xref: /freebsd/usr.sbin/ypserv/yp_main.c (revision 325151a3)
1 /*
2  * Copyright (c) 1995
3  *	Bill Paul <wpaul@ctr.columbia.edu>.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
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. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by Bill Paul.
16  * 4. Neither the name of the author nor the names of any co-contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL Bill Paul OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 /*
37  * ypserv startup function.
38  * We need out own main() since we have to do some additional work
39  * that rpcgen won't do for us. Most of this file was generated using
40  * rpcgen.new, and later modified.
41  */
42 
43 #include <sys/types.h>
44 #include <sys/mman.h>
45 #include <sys/queue.h>
46 #include <sys/socket.h>
47 #include <sys/wait.h>
48 #include "yp.h"
49 #include <err.h>
50 #include <errno.h>
51 #include <memory.h>
52 #include <stdio.h>
53 #include <signal.h>
54 #include <stdarg.h>
55 #include <stdlib.h> /* getenv, exit */
56 #include <string.h> /* strcmp */
57 #include <syslog.h>
58 #include <unistd.h>
59 #ifdef __cplusplus
60 #include <sysent.h> /* getdtablesize, open */
61 #endif /* __cplusplus */
62 #include <netinet/in.h>
63 #include <netdb.h>
64 #include "yp_extern.h"
65 #include <netconfig.h>
66 #include <rpc/rpc.h>
67 #include <rpc/rpc_com.h>
68 
69 #ifndef SIG_PF
70 #define	SIG_PF void(*)(int)
71 #endif
72 
73 #define	_RPCSVC_CLOSEDOWN 120
74 int _rpcpmstart;		/* Started by a port monitor ? */
75 static int _rpcfdtype;  /* Whether Stream or Datagram? */
76 static int _rpcaf;
77 static int _rpcfd;
78 
79 /* States a server can be in wrt request */
80 #define	_IDLE 0
81 #define	_SERVED 1
82 #define	_SERVING 2
83 
84 extern void ypprog_1(struct svc_req *, SVCXPRT *);
85 extern void ypprog_2(struct svc_req *, SVCXPRT *);
86 extern int _rpc_dtablesize(void);
87 extern int _rpcsvcstate;	 /* Set when a request is serviced */
88 char *progname = "ypserv";
89 char *yp_dir = _PATH_YP;
90 /*int debug = 0;*/
91 int do_dns = 0;
92 int resfd;
93 
94 struct socklistent {
95 	int				sle_sock;
96 	struct sockaddr_storage		sle_ss;
97 	SLIST_ENTRY(socklistent)	sle_next;
98 };
99 static SLIST_HEAD(, socklistent) sle_head =
100 	SLIST_HEAD_INITIALIZER(sle_head);
101 
102 struct bindaddrlistent {
103 	const char			*ble_hostname;
104 	SLIST_ENTRY(bindaddrlistent)	ble_next;
105 };
106 static SLIST_HEAD(, bindaddrlistent) ble_head =
107 	SLIST_HEAD_INITIALIZER(ble_head);
108 
109 static char *servname = "0";
110 
111 static
112 void _msgout(char* msg, ...)
113 {
114 	va_list ap;
115 
116 	va_start(ap, msg);
117 	if (debug) {
118 		if (_rpcpmstart)
119 			vsyslog(LOG_ERR, msg, ap);
120 		else
121 			vwarnx(msg, ap);
122 	} else
123 		vsyslog(LOG_ERR, msg, ap);
124 	va_end(ap);
125 }
126 
127 pid_t	yp_pid;
128 
129 static void
130 yp_svc_run(void)
131 {
132 #ifdef FD_SETSIZE
133 	fd_set readfds;
134 #else
135 	int readfds;
136 #endif /* def FD_SETSIZE */
137 	int fd_setsize = _rpc_dtablesize();
138 	struct timeval timeout;
139 
140 	/* Establish the identity of the parent ypserv process. */
141 	yp_pid = getpid();
142 
143 	for (;;) {
144 #ifdef FD_SETSIZE
145 		readfds = svc_fdset;
146 #else
147 		readfds = svc_fds;
148 #endif /* def FD_SETSIZE */
149 
150 		FD_SET(resfd, &readfds);
151 
152 		timeout.tv_sec = RESOLVER_TIMEOUT;
153 		timeout.tv_usec = 0;
154 		switch (select(fd_setsize, &readfds, NULL, NULL,
155 			       &timeout)) {
156 		case -1:
157 			if (errno == EINTR) {
158 				continue;
159 			}
160 			warn("svc_run: - select failed");
161 			return;
162 		case 0:
163 			if (getpid() == yp_pid)
164 				yp_prune_dnsq();
165 			break;
166 		default:
167 			if (getpid() == yp_pid) {
168 				if (FD_ISSET(resfd, &readfds)) {
169 					yp_run_dnsq();
170 					FD_CLR(resfd, &readfds);
171 				}
172 				svc_getreqset(&readfds);
173 			}
174 		}
