xref: /freebsd/usr.sbin/ypserv/yp_main.c (revision b5ebd8bb4e90b810c834aabb78c87054ab84db8e)
1 /*-
2  * SPDX-License-Identifier: BSD-4-Clause
3  *
4  * Copyright (c) 1995
5  *	Bill Paul <wpaul@ctr.columbia.edu>.  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. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by Bill Paul.
18  * 4. Neither the name of the author nor the names of any co-contributors
19  *    may be used to endorse or promote products derived from this software
20  *    without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL Bill Paul OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #include <sys/cdefs.h>
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;
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
_msgout(char * msg,...)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
yp_svc_run(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
unregister(void)181 unregister(void)
182 {
183 	(void)svc_unreg(YPPROG, YPVERS);
184 	(void)svc_unreg(YPPROG, YPOLDVERS);
185 }
186 
187 static void
reaper(int sig)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 }
213 
214 static void
usage(void)215 usage(void)
216 {
217 	fprintf(stderr, "usage: ypserv [-h addr] [-d] [-n] [-p path] [-P port]\n");
218 	exit(1);
219 }
220 
221 static void
closedown(int sig)222 closedown(int sig)
223 {
224 	if (_rpcsvcstate == _IDLE) {
225 		extern fd_set svc_fdset;
226 		static int size;
227 		int i, openfd;
228 
229 		if (_rpcfdtype == SOCK_DGRAM) {
230 			unregister();
231 			exit(0);
232 		}
233 		if (size == 0) {
234 			size = getdtablesize();
235 		}
236 		for (i = 0, openfd = 0; i < size && openfd < 2; i++)
237 			if (FD_ISSET(i, &svc_fdset))
238 				openfd++;
239 		if (openfd <= 1) {
240 			unregister();
241 			exit(0);
242 		}
243 	}
244 	if (_rpcsvcstate == _SERVED)
245 		_rpcsvcstate = _IDLE;
246 
247 	(void) signal(SIGALRM, (SIG_PF) closedown);
248 	(void) alarm(_RPCSVC_CLOSEDOWN/2);
249 }
250 
251 static int
create_service(const int sock,const struct netconfig * nconf,const struct __rpc_sockinfo * si)252 create_service(const int sock, const struct netconfig *nconf,
253 	const struct __rpc_sockinfo *si)
254 {
255 	int error;
256 
257 	SVCXPRT *transp;
258 	struct addrinfo hints, *res, *res0;
259 	struct socklistent *slep;
260 	struct bindaddrlistent *blep;
261 	struct netbuf svcaddr;
262 
263 	SLIST_INIT(&sle_head);
264 	memset(&hints, 0, sizeof(hints));
265 	memset(&svcaddr, 0, sizeof(svcaddr));
266 
267 	hints.ai_family = si->si_af;
268 	hints.ai_socktype = si->si_socktype;
269 	hints.ai_protocol = si->si_proto;
270 
271 	/*
272 	 * Build socketlist from bindaddrlist.
273 	 */
274 	if (sock == RPC_ANYFD) {
275 		SLIST_FOREACH(blep, &ble_head, ble_next) {
276 			if (blep->ble_hostname == NULL)
277 				hints.ai_flags = AI_PASSIVE;
278 			else
279 				hints.ai_flags = 0;
280 			error = getaddrinfo(blep->ble_hostname, servname,
281 				    &hints, &res0);
282 			if (error) {
283 				_msgout("getaddrinfo(): %s",
284 				    gai_strerror(error));
285 				return -1;
286 			}
287 			for (res = res0; res; res = res->ai_next) {
288 				int s;
289 
290 				s = __rpc_nconf2fd(nconf);
291 				if (s < 0) {
292 					if (errno == EAFNOSUPPORT)
293 						_msgout("unsupported"
294 						    " transport: %s",
295 						    nconf->nc_netid);
296 					else
297 						_msgout("cannot create"
298 						    " %s socket: %s",
299 						    nconf->nc_netid,
300 						    strerror(errno));
301 					freeaddrinfo(res0);
302 					return -1;
303 				}
304 				if (bindresvport_sa(s, res->ai_addr) == -1) {
305 					if ((errno != EPERM) ||
306 					    (bind(s, res->ai_addr,
307 					    res->ai_addrlen) == -1)) {
308 						_msgout("cannot bind "
309 						    "%s socket: %s",
310 						    nconf->nc_netid,
311 						strerror(errno));
312 						freeaddrinfo(res0);
313 						close(sock);
314 						return -1;
315 					}
316 				}
317 				if (nconf->nc_semantics != NC_TPI_CLTS)
318 					listen(s, SOMAXCONN);
319 
320 				slep = malloc(sizeof(*slep));
321 				if (slep == NULL) {
322 					_msgout("malloc failed: %s",
323 					    strerror(errno));
324 					freeaddrinfo(res0);
325 					close(s);
326 					return -1;
327 				}
328 				memset(slep, 0, sizeof(*slep));
329 				memcpy(&slep->sle_ss, res->ai_addr,
330 				    res->ai_addrlen);
331 				slep->sle_sock = s;
332 				SLIST_INSERT_HEAD(&sle_head, slep, sle_next);
333 
334 				/*
335 				 * If servname == "0", redefine it by using
336 				 * the bound socket.
