xref: /freebsd/usr.sbin/bluetooth/hcsecd/parser.y (revision d3d381b2b194b4d24853e92eecef55f262688d1a)
1 %{
2 /*-
3  * parser.y
4  *
5  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
6  *
7  * Copyright (c) 2001-2002 Maksim Yevmenkin <m_evmenkin@yahoo.com>
8  * All rights reserved.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  * $Id: parser.y,v 1.5 2003/06/07 21:22:30 max Exp $
32  * $FreeBSD$
33  */
34 
35 #include <sys/fcntl.h>
36 #include <sys/queue.h>
37 #define L2CAP_SOCKET_CHECKED
38 #include <bluetooth.h>
39 #include <errno.h>
40 #include <limits.h>
41 #include <stdio.h>
42 #include <stdlib.h>
43 #include <stdarg.h>
44 #include <string.h>
45 #include <syslog.h>
46 #include <unistd.h>
47 #include "hcsecd.h"
48 
49 	int	yyparse  (void);
50 	int	yylex    (void);
51 
52 static	void	free_key (link_key_p key);
53 static	int	hexa2int4(char *a);
54 static	int	hexa2int8(char *a);
55 
56 extern	int			 yylineno;
57 static	LIST_HEAD(, link_key)	 link_keys;
58 	char			*config_file = "/etc/bluetooth/hcsecd.conf";
59 
60 static	link_key_p		 key = NULL;
61 %}
62 
63 %union {
64 	char	*string;
65 }
66 
67 %token <string> T_BDADDRSTRING T_HEXSTRING T_STRING
68 %token T_DEVICE T_BDADDR T_NAME T_KEY T_PIN T_NOKEY T_NOPIN T_JUNK
69 
70 %%
71 
72 config:		line
73 		| config line
74 		;
75 
76 line:		T_DEVICE
77 			{
78 			key = (link_key_p) malloc(sizeof(*key));
79 			if (key == NULL) {
80 				syslog(LOG_ERR, "Could not allocate new " \
81 						"config entry");
82 				exit(1);
83 			}
84 
85 			memset(key, 0, sizeof(*key));
86 			}
87 		'{' options '}'
88 			{
89 			if (get_key(&key->bdaddr, 1) != NULL) {
90 				syslog(LOG_ERR, "Ignoring duplicated entry " \
91 						"for bdaddr %s",
92 						bt_ntoa(&key->bdaddr, NULL));
93 				free_key(key);
94 			} else
95 				LIST_INSERT_HEAD(&link_keys, key, next);
96 
97 			key = NULL;
98 			}
99 		;
100 
101 options:	option ';'
102 		| options option ';'
103 		;
104 
105 option:		bdaddr
106 		| name
107 		| key
108 		| pin
109 		;
110 
111 bdaddr:		T_BDADDR T_BDADDRSTRING
112 			{
113 			if (!bt_aton($2, &key->bdaddr)) {
114 				syslog(LOG_ERR, "Cound not parse BD_ADDR " \
115 						"'%s'", $2);
116 				exit(1);
117 			}
118 			}
119 		;
120 
121 name:		T_NAME T_STRING
122 			{
123 			if (key->name != NULL)
124 				free(key->name);
125 
126 			key->name = strdup($2);
127 			if (key->name == NULL) {
128 				syslog(LOG_ERR, "Could not allocate new " \
129 						"device name");
130 				exit(1);
131 			}
132 			}
133 		;
134 
135 key:		T_KEY T_HEXSTRING
136 			{
137 			int	i, len;
138 
139 			if (key->key != NULL)
140 				free(key->key);
141 
142 			key->key = (uint8_t *) malloc(NG_HCI_KEY_SIZE);
143 			if (key->key == NULL) {
144 				syslog(LOG_ERR, "Could not allocate new " \
145 						"link key");
146 				exit(1);
147 			}
148 
149 			memset(key->key, 0, NG_HCI_KEY_SIZE);
150 
151 			len = strlen($2) / 2;
152 			if (len > NG_HCI_KEY_SIZE)
153 				len = NG_HCI_KEY_SIZE;
154 
155 			for (i = 0; i < len; i ++)
156 				key->key[i] = hexa2int8((char *)($2) + 2*i);
157 			}
158 		| T_KEY T_NOKEY
159 			{
160 			if (key->key != NULL)
161 				free(key->key);
162 
163 			key->key = NULL;
164 			}
165 		;
166 
167 pin:		T_PIN T_STRING
168 			{
