xref: /linux/tools/usb/usbip/src/usbipd.c (revision 24bce201d79807b668bf9d9e0aca801c5c0d5f78)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2011 matt mooney <mfm@muteddisk.com>
4  *               2005-2007 Takahiro Hirofuchi
5  * Copyright (C) 2015-2016 Samsung Electronics
6  *               Igor Kotrasinski <i.kotrasinsk@samsung.com>
7  *               Krzysztof Opasiak <k.opasiak@samsung.com>
8  */
9 
10 #ifdef HAVE_CONFIG_H
11 #include "../config.h"
12 #endif
13 
14 #define _GNU_SOURCE
15 #include <errno.h>
16 #include <unistd.h>
17 #include <netdb.h>
18 #include <string.h>
19 #include <stdlib.h>
20 #include <sys/types.h>
21 #include <sys/stat.h>
22 #include <arpa/inet.h>
23 #include <sys/socket.h>
24 #include <netinet/in.h>
25 
26 #ifdef HAVE_LIBWRAP
27 #include <tcpd.h>
28 #endif
29 
30 #include <getopt.h>
31 #include <signal.h>
32 #include <poll.h>
33 
34 #include "usbip_host_driver.h"
35 #include "usbip_host_common.h"
36 #include "usbip_device_driver.h"
37 #include "usbip_common.h"
38 #include "usbip_network.h"
39 #include "list.h"
40 
41 #undef  PROGNAME
42 #define PROGNAME "usbipd"
43 #define MAXSOCKFD 20
44 
45 #define MAIN_LOOP_TIMEOUT 10
46 
47 #define DEFAULT_PID_FILE "/var/run/" PROGNAME ".pid"
48 
49 static const char usbip_version_string[] = PACKAGE_STRING;
50 
51 static const char usbipd_help_string[] =
52 	"usage: usbipd [options]\n"
53 	"\n"
54 	"	-4, --ipv4\n"
55 	"		Bind to IPv4. Default is both.\n"
56 	"\n"
57 	"	-6, --ipv6\n"
58 	"		Bind to IPv6. Default is both.\n"
59 	"\n"
60 	"	-e, --device\n"
61 	"		Run in device mode.\n"
62 	"		Rather than drive an attached device, create\n"
63 	"		a virtual UDC to bind gadgets to.\n"
64 	"\n"
65 	"	-D, --daemon\n"
66 	"		Run as a daemon process.\n"
67 	"\n"
68 	"	-d, --debug\n"
69 	"		Print debugging information.\n"
70 	"\n"
71 	"	-PFILE, --pid FILE\n"
72 	"		Write process id to FILE.\n"
73 	"		If no FILE specified, use " DEFAULT_PID_FILE "\n"
74 	"\n"
75 	"	-tPORT, --tcp-port PORT\n"
76 	"		Listen on TCP/IP port PORT.\n"
77 	"\n"
78 	"	-h, --help\n"
79 	"		Print this help.\n"
80 	"\n"
81 	"	-v, --version\n"
82 	"		Show version.\n";
83 
84 static struct usbip_host_driver *driver;
85 
86 static void usbipd_help(void)
87 {
88 	printf("%s\n", usbipd_help_string);
89 }
90 
91 static int recv_request_import(int sockfd)
92 {
93 	struct op_import_request req;
94 	struct usbip_exported_device *edev;
95 	struct usbip_usb_device pdu_udev;
96 	struct list_head *i;
97 	int found = 0;
98 	int status = ST_OK;
99 	int rc;
100 
101 	memset(&req, 0, sizeof(req));
102 
103 	rc = usbip_net_recv(sockfd, &req, sizeof(req));
104 	if (rc < 0) {
105 		dbg("usbip_net_recv failed: import request");
106 		return -1;
107 	}
108 	PACK_OP_IMPORT_REQUEST(0, &req);
109 
110 	list_for_each(i, &driver->edev_list) {
111 		edev = list_entry(i, struct usbip_exported_device, node);
