1 /* $NetBSD: config.c,v 1.6 2020/06/07 00:54:22 thorpej Exp $ */
2
3 /*-
4 * Copyright (c) 2006 Itronix Inc.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. The name of Itronix Inc. may not be used to endorse
16 * or promote products derived from this software without specific
17 * prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY ITRONIX INC. ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL ITRONIX INC. BE LIABLE FOR ANY
23 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
24 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
25 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
26 * ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33 __RCSID("$NetBSD: config.c,v 1.6 2020/06/07 00:54:22 thorpej Exp $");
34
35 #include <sys/time.h>
36 #include <prop/proplib.h>
37 #include <bluetooth.h>
38 #include <errno.h>
39 #include <event.h>
40 #include <fcntl.h>
41 #include <stdlib.h>
42 #include <string.h>
43 #include <syslog.h>
44 #include <unistd.h>
45
46 #include "bthcid.h"
47
48 static const char *key_file = "/var/db/bthcid.keys";
49 static const char *new_key_file = "/var/db/bthcid.keys.new";
50
51 static prop_dictionary_t
load_keys(void)52 load_keys(void)
53 {
54 prop_dictionary_t dict;
55 char *xml;
56 off_t len;
57 int fd;
58
59 fd = open(key_file, O_RDONLY, 0);
60 if (fd < 0)
61 return NULL;
62
63 len = lseek(fd, 0, SEEK_END);
64 if (len == 0) {
65 close(fd);
66 return NULL;
67 }
68
69 xml = malloc(len);
70 if (xml == NULL) {
71 close(fd);
72 return NULL;
73 }
74
75 (void)lseek(fd, 0, SEEK_SET);
76 if (read(fd, xml, len) != len) {
77 free(xml);
78 close(fd);
79 return NULL;
80 }
81
82 dict = prop_dictionary_internalize(xml);
83 free(xml);
84 close(fd);
85 return dict;
86 }
87
88 /*
89 * Look up key in keys file. We store a dictionary for each
90 * remote address, and inside that we have a data object for
91 * each local address containing the key.
92 */
93 uint8_t *
lookup_key(bdaddr_t * laddr,bdaddr_t * raddr)94 lookup_key(bdaddr_t *laddr, bdaddr_t *raddr)
95 {
96 static uint8_t key[HCI_KEY_SIZE];
97 prop_dictionary_t cfg;
98 prop_object_t obj;
99
100 cfg = load_keys();
101 if (cfg == NULL)
102 return NULL;
103
104 obj = prop_dictionary_get(cfg, bt_ntoa(laddr, NULL));
105 if (obj == NULL || prop_object_type(obj) != PROP_TYPE_DICTIONARY) {
106 prop_object_release(cfg);
107 return NULL;
108 }
109
110 obj = prop_dictionary_get(obj, bt_ntoa(raddr, NULL));
111 if (obj == NULL || prop_object_type(obj) != PROP_TYPE_DATA
112 || prop_data_size(obj) != sizeof(key)) {
113 prop_object_release(cfg);
114 return NULL;
115 }
116
117 memcpy(key, prop_data_value(obj), sizeof(key));
118 prop_object_release(cfg);
119 return key;
120 }
121
122 void
save_key(bdaddr_t * laddr,bdaddr_t * raddr,uint8_t * key)123 save_key(bdaddr_t *laddr, bdaddr_t *raddr, uint8_t *key)
124 {
125 prop_dictionary_t cfg, dev;
126 prop_data_t dat;
127 char *xml;
128 int fd;
129 size_t len;
130
131 cfg = load_keys();
132 if (cfg == NULL) {
133 cfg = prop_dictionary_create();
134 if (cfg == NULL) {
135 syslog(LOG_ERR, "prop_dictionary_create() failed: %m");
136 return;
137 }
138 }
139
140 dev = prop_dictionary_get(cfg, bt_ntoa(laddr, NULL));
141 if (dev == NULL) {
142 dev = prop_dictionary_create();
143 if (dev == NULL) {
144 syslog(LOG_ERR, "prop_dictionary_create() failed: %m");
145 prop_object_release(cfg);
146 return;
147 }
148
149 if (!prop_dictionary_set(cfg, bt_ntoa(laddr, NULL), dev)) {
150 syslog(LOG_ERR, "prop_dictionary_set() failed: %m");
151 prop_object_release(dev);
152 prop_object_release(cfg);
153 return;
154 }
155
156 prop_object_release(dev);
157 }
158
159 dat = prop_data_create_nocopy(key, HCI_KEY_SIZE);
160 if (dat == NULL) {
161 syslog(LOG_ERR, "Cannot create data object: %m");
162 prop_object_release(cfg);
163 return;
164 }
165
166 if (!prop_dictionary_set(dev, bt_ntoa(raddr, NULL), dat)) {
167 syslog(LOG_ERR, "prop_dictionary_set() failed: %m");
168 prop_object_release(dat);
169 prop_object_release(cfg);
170 return;
171 }
172
173 prop_object_release(dat);
174
175 xml = prop_dictionary_externalize(cfg);
176 if (xml == NULL) {
177 syslog(LOG_ERR, "prop_dictionary_externalize() failed: %m");
178 prop_object_release(cfg);
179 return;
180 }
181
182 prop_object_release(cfg);
183
184 fd = open(new_key_file, O_WRONLY|O_TRUNC|O_CREAT|O_EXLOCK, 0600);
185 if (fd < 0) {
186 syslog(LOG_ERR, "Cannot open new keyfile %s: %m", key_file);
187 free(xml);
188 return;
189 }
190
191 len = strlen(xml);
192 if ((size_t)write(fd, xml, len) != len) {
193 syslog(LOG_ERR, "Write of keyfile failed: %m");
194 free(xml);
195 close(fd);
196 unlink(new_key_file);
197 return;
198 }
199
200 free(xml);
201 close(fd);
202
203 if (rename(new_key_file, key_file) < 0) {
204 syslog(LOG_ERR, "rename(%s, %s) failed: %m",
205 new_key_file, key_file);
206
207 unlink(new_key_file);
208 }
209 }
210