169 			if (key->pin != NULL)
170 				free(key->pin);
171 
172 			key->pin = strdup($2);
173 			if (key->pin == NULL) {
174 				syslog(LOG_ERR, "Could not allocate new " \
175 						"PIN code");
176 				exit(1);
177 			}
178 			}
179 		| T_PIN T_NOPIN
180 			{
181 			if (key->pin != NULL)
182 				free(key->pin);
183 
184 			key->pin = NULL;
185 			}
186 		;
187 
188 %%
189 
190 /* Display parser error message */
191 void
192 yyerror(char const *message)
193 {
194 	syslog(LOG_ERR, "%s in line %d", message, yylineno);
195 }
196 
197 /* Re-read config file */
198 void
199 read_config_file(void)
200 {
201 	extern FILE	*yyin;
202 
203 	if (config_file == NULL) {
204 		syslog(LOG_ERR, "Unknown config file name!");
205 		exit(1);
206 	}
207 
208 	if ((yyin = fopen(config_file, "r")) == NULL) {
209 		syslog(LOG_ERR, "Could not open config file '%s'. %s (%d)",
210 				config_file, strerror(errno), errno);
211 		exit(1);
212 	}
213 
214 	clean_config();
215 	if (yyparse() < 0) {
216 		syslog(LOG_ERR, "Could not parse config file '%s'",config_file);
217 		exit(1);
218 	}
219 
220 	fclose(yyin);
221 	yyin = NULL;
222 
223 #if __config_debug__
224 	dump_config();
225 #endif
226 }
227 
228 /* Clean config */
229 void
230 clean_config(void)
231 {
232 	link_key_p	key = NULL;
233 
234 	while ((key = LIST_FIRST(&link_keys)) != NULL) {
235 		LIST_REMOVE(key, next);
236 		free_key(key);
237 	}
238 }
239 
240 /* Find link key entry in the list. Return exact or default match */
241 link_key_p
242 get_key(bdaddr_p bdaddr, int exact_match)
243 {
244 	link_key_p	key = NULL, defkey = NULL;
245 
246 	LIST_FOREACH(key, &link_keys, next) {
247 		if (memcmp(bdaddr, &key->bdaddr, sizeof(key->bdaddr)) == 0)
248 			break;
249 
250 		if (!exact_match)
251 			if (memcmp(NG_HCI_BDADDR_ANY, &key->bdaddr,
252 					sizeof(key->bdaddr)) == 0)
253 				defkey = key;
254 	}
255 
256 	return ((key != NULL)? key : defkey);
257 }
258 
259 #if __config_debug__
260 /* Dump config */
261 void
262 dump_config(void)
263 {
264 	link_key_p	key = NULL;
265 	char		buffer[64];
266 
267 	LIST_FOREACH(key, &link_keys, next) {
268 		if (key->key != NULL)
269 			snprintf(buffer, sizeof(buffer),
270 "0x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x",
271 				key->key[0], key->key[1], key->key[2],
272 				key->key[3], key->key[4], key->key[5],
273 				key->key[6], key->key[7], key->key[8],
274 				key->key[9], key->key[10], key->key[11],
275 				key->key[12], key->key[13], key->key[14],
276 				key->key[15]);
277 
278 		syslog(LOG_DEBUG,
279 "device %s " \
280 "bdaddr %s " \
281 "pin %s " \
282 "key %s",
283 			(key->name != NULL)? key->name : "noname",
284 			bt_ntoa(&key->bdaddr, NULL),
285 			(key->pin != NULL)? key->pin : "nopin",
286 			(key->key != NULL)? buffer : "nokey");
287 	}
288 }
289 #endif
290 
291 /* Read keys file */
292 int
293 read_keys_file(void)
294 {
295 	FILE		*f = NULL;
296 	link_key_t	*key = NULL;
297 	char		 buf[HCSECD_BUFFER_SIZE], *p = NULL, *cp = NULL;
298 	bdaddr_t	 bdaddr;
299 	int		 i, len;
300 
301 	if ((f = fopen(HCSECD_KEYSFILE, "r")) == NULL) {
302 		if (errno == ENOENT)
303 			return (0);
304 
305 		syslog(LOG_ERR, "Could not open keys file %s. %s (%d)\n",
306 				HCSECD_KEYSFILE, strerror(errno), errno);