112 		if (!strncmp(req.busid, edev->udev.busid, SYSFS_BUS_ID_SIZE)) {
113 			info("found requested device: %s", req.busid);
114 			found = 1;
115 			break;
116 		}
117 	}
118 
119 	if (found) {
120 		/* should set TCP_NODELAY for usbip */
121 		usbip_net_set_nodelay(sockfd);
122 
123 		/* export device needs a TCP/IP socket descriptor */
124 		status = usbip_export_device(edev, sockfd);
125 		if (status < 0)
126 			status = ST_NA;
127 	} else {
128 		info("requested device not found: %s", req.busid);
129 		status = ST_NODEV;
130 	}
131 
132 	rc = usbip_net_send_op_common(sockfd, OP_REP_IMPORT, status);
133 	if (rc < 0) {
134 		dbg("usbip_net_send_op_common failed: %#0x", OP_REP_IMPORT);
135 		return -1;
136 	}
137 
138 	if (status) {
139 		dbg("import request busid %s: failed", req.busid);
140 		return -1;
141 	}
142 
143 	memcpy(&pdu_udev, &edev->udev, sizeof(pdu_udev));
144 	usbip_net_pack_usb_device(1, &pdu_udev);
145 
146 	rc = usbip_net_send(sockfd, &pdu_udev, sizeof(pdu_udev));
147 	if (rc < 0) {
148 		dbg("usbip_net_send failed: devinfo");
149 		return -1;
150 	}
151 
152 	dbg("import request busid %s: complete", req.busid);
153 
154 	return 0;
155 }
156 
157 static int send_reply_devlist(int connfd)
158 {
159 	struct usbip_exported_device *edev;
160 	struct usbip_usb_device pdu_udev;
161 	struct usbip_usb_interface pdu_uinf;
162 	struct op_devlist_reply reply;
163 	struct list_head *j;
164 	int rc, i;
165 
166 	/*
167 	 * Exclude devices that are already exported to a client from
168 	 * the exportable device list to avoid:
169 	 *	- import requests for devices that are exported only to
170 	 *	  fail the request.
171 	 *	- revealing devices that are imported by a client to
172 	 *	  another client.
173 	 */
174 
175 	reply.ndev = 0;
176 	/* number of exported devices */
177 	list_for_each(j, &driver->edev_list) {
178 		edev = list_entry(j, struct usbip_exported_device, node);
179 		if (edev->status != SDEV_ST_USED)
180 			reply.ndev += 1;
181 	}
182 	info("exportable devices: %d", reply.ndev);
183 
184 	rc = usbip_net_send_op_common(connfd, OP_REP_DEVLIST, ST_OK);
185 	if (rc < 0) {
186 		dbg("usbip_net_send_op_common failed: %#0x", OP_REP_DEVLIST);
187 		return -1;
188 	}
189 	PACK_OP_DEVLIST_REPLY(1, &reply);
190 
191 	rc = usbip_net_send(connfd, &reply, sizeof(reply));
192 	if (rc < 0) {
193 		dbg("usbip_net_send failed: %#0x", OP_REP_DEVLIST);
194 		return -1;
195 	}
196 
197 	list_for_each(j, &driver->edev_list) {
198 		edev = list_entry(j, struct usbip_exported_device, node);
199 		if (edev->status == SDEV_ST_USED)
200 			continue;
201 
202 		dump_usb_device(&edev->udev);
203 		memcpy(&pdu_udev, &edev->udev, sizeof(pdu_udev));
204 		usbip_net_pack_usb_device(1, &pdu_udev);
205 
206 		rc = usbip_net_send(connfd, &pdu_udev, sizeof(pdu_udev));
207 		if (rc < 0) {
208 			dbg("usbip_net_send failed: pdu_udev");