175 		if (yp_pid != getpid())
176 			_exit(0);
177 	}
178 }
179 
180 static void
181 unregister(void)
182 {
183 	(void)svc_unreg(YPPROG, YPVERS);
184 	(void)svc_unreg(YPPROG, YPOLDVERS);
185 }
186 
187 static void
188 reaper(int sig)
189 {
190 	int			status;
191 	int			saved_errno;
192 
193 	saved_errno = errno;
194 
195 	if (sig == SIGHUP) {
196 		load_securenets();
197 #ifdef DB_CACHE
198 		yp_flush_all();
199 #endif
200 		errno = saved_errno;
201 		return;
202 	}
203 
204 	if (sig == SIGCHLD) {
205 		while (wait3(&status, WNOHANG, NULL) > 0)
206 			children--;
207 	} else {
208 		unregister();
209 		exit(0);
210 	}
211 	errno = saved_errno;
212 	return;
213 }
214 
215 static void
216 usage(void)
217 {
218 	fprintf(stderr, "usage: ypserv [-h addr] [-d] [-n] [-p path] [-P port]\n");
219 	exit(1);
220 }
221 
222 static void
223 closedown(int sig)
224 {
225 	if (_rpcsvcstate == _IDLE) {
226 		extern fd_set svc_fdset;
227 		static int size;
228 		int i, openfd;
229 
230 		if (_rpcfdtype == SOCK_DGRAM) {
231 			unregister();
232 			exit(0);
233 		}
234 		if (size == 0) {
235 			size = getdtablesize();
236 		}
237 		for (i = 0, openfd = 0; i < size && openfd < 2; i++)
238 			if (FD_ISSET(i, &svc_fdset))
239 				openfd++;
240 		if (openfd <= 1) {
241 			unregister();
242 			exit(0);
243 		}
244 	}
245 	if (_rpcsvcstate == _SERVED)
246 		_rpcsvcstate = _IDLE;
247 
248 	(void) signal(SIGALRM, (SIG_PF) closedown);
249 	(void) alarm(_RPCSVC_CLOSEDOWN/2);
250 }
251 
252 static int
253 create_service(const int sock, const struct netconfig *nconf,
254 	const struct __rpc_sockinfo *si)
255 {
256 	int error;
257 
258 	SVCXPRT *transp;
259 	struct addrinfo hints, *res, *res0;
260 	struct socklistent *slep;
261 	struct bindaddrlistent *blep;
262 	struct netbuf svcaddr;
263 
264 	SLIST_INIT(&sle_head);
265 	memset(&hints, 0, sizeof(hints));
266 	memset(&svcaddr, 0, sizeof(svcaddr));
267 
268 	hints.ai_family = si->si_af;
269 	hints.ai_socktype = si->si_socktype;
270 	hints.ai_protocol = si->si_proto;
271 
272 	/*
273 	 * Build socketlist from bindaddrlist.
274 	 */
275 	if (sock == RPC_ANYFD) {
276 		SLIST_FOREACH(blep, &ble_head, ble_next) {
277 			if (blep->ble_hostname == NULL)
278 				hints.ai_flags = AI_PASSIVE;
279 			else
280 				hints.ai_flags = 0;
281 			error = getaddrinfo(blep->ble_hostname, servname,
282 				    &hints, &res0);
283 			if (error) {
284 				_msgout("getaddrinfo(): %s",
285 				    gai_strerror(error));
286 				return -1;
287 			}
288 			for (res = res0; res; res = res->ai_next) {
289 				int s;
290 
291 				s = __rpc_nconf2fd(nconf);
292 				if (s < 0) {
293 					if (errno == EAFNOSUPPORT)
294 						_msgout("unsupported"
295 						    " transport: %s",
296 						    nconf->nc_netid);
297 					else
298 						_msgout("cannot create"
299 						    " %s socket: %s",
300 						    nconf->nc_netid,
301 						    strerror(errno));
302 					freeaddrinfo(res0);
303 					return -1;
304 				}
305 				if (bindresvport_sa(s, res->ai_addr) == -1) {
306 					if ((errno != EPERM) ||
307 					    (bind(s, res->ai_addr,
308 					    res->ai_addrlen) == -1)) {
309 						_msgout("cannot bind "
310 						    "%s socket: %s",
311 						    nconf->nc_netid,
312 						strerror(errno));
313 						freeaddrinfo(res0);
314 						close(sock);
315 						return -1;
316 					}
317 				}
318 				if (nconf->nc_semantics != NC_TPI_CLTS)
319 					listen(s, SOMAXCONN);
320 
321 				slep = malloc(sizeof(*slep));
322 				if (slep == NULL) {
323 					_msgout("malloc failed: %s",
324 					    strerror(errno));
325 					freeaddrinfo(res0);
326 					close(s);
327 					return -1;
328 				}
329 				memset(slep, 0, sizeof(*slep));
330 				memcpy(&slep->sle_ss, res->ai_addr,
331 				    res->ai_addrlen);
332 				slep->sle_sock = s;
333 				SLIST_INSERT_HEAD(&sle_head, slep, sle_next);
334 
335 				/*
336 				 * If servname == "0", redefine it by using
337 				 * the bound socket.
