222         *link_key_type = item.link_key_type;
223         found = 1;
224         break;
225     }
226     it->context = (void*) i;
227     return found;
228 }
229 
230 static void link_key_db_tlv_iterator_done(btstack_link_key_iterator_t * it){
231     UNUSED(it);
232 }
233 
234 const btstack_link_key_db_t btstack_link_key_db_wiced_dct = {
235     link_key_db_init,
236     link_key_db_set_local_bd_addr,
237     link_key_db_close,
238     link_key_db_get_link_key,
239     link_key_db_put_link_key,
240     link_key_db_delete_link_key,
241     link_key_db_tlv_iterator_init,
242     link_key_db_tlv_iterator_get_next,
243     link_key_db_tlv_iterator_done,
244 };
245 
246 // custom function
247 void btstack_link_key_db_wiced_dct_delete_all(void){
248 	int i;
249 	link_key_nvm_t entry;
250 	memset(&entry, 0, sizeof(link_key_nvm_t));
251 	for (i=0;i<NVM_NUM_LINK_KEYS;i++){
252 		link_key_write(i, &entry);
253 	}
254 }
255 
256 int btstack_link_key_db_wiced_dct_get_storage_size(void){
257 	return NVM_NUM_LINK_KEYS * sizeof(link_key_nvm_t);
258 }
259 
260 const btstack_link_key_db_t * btstack_link_key_db_wiced_dct_instance(void){
261     return &btstack_link_key_db_wiced_dct;
262 }
263