209 			return -1;
210 		}
211 
212 		for (i = 0; i < edev->udev.bNumInterfaces; i++) {
213 			dump_usb_interface(&edev->uinf[i]);
214 			memcpy(&pdu_uinf, &edev->uinf[i], sizeof(pdu_uinf));
215 			usbip_net_pack_usb_interface(1, &pdu_uinf);
216 
217 			rc = usbip_net_send(connfd, &pdu_uinf,
218 					sizeof(pdu_uinf));
219 			if (rc < 0) {
220 				err("usbip_net_send failed: pdu_uinf");
221 				return -1;
222 			}
223 		}
224 	}
225 
226 	return 0;
227 }
228 
229 static int recv_request_devlist(int connfd)
230 {
231 	struct op_devlist_request req;
232 	int rc;
233 
234 	memset(&req, 0, sizeof(req));
235 
236 	rc = usbip_net_recv(connfd, &req, sizeof(req));
237 	if (rc < 0) {
238 		dbg("usbip_net_recv failed: devlist request");
239 		return -1;
240 	}
241 
242 	rc = send_reply_devlist(connfd);
243 	if (rc < 0) {
244 		dbg("send_reply_devlist failed");
245 		return -1;
246 	}
247 
248 	return 0;
249 }
250 
251 static int recv_pdu(int connfd)
252 {
253 	uint16_t code = OP_UNSPEC;
254 	int ret;
255 	int status;
256 
257 	ret = usbip_net_recv_op_common(connfd, &code, &status);
258 	if (ret < 0) {
259 		dbg("could not receive opcode: %#0x", code);
260 		return -1;
261 	}
262 
263 	ret = usbip_refresh_device_list(driver);
264 	if (ret < 0) {
265 		dbg("could not refresh device list: %d", ret);
266 		return -1;
267 	}
268 
269 	info("received request: %#0x(%d)", code, connfd);
270 	switch (code) {
271 	case OP_REQ_DEVLIST:
272 		ret = recv_request_devlist(connfd);
273 		break;
274 	case OP_REQ_IMPORT:
275 		ret = recv_request_import(connfd);
276 		break;
277 	case OP_REQ_DEVINFO:
278 	case OP_REQ_CRYPKEY:
279 	default:
280 		err("received an unknown opcode: %#0x", code);
281 		ret = -1;
282 	}
283 
284 	if (ret == 0)
285 		info("request %#0x(%d): complete", code, connfd);
286 	else
287 		info("request %#0x(%d): failed", code, connfd);
288 
289 	return ret;
290 }
291 
292 #ifdef HAVE_LIBWRAP
293 static int tcpd_auth(int connfd)
294 {
295 	struct request_info request;
296 	int rc;
297 
298 	request_init(&request, RQ_DAEMON, PROGNAME, RQ_FILE, connfd, 0);
299 	fromhost(&request);
300 	rc = hosts_access(&request);
301 	if (rc == 0)
302 		return -1;
303 
304 	return 0;
305 }
306 #endif
307 
308 static int do_accept(int listenfd)
309 {
310 	int connfd;
311 	struct sockaddr_storage ss;
312 	socklen_t len = sizeof(ss);
313 	char host[NI_MAXHOST], port[NI_MAXSERV];
314 	int rc;
315 
316 	memset(&ss, 0, sizeof(ss));
317 
318 	connfd = accept(listenfd, (struct sockaddr *)&ss, &len);
319 	if (connfd < 0) {
320 		err("failed to accept connection");
321 		return -1;
322 	}
323 
324 	rc = getnameinfo((struct sockaddr *)&ss, len, host, sizeof(host),
325 			 port, sizeof(port), NI_NUMERICHOST | NI_NUMERICSERV);
326 	if (rc)
327 		err("getnameinfo: %s", gai_strerror(rc));
328 
329 #ifdef HAVE_LIBWRAP
330 	rc = tcpd_auth(connfd);