338 				 */
339 				if (strncmp("0", servname, 1) == 0) {
340 					struct sockaddr *sap;
341 					socklen_t slen;
342 					char *sname;
343 
344 					sname = malloc(NI_MAXSERV);
345 					if (sname == NULL) {
346 						_msgout("malloc(): %s",
347 						    strerror(errno));
348 						freeaddrinfo(res0);
349 						close(s);
350 						return -1;
351 					}
352 					memset(sname, 0, NI_MAXSERV);
353 
354 					sap = (struct sockaddr *)&slep->sle_ss;
355 					slen = sizeof(*sap);
356 					error = getsockname(s, sap, &slen);
357 					if (error) {
358 						_msgout("getsockname(): %s",
359 						    strerror(errno));
360 						freeaddrinfo(res0);
361 						close(s);
362 						free(sname);
363 						return -1;
364 					}
365 					error = getnameinfo(sap, slen,
366 					    NULL, 0,
367 					    sname, NI_MAXSERV,
368 					    NI_NUMERICHOST | NI_NUMERICSERV);
369 					if (error) {
370 						_msgout("getnameinfo(): %s",
371 						    strerror(errno));
372 						freeaddrinfo(res0);
373 						close(s);
374 						free(sname);
375 						return -1;
376 					}
377 					servname = sname;
378 				}
379 			}
380 			freeaddrinfo(res0);
381 		}
382 	} else {
383 		slep = malloc(sizeof(*slep));
384 		if (slep == NULL) {
385 			_msgout("malloc failed: %s", strerror(errno));
386 			return -1;
387 		}
388 		memset(slep, 0, sizeof(*slep));
389 		slep->sle_sock = sock;
390 		SLIST_INSERT_HEAD(&sle_head, slep, sle_next);
391 	}
392 
393 	/*
394 	 * Traverse socketlist and create rpc service handles for each socket.
395 	 */
396 	SLIST_FOREACH(slep, &sle_head, sle_next) {
397 		if (nconf->nc_semantics == NC_TPI_CLTS)
398 			transp = svc_dg_create(slep->sle_sock, 0, 0);
399 		else
400 			transp = svc_vc_create(slep->sle_sock, RPC_MAXDATASIZE,
401 			    RPC_MAXDATASIZE);
402 		if (transp == NULL) {
403 			_msgout("unable to create service: %s",
404 			    nconf->nc_netid);
405 			continue;
406 		}
407 		if (!svc_reg(transp, YPPROG, YPOLDVERS, ypprog_1, NULL)) {
408 			svc_destroy(transp);
409 			close(slep->sle_sock);
410 			_msgout("unable to register (YPPROG, YPOLDVERS, %s):"
411 			    " %s", nconf->nc_netid, strerror(errno));
412 			continue;
413 		}
414 		if (!svc_reg(transp, YPPROG, YPVERS, ypprog_2, NULL)) {
415 			svc_destroy(transp);
416 			close(slep->sle_sock);
417 			_msgout("unable to register (YPPROG, YPVERS, %s): %s",
418 			    nconf->nc_netid, strerror(errno));
419 			continue;
420 		}
421 	}
422 	while(!(SLIST_EMPTY(&sle_head)))
423 		SLIST_REMOVE_HEAD(&sle_head, sle_next);
424 
425 	/*
426 	 * Register RPC service to rpcbind by using AI_PASSIVE address.