307 
308 		return (-1);
309 	}
310 
311 	while ((p = fgets(buf, sizeof(buf), f)) != NULL) {
312 		if (*p == '#')
313 			continue;
314 		if ((cp = strpbrk(p, " ")) == NULL)
315 			continue;
316 
317 		*cp++ = '\0';
318 
319 		if (!bt_aton(p, &bdaddr))
320 			continue;
321 
322 		if ((key = get_key(&bdaddr, 1)) == NULL)
323 			continue;
324 
325 		if (key->key == NULL) {
326 			key->key = (uint8_t *) malloc(NG_HCI_KEY_SIZE);
327 			if (key->key == NULL) {
328 				syslog(LOG_ERR, "Could not allocate link key");
329 				exit(1);
330 			}
331 		}
332 
333 		memset(key->key, 0, NG_HCI_KEY_SIZE);
334 
335 		len = strlen(cp) / 2;
336 		if (len > NG_HCI_KEY_SIZE)
337 			len = NG_HCI_KEY_SIZE;
338 
339 		for (i = 0; i < len; i ++)
340 			key->key[i] = hexa2int8(cp + 2*i);
341 
342 		syslog(LOG_DEBUG, "Restored link key for the entry, " \
343 				"remote bdaddr %s, name '%s'",
344 				bt_ntoa(&key->bdaddr, NULL),
345 				(key->name != NULL)? key->name : "No name");
346 	}
347 
348 	fclose(f);
349 
350 	return (0);
351 }
352 
353 /* Dump keys file */
354 int
355 dump_keys_file(void)
356 {
357 	link_key_p	key = NULL;
358 	char		tmp[PATH_MAX], buf[HCSECD_BUFFER_SIZE];
359 	int		f;
360 
361 	snprintf(tmp, sizeof(tmp), "%s.tmp", HCSECD_KEYSFILE);
362 	if ((f = open(tmp, O_RDWR|O_CREAT|O_TRUNC|O_EXCL, 0600)) < 0) {
363 		syslog(LOG_ERR, "Could not create temp keys file %s. %s (%d)\n",
364 				tmp, strerror(errno), errno);
365 		return (-1);
366 	}
367 
368 	LIST_FOREACH(key, &link_keys, next) {
369 		if (key->key == NULL)
370 			continue;
371 
372 		snprintf(buf, sizeof(buf),
373 "%s %02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x%02x\n",
374 			bt_ntoa(&key->bdaddr, NULL),
375 			key->key[0],  key->key[1],  key->key[2],  key->key[3],
376 			key->key[4],  key->key[5],  key->key[6],  key->key[7],
377 			key->key[8],  key->key[9],  key->key[10], key->key[11],
378 			key->key[12], key->key[13], key->key[14], key->key[15]);
379 
380 		if (write(f, buf, strlen(buf)) < 0) {
381 			syslog(LOG_ERR, "Could not write temp keys file. " \
382 					"%s (%d)\n", strerror(errno), errno);
383 			break;
384 		}
385 	}
386 
387 	close(f);
388 
389 	if (rename(tmp, HCSECD_KEYSFILE) < 0) {
390 		syslog(LOG_ERR, "Could not rename(%s, %s). %s (%d)\n",
391 				tmp, HCSECD_KEYSFILE, strerror(errno), errno);
392 		unlink(tmp);
393 		return (-1);
394 	}
395 
396 	return (0);
397 }
398 
399 /* Free key entry */
400 static void
401 free_key(link_key_p key)
402 {
403 	if (key->name != NULL)
404 		free(key->name);
405 	if (key->key != NULL)
406 		free(key->key);
407 	if (key->pin != NULL)
408 		free(key->pin);
409 
410 	memset(key, 0, sizeof(*key));
411 	free(key);
412 }
413 
414 /* Convert hex ASCII to int4 */
415 static int
416 hexa2int4(char *a)
417 {
418 	if ('0' <= *a && *a <= '9')
419 		return (*a - '0');
420 
421 	if ('A' <= *a && *a <= 'F')
422 		return (*a - 'A' + 0xa);
423 
424 	if ('a' <= *a && *a <= 'f')
425 		return (*a - 'a' + 0xa);
426 
427 	syslog(LOG_ERR, "Invalid hex character: '%c' (%#x)", *a, *a);
428 	exit(1);
429 }
430 
431 /* Convert hex ASCII to int8 */
432 static int
433 hexa2int8(char *a)
434 {
435 	return ((hexa2int4(a) << 4) | hexa2int4(a + 1));
436 }
437 
438