331 	if (rc < 0) {
332 		info("denied access from %s", host);
333 		close(connfd);
334 		return -1;
335 	}
336 #endif
337 	info("connection from %s:%s", host, port);
338 
339 	return connfd;
340 }
341 
342 int process_request(int listenfd)
343 {
344 	pid_t childpid;
345 	int connfd;
346 
347 	connfd = do_accept(listenfd);
348 	if (connfd < 0)
349 		return -1;
350 	childpid = fork();
351 	if (childpid == 0) {
352 		close(listenfd);
353 		recv_pdu(connfd);
354 		exit(0);
355 	}
356 	close(connfd);
357 	return 0;
358 }
359 
360 static void addrinfo_to_text(struct addrinfo *ai, char buf[],
361 			     const size_t buf_size)
362 {
363 	char hbuf[NI_MAXHOST];
364 	char sbuf[NI_MAXSERV];
365 	int rc;
366 
367 	buf[0] = '\0';
368 
369 	rc = getnameinfo(ai->ai_addr, ai->ai_addrlen, hbuf, sizeof(hbuf),
370 			 sbuf, sizeof(sbuf), NI_NUMERICHOST | NI_NUMERICSERV);
371 	if (rc)
372 		err("getnameinfo: %s", gai_strerror(rc));
373 
374 	snprintf(buf, buf_size, "%s:%s", hbuf, sbuf);
375 }
376 
377 static int listen_all_addrinfo(struct addrinfo *ai_head, int sockfdlist[],
378 			     int maxsockfd)
379 {
380 	struct addrinfo *ai;
381 	int ret, nsockfd = 0;
382 	const size_t ai_buf_size = NI_MAXHOST + NI_MAXSERV + 2;
383 	char ai_buf[ai_buf_size];
384 
385 	for (ai = ai_head; ai && nsockfd < maxsockfd; ai = ai->ai_next) {
386 		int sock;
387 
388 		addrinfo_to_text(ai, ai_buf, ai_buf_size);
389 		dbg("opening %s", ai_buf);
390 		sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
391 		if (sock < 0) {
392 			err("socket: %s: %d (%s)",
393 			    ai_buf, errno, strerror(errno));
394 			continue;
395 		}
396 
397 		usbip_net_set_reuseaddr(sock);
398 		usbip_net_set_nodelay(sock);
399 		/* We use seperate sockets for IPv4 and IPv6
400 		 * (see do_standalone_mode()) */
401 		usbip_net_set_v6only(sock);
402 
403 		ret = bind(sock, ai->ai_addr, ai->ai_addrlen);
404 		if (ret < 0) {
405 			err("bind: %s: %d (%s)",
406 			    ai_buf, errno, strerror(errno));
407 			close(sock);
408 			continue;
409 		}
410 
411 		ret = listen(sock, SOMAXCONN);
412 		if (ret < 0) {
413 			err("listen: %s: %d (%s)",
414 			    ai_buf, errno, strerror(errno));
415 			close(sock);
416 			continue;
417 		}
418 
419 		info("listening on %s", ai_buf);
420 		sockfdlist[nsockfd++] = sock;
421 	}
422 
423 	return nsockfd;
424 }
425 
426 static struct addrinfo *do_getaddrinfo(char *host, int ai_family)
427 {
428 	struct addrinfo hints, *ai_head;
429 	int rc;
430 
431 	memset(&hints, 0, sizeof(hints));
432 	hints.ai_family   = ai_family;
433 	hints.ai_socktype = SOCK_STREAM;
434 	hints.ai_flags    = AI_PASSIVE;
435 
436 	rc = getaddrinfo(host, usbip_port_string, &hints, &ai_head);
437 	if (rc) {
438 		err("failed to get a network address %s: %s", usbip_port_string,
439 		    gai_strerror(rc));
440 		return NULL;
441 	}
442 
443 	return ai_head;
444 }
445 
