xref: /netbsd-src/usr.sbin/btpand/btpand.c (revision db203c8401d4119c621968413a441a456c83bf80)
1 /*	$NetBSD: btpand.c,v 1.9 2024/06/04 06:24:58 plunky Exp $	*/
2 
3 /*-
4  * Copyright (c) 2008-2009 Iain Hibbert
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  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __COPYRIGHT("@(#) Copyright (c) 2008-2009 Iain Hibbert. All rights reserved.");
30 __RCSID("$NetBSD: btpand.c,v 1.9 2024/06/04 06:24:58 plunky Exp $");
31 
32 #include <sys/wait.h>
33 
34 #include <bluetooth.h>
35 #include <err.h>
36 #include <fcntl.h>
37 #include <paths.h>
38 #include <sdp.h>
39 #include <stdio.h>
40 #include <signal.h>
41 #include <stdlib.h>
42 #include <string.h>
43 #include <unistd.h>
44 
45 #include "btpand.h"
46 
47 /* global variables */
48 const char *	control_path;		/* -c <path> */
49 const char *	interface_name;		/* -i <ifname> */
50 const char *	service_type;		/* -s <service> */
51 uint16_t	service_class;
52 const char *	service_name;
53 const char *	service_desc;
54 
55 bdaddr_t	local_bdaddr;		/* -d <addr> */
56 bdaddr_t	remote_bdaddr;		/* -a <addr> */
57 uint16_t	l2cap_psm;		/* -p <psm> */
58 int		l2cap_mode;		/* -m <mode> */
59 int		server_limit;		/* -n <limit> */
60 
61 static const struct {
62 	const char *	type;
63 	uint16_t	class;
64 	const char *	name;
65 	const char *	desc;
66 } services[] = {
67 	{ "PANU", SDP_SERVICE_CLASS_PANU,
68 	  "Personal Ad-hoc User Service",
69 	  "Personal Ad-hoc User Service"
70 	},
71 	{ "NAP",  SDP_SERVICE_CLASS_NAP,
72 	  "Network Access Point",
73 	  "Personal Ad-hoc Network Service"
74 	},
75 	{ "GN",	  SDP_SERVICE_CLASS_GN,
76 	  "Group Ad-hoc Network",
77 	  "Personal Group Ad-hoc Network Service"
78 	},
79 };
80 
81 __dead static void main_exit(int);
82 static void main_detach(void);
83 __dead static void usage(void);
84 
85 int
main(int argc,char * argv[])86 main(int argc, char *argv[])
87 {
88 	unsigned long	ul;
89 	char *		ep;
90 	int		ch, status;
91 
92 	while ((ch = getopt(argc, argv, "a:c:d:i:l:m:p:S:s:")) != -1) {
93 		switch (ch) {
94 		case 'a': /* remote address */
95 			if (!bt_aton(optarg, &remote_bdaddr)) {
96 				struct hostent  *he;
97 
98 				if ((he = bt_gethostbyname(optarg)) == NULL)
99 					errx(EXIT_FAILURE, "%s: %s",
100 					    optarg, hstrerror(h_errno));
101 
102 				bdaddr_copy(&remote_bdaddr, (bdaddr_t *)he->h_addr);
103 			}
104 
105 			break;
106 
107 		case 'c': /* control socket path */
108 			control_path = optarg;
109 			break;
110 
111 		case 'd': /* local address */
112 			if (!bt_devaddr(optarg, &local_bdaddr))
113 				err(EXIT_FAILURE, "%s", optarg);
114 
115 			break;
116 
117 		case 'i': /* tap interface name */
118 			if (strchr(optarg, '/') == NULL) {
119 				asprintf(&ep, "/dev/%s", optarg);
120 				interface_name = ep;
121 			} else {
122 				interface_name = optarg;
123 			}
124 
125 			break;
126 
127 		case 'l': /* limit server sessions */
128 			ul = strtoul(optarg, &ep, 10);
129 			if (*optarg == '\0' || *ep != '\0' || ul == 0)
130 				errx(EXIT_FAILURE, "%s: invalid session limit", optarg);
131 
132 			server_limit = ul;
133 			break;
134 
135 		case 'm': /* link mode */
136 			if (strcasecmp(optarg, "auth") == 0)
137 				l2cap_mode = L2CAP_LM_AUTH;
138 			else if (strcasecmp(optarg, "encrypt") == 0)
139 				l2cap_mode = L2CAP_LM_ENCRYPT;
140 			else if (strcasecmp(optarg, "secure") == 0)
141 				l2cap_mode = L2CAP_LM_SECURE;
142 			else if (strcasecmp(optarg, "none"))
143 				errx(EXIT_FAILURE, "%s: unknown mode", optarg);
144 
145 			break;
146 
147 		case 'p': /* protocol/service multiplexer */
148 			ul = strtoul(optarg, &ep, 0);
149 			if (*optarg == '\0' || *ep != '\0'
150 			    || ul > 0xffff || L2CAP_PSM_INVALID(ul))
151 				errx(EXIT_FAILURE, "%s: invalid PSM", optarg);
152 
153 			l2cap_psm = (uint16_t)ul;
154 			break;
155 
156 		case 's': /* service */
157 		case 'S': /* service (no SDP) */