427 	 */
428 	hints.ai_flags = AI_PASSIVE;
429 	error = getaddrinfo(NULL, servname, &hints, &res0);
430 	if (error) {
431 		_msgout("getaddrinfo(): %s", gai_strerror(error));
432 		return -1;
433 	}
434 	svcaddr.buf = res0->ai_addr;
435 	svcaddr.len = res0->ai_addrlen;
436 
437 	if (si->si_af == AF_INET) {
438 		/* XXX: ignore error intentionally */
439 		rpcb_set(YPPROG, YPOLDVERS, nconf, &svcaddr);
440 	}
441 	/* XXX: ignore error intentionally */
442 	rpcb_set(YPPROG, YPVERS, nconf, &svcaddr);
443 	freeaddrinfo(res0);
444 	return 0;
445 }
446 
447 int
448 main(int argc, char *argv[])
449 {
450 	int ch;
451 	int error;
452 	int ntrans;
453 
454 	void *nc_handle;
455 	struct netconfig *nconf;
456 	struct __rpc_sockinfo si;
457 	struct bindaddrlistent *blep;
458 
459 	memset(&si, 0, sizeof(si));
460 	SLIST_INIT(&ble_head);
461 
462 	while ((ch = getopt(argc, argv, "dh:np:P:")) != -1) {
463 		switch (ch) {
464 		case 'd':
465 			debug = ypdb_debug = 1;
466 			break;
467 		case 'h':
468 			blep = malloc(sizeof(*blep));
469 			if (blep == NULL)
470 				err(1, "malloc() failed: -h %s", optarg);
471 			blep->ble_hostname = optarg;
472 			SLIST_INSERT_HEAD(&ble_head, blep, ble_next);
473 			break;
474 		case 'n':
475 			do_dns = 1;
476 			break;
477 		case 'p':
478 			yp_dir = optarg;
479 			break;
480 		case 'P':
481 			servname = optarg;
482 			break;
483 		default:
484 			usage();
485 		}
486 	}
487 	/*
488 	 * Add "anyaddr" entry if no -h is specified.
489 	 */
490 	if (SLIST_EMPTY(&ble_head)) {
491 		blep = malloc(sizeof(*blep));
492 		if (blep == NULL)
493 			err(1, "malloc() failed");
494 		memset(blep, 0, sizeof(*blep));
495 		SLIST_INSERT_HEAD(&ble_head, blep, ble_next);
496 	}
497 
498 	load_securenets();
499 	yp_init_resolver();
500 #ifdef DB_CACHE
501 	yp_init_dbs();
502 #endif
503 	nc_handle = setnetconfig();
504 	if (nc_handle == NULL)
505 		err(1, "cannot read %s", NETCONFIG);
506 	if (__rpc_fd2sockinfo(0, &si) != 0) {
507 		/* invoked from inetd */
508 		_rpcpmstart = 1;
509 		_rpcfdtype = si.si_socktype;
510 		_rpcaf = si.si_af;
511 		_rpcfd = 0;
512 		openlog("ypserv", LOG_PID, LOG_DAEMON);
513 	} else {
514 		/* standalone mode */
515 		if (!debug) {
516 			if (daemon(0,0)) {
517 				err(1,"cannot fork");
518 			}
519 			openlog("ypserv", LOG_PID, LOG_DAEMON);
520 		}
521 		_rpcpmstart = 0;
522 		_rpcaf = AF_INET;
523 		_rpcfd = RPC_ANYFD;
524 		unregister();
525 	}
526 
527 	if (madvise(NULL, 0, MADV_PROTECT) != 0)
528 		_msgout("madvise(): %s", strerror(errno));
529 
530 	/*
531 	 * Create RPC service for each transport.
532 	 */
533 	ntrans = 0;
534 	while((nconf = getnetconfig(nc_handle))) {
535 		if ((nconf->nc_flag & NC_VISIBLE)) {
536 			if (__rpc_nconf2sockinfo(nconf, &si) == 0) {
537 				_msgout("cannot get information for %s.  "
538 				    "Ignored.", nconf->nc_netid);
539 				continue;
540 			}
541 			if (_rpcpmstart) {
542 				if (si.si_socktype != _rpcfdtype ||
543 				    si.si_af != _rpcaf)
544 					continue;
545 			} else if (si.si_af != _rpcaf)
546 					continue;
547 			error = create_service(_rpcfd, nconf, &si);
548 			if (error) {
549 				endnetconfig(nc_handle);
550 				exit(1);
551 			}
552 			ntrans++;
553 		}
554 	}
555 	endnetconfig(nc_handle);
556 	while(!(SLIST_EMPTY(&ble_head)))
557 		SLIST_REMOVE_HEAD(&ble_head, ble_next);
558 	if (ntrans == 0) {
559 		_msgout("no transport is available.  Aborted.");
560 		exit(1);
561 	}
562 	if (_rpcpmstart) {
563 		(void) signal(SIGALRM, (SIG_PF) closedown);
564 		(void) alarm(_RPCSVC_CLOSEDOWN/2);
565 	}
566 /*
567  * Make sure SIGPIPE doesn't blow us away while servicing TCP
568  * connections.
569  */
570 	(void) signal(SIGPIPE, SIG_IGN);
571 	(void) signal(SIGCHLD, (SIG_PF) reaper);
572 	(void) signal(SIGTERM, (SIG_PF) reaper);
573 	(void) signal(SIGINT, (SIG_PF) reaper);
574 	(void) signal(SIGHUP, (SIG_PF) reaper);
575 	yp_svc_run();
576 	_msgout("svc_run returned");
577 	exit(1);
578 	/* NOTREACHED */
579 }
580