446 static void signal_handler(int i)
447 {
448 	dbg("received '%s' signal", strsignal(i));
449 }
450 
451 static void set_signal(void)
452 {
453 	struct sigaction act;
454 
455 	memset(&act, 0, sizeof(act));
456 	act.sa_handler = signal_handler;
457 	sigemptyset(&act.sa_mask);
458 	sigaction(SIGTERM, &act, NULL);
459 	sigaction(SIGINT, &act, NULL);
460 	act.sa_handler = SIG_IGN;
461 	sigaction(SIGCHLD, &act, NULL);
462 }
463 
464 static const char *pid_file;
465 
466 static void write_pid_file(void)
467 {
468 	if (pid_file) {
469 		dbg("creating pid file %s", pid_file);
470 		FILE *fp;
471 
472 		fp = fopen(pid_file, "w");
473 		if (!fp) {
474 			err("pid_file: %s: %d (%s)",
475 			    pid_file, errno, strerror(errno));
476 			return;
477 		}
478 		fprintf(fp, "%d\n", getpid());
479 		fclose(fp);
480 	}
481 }
482 
483 static void remove_pid_file(void)
484 {
485 	if (pid_file) {
486 		dbg("removing pid file %s", pid_file);
487 		unlink(pid_file);
488 	}
489 }
490 
491 static int do_standalone_mode(int daemonize, int ipv4, int ipv6)
492 {
493 	struct addrinfo *ai_head;
494 	int sockfdlist[MAXSOCKFD];
495 	int nsockfd, family;
496 	int i, terminate;
497 	struct pollfd *fds;
498 	struct timespec timeout;
499 	sigset_t sigmask;
500 
501 	if (usbip_driver_open(driver))
502 		return -1;
503 
504 	if (daemonize) {
505 		if (daemon(0, 0) < 0) {
506 			err("daemonizing failed: %s", strerror(errno));
507 			usbip_driver_close(driver);
508 			return -1;
509 		}
510 		umask(0);
511 		usbip_use_syslog = 1;
512 	}
513 	set_signal();
514 	write_pid_file();
515 
516 	info("starting " PROGNAME " (%s)", usbip_version_string);
517 
518 	/*
519 	 * To suppress warnings on systems with bindv6only disabled
520 	 * (default), we use seperate sockets for IPv6 and IPv4 and set
521 	 * IPV6_V6ONLY on the IPv6 sockets.
522 	 */
523 	if (ipv4 && ipv6)
524 		family = AF_UNSPEC;
525 	else if (ipv4)
526 		family = AF_INET;
527 	else
528 		family = AF_INET6;
529 
530 	ai_head = do_getaddrinfo(NULL, family);
531 	if (!ai_head) {
532 		usbip_driver_close(driver);
533 		return -1;
534 	}
535 	nsockfd = listen_all_addrinfo(ai_head, sockfdlist,
536 		sizeof(sockfdlist) / sizeof(*sockfdlist));
537 	freeaddrinfo(ai_head);
538 	if (nsockfd <= 0) {
539 		err("failed to open a listening socket");
540 		usbip_driver_close(driver);
541 		return -1;
542 	}
543 
544 	dbg("listening on %d address%s", nsockfd, (nsockfd == 1) ? "" : "es");
545 
546 	fds = calloc(nsockfd, sizeof(struct pollfd));
547 	for (i = 0; i < nsockfd; i++) {
548 		fds[i].fd = sockfdlist[i];
549 		fds[i].events = POLLIN;
550 	}
551 	timeout.tv_sec = MAIN_LOOP_TIMEOUT;
552 	timeout.tv_nsec = 0;
553 
554 	sigfillset(&sigmask);
555 	sigdelset(&sigmask, SIGTERM);
556 	sigdelset(&sigmask, SIGINT);
557 
558 	terminate = 0;
559 	while (!terminate) {
560 		int r;
561 
562 		r = ppoll(fds, nsockfd, &timeout, &sigmask);