158 			for (ul = 0; ul < __arraycount(services); ul++) {
159 				if (strcasecmp(optarg, services[ul].type) == 0)
160 					break;
161 			}
162 
163 			if (ul == __arraycount(services))
164 				errx(EXIT_FAILURE, "%s: unknown service", optarg);
165 
166 			if (ch == 's') {
167 				service_type = services[ul].type;
168 				service_name = services[ul].name;
169 				service_desc = services[ul].desc;
170 			}
171 
172 			service_class = services[ul].class;
173 			break;
174 
175 		default:
176 			usage();
177 			/* NOTREACHED */
178 		}
179 	}
180 
181 	argc -= optind;
182 	argv += optind;
183 
184 	/* validate options */
185 	if (bdaddr_any(&local_bdaddr) || service_class == 0)
186 		usage();
187 
188 	if (!bdaddr_any(&remote_bdaddr) && (server_limit != 0 ||
189 	    control_path != 0 || (service_type != NULL && l2cap_psm != 0)))
190 		usage();
191 
192 	/* default options */
193 	if (interface_name == NULL)
194 		interface_name = "/dev/tap";
195 
196 	if (l2cap_psm == 0)
197 		l2cap_psm = L2CAP_PSM_BNEP;
198 
199 	if (bdaddr_any(&remote_bdaddr) && server_limit == 0) {
200 		if (service_class == SDP_SERVICE_CLASS_PANU)
201 			server_limit = 1;
202 		else
203 			server_limit = 7;
204 	}
205 
206 #ifdef L2CAP_LM_MASTER
207 	if (server_limit > 1 && service_class != SDP_SERVICE_CLASS_PANU)
208 		l2cap_mode |= L2CAP_LM_MASTER;
209 #endif
210 
211 	/*
212 	 * fork() now so that the setup can be done in the child process
213 	 * (as kqueue is not inherited) but block in the parent until the
214 	 * setup is finished so we can return an error if necessary.
215 	 */
216 	switch(fork()) {
217 	case -1: /* bad */
218 		err(EXIT_FAILURE, "fork() failed");
219 		/*NOTREACHED*/
220 
221 	case 0:	/* child */
222 		openlog(getprogname(), LOG_NDELAY | LOG_PERROR | LOG_PID, LOG_DAEMON);
223 
224 		channel_init();
225 		event_init();
226 		server_init();
227 		client_init();
228 		tap_init();
229 
230 		main_detach();
231 
232 		event_dispatch();
233 		break;
234 
235 	default: /* parent */
236 		signal(SIGUSR1, main_exit);
237 		wait(&status);
238 
239 		if (WIFEXITED(status))
240 			exit(WEXITSTATUS(status));
241 
242 		break;
243 	}
244 
245 	err(EXIT_FAILURE, "exiting");
246 }
247 
248 static void
main_exit(int s)249 main_exit(int s)
250 {
251 
252 	/* child is all grown up */
253 	_exit(EXIT_SUCCESS);
254 }
255 
256 static void
main_detach(void)257 main_detach(void)
258 {
259 	int fd;
260 
261 	if (kill(getppid(), SIGUSR1) == -1)
262 		log_err("Could not signal main process: %m");
263 
264 	if (setsid() == -1)
265 		log_err("setsid() failed");
266 
267 	fd = open(_PATH_DEVNULL, O_RDWR, 0);
268 	if (fd == -1) {
269 		log_err("Could not open %s", _PATH_DEVNULL);
270 	} else {
271 		(void)dup2(fd, STDIN_FILENO);
272 		(void)dup2(fd, STDOUT_FILENO);
273 		(void)dup2(fd, STDERR_FILENO);
274 		close(fd);
275 	}
276 }
277 
278 static void
usage(void)279 usage(void)
280 {
281 	const char *p = getprogname();
282 	size_t n = strlen(p);
283 
284 	fprintf(stderr,
285 	    "usage: %s [-i ifname] [-m mode] -a address -d device\n"
286 	    "       %*s {-s service | -S service [-p psm]}\n"
287 	    "       %s [-c path] [-i ifname] [-l limit] [-m mode] [-p psm] -d device\n"
288 	    "       %*s {-s service | -S service}\n"
289 	    "\n"
290 	    "Where:\n"
291 	    "\t-a address  remote bluetooth device\n"
292 	    "\t-c path     SDP server socket\n"
293 	    "\t-d device   local bluetooth device\n"
294 	    "\t-i ifname   tap interface\n"
295 	    "\t-l limit    limit server sessions\n"
296 	    "\t-m mode     L2CAP link mode\n"
297 	    "\t-p psm      L2CAP PSM\n"
298 	    "\t-S service  service name (no SDP)\n"
299 	    "\t-s service  service name\n"
300 	    "\n"
301 	    "Known services:\n"
302 	    "", p, (int)n, "", p, (int)n, "");
303 
304 	for (n = 0; n < __arraycount(services); n++)
305 		fprintf(stderr, "\t%s\t%s\n", services[n].type, services[n].name);
306 
307 	exit(EXIT_FAILURE);
308 }
309