563 		if (r < 0) {
564 			dbg("%s", strerror(errno));
565 			terminate = 1;
566 		} else if (r) {
567 			for (i = 0; i < nsockfd; i++) {
568 				if (fds[i].revents & POLLIN) {
569 					dbg("read event on fd[%d]=%d",
570 					    i, sockfdlist[i]);
571 					process_request(sockfdlist[i]);
572 				}
573 			}
574 		} else {
575 			dbg("heartbeat timeout on ppoll()");
576 		}
577 	}
578 
579 	info("shutting down " PROGNAME);
580 	free(fds);
581 	usbip_driver_close(driver);
582 
583 	return 0;
584 }
585 
586 int main(int argc, char *argv[])
587 {
588 	static const struct option longopts[] = {
589 		{ "ipv4",     no_argument,       NULL, '4' },
590 		{ "ipv6",     no_argument,       NULL, '6' },
591 		{ "daemon",   no_argument,       NULL, 'D' },
592 		{ "daemon",   no_argument,       NULL, 'D' },
593 		{ "debug",    no_argument,       NULL, 'd' },
594 		{ "device",   no_argument,       NULL, 'e' },
595 		{ "pid",      optional_argument, NULL, 'P' },
596 		{ "tcp-port", required_argument, NULL, 't' },
597 		{ "help",     no_argument,       NULL, 'h' },
598 		{ "version",  no_argument,       NULL, 'v' },
599 		{ NULL,	      0,                 NULL,  0  }
600 	};
601 
602 	enum {
603 		cmd_standalone_mode = 1,
604 		cmd_help,
605 		cmd_version
606 	} cmd;
607 
608 	int daemonize = 0;
609 	int ipv4 = 0, ipv6 = 0;
610 	int opt, rc = -1;
611 
612 	pid_file = NULL;
613 
614 	usbip_use_stderr = 1;
615 	usbip_use_syslog = 0;
616 
617 	if (geteuid() != 0)
618 		err("not running as root?");
619 
620 	cmd = cmd_standalone_mode;
621 	driver = &host_driver;
622 	for (;;) {
623 		opt = getopt_long(argc, argv, "46DdeP::t:hv", longopts, NULL);
624 
625 		if (opt == -1)
626 			break;
627 
628 		switch (opt) {
629 		case '4':
630 			ipv4 = 1;
631 			break;
632 		case '6':
633 			ipv6 = 1;
634 			break;
635 		case 'D':
636 			daemonize = 1;
637 			break;
638 		case 'd':
639 			usbip_use_debug = 1;
640 			break;
641 		case 'h':
642 			cmd = cmd_help;
643 			break;
644 		case 'P':
645 			pid_file = optarg ? optarg : DEFAULT_PID_FILE;
646 			break;
647 		case 't':
648 			usbip_setup_port_number(optarg);
649 			break;
650 		case 'v':
651 			cmd = cmd_version;
652 			break;
653 		case 'e':
654 			driver = &device_driver;
655 			break;
656 		case '?':
657 			usbipd_help();
658 		default:
659 			goto err_out;
660 		}
661 	}
662 
663 	if (!ipv4 && !ipv6)
664 		ipv4 = ipv6 = 1;
665 
666 	switch (cmd) {
667 	case cmd_standalone_mode:
668 		rc = do_standalone_mode(daemonize, ipv4, ipv6);
669 		remove_pid_file();
670 		break;
671 	case cmd_version:
672 		printf(PROGNAME " (%s)\n", usbip_version_string);
673 		rc = 0;
674 		break;
675 	case cmd_help:
676 		usbipd_help();
677 		rc = 0;
678 		break;
679 	default:
680 		usbipd_help();
681 		goto err_out;
682 	}
683 
684 err_out:
685 	return (rc > -1 ? EXIT_SUCCESS : EXIT_FAILURE);
686 }
687