337 				 */
338 				if (strncmp("0", servname, 1) == 0) {
339 					struct sockaddr *sap;
340 					socklen_t slen;
341 					char *sname;
342 
343 					sname = malloc(NI_MAXSERV);
344 					if (sname == NULL) {
345 						_msgout("malloc(): %s",
346 						    strerror(errno));
347 						freeaddrinfo(res0);
348 						close(s);
349 						return -1;
350 					}
351 					memset(sname, 0, NI_MAXSERV);
352 
353 					sap = (struct sockaddr *)&slep->sle_ss;
354 					slen = sizeof(*sap);
355 					error = getsockname(s, sap, &slen);
356 					if (error) {
357 						_msgout("getsockname(): %s",
358 						    strerror(errno));
359 						freeaddrinfo(res0);
360 						close(s);
361 						free(sname);
362 						return -1;
363 					}
364 					error = getnameinfo(sap, slen,
365 					    NULL, 0,
366 					    sname, NI_MAXSERV,
367 					    NI_NUMERICHOST | NI_NUMERICSERV);
368 					if (error) {
369 						_msgout("getnameinfo(): %s",
370 						    strerror(errno));
371 						freeaddrinfo(res0);
372 						close(s);
373 						free(sname);
374 						return -1;
375 					}
376 					servname = sname;
377 				}
378 			}
379 			freeaddrinfo(res0);
380 		}
381 	} else {
382 		slep = malloc(sizeof(*slep));
383 		if (slep == NULL) {
384 			_msgout("malloc failed: %s", strerror(errno));
385 			return -1;
386 		}
387 		memset(slep, 0, sizeof(*slep));
388 		slep->sle_sock = sock;
389 		SLIST_INSERT_HEAD(&sle_head, slep, sle_next);
390 	}
391 
392 	/*
393 	 * Traverse socketlist and create rpc service handles for each socket.
394 	 */
395 	SLIST_FOREACH(slep, &sle_head, sle_next) {
396 		if (nconf->nc_semantics == NC_TPI_CLTS)
397 			transp = svc_dg_create(slep->sle_sock, 0, 0);
398 		else
399 			transp = svc_vc_create(slep->sle_sock, RPC_MAXDATASIZE,
400 			    RPC_MAXDATASIZE);
401 		if (transp == NULL) {
402 			_msgout("unable to create service: %s",
403 			    nconf->nc_netid);
404 			continue;
405 		}
406 		if (!svc_reg(transp, YPPROG, YPOLDVERS, ypprog_1, NULL)) {
407 			svc_destroy(transp);
408 			close(slep->sle_sock);
409 			_msgout("unable to register (YPPROG, YPOLDVERS, %s):"
410 			    " %s", nconf->nc_netid, strerror(errno));
411 			continue;
412 		}
413 		if (!svc_reg(transp, YPPROG, YPVERS, ypprog_2, NULL)) {
414 			svc_destroy(transp);
415 			close(slep->sle_sock);
416 			_msgout("unable to register (YPPROG, YPVERS, %s): %s",
417 			    nconf->nc_netid, strerror(errno));
418 			continue;
419 		}
420 	}
421 	while(!(SLIST_EMPTY(&sle_head)))
422 		SLIST_REMOVE_HEAD(&sle_head, sle_next);
423 
424 	/*
425 	 * Register RPC service to rpcbind by using AI_PASSIVE address.
426 	 */
427 	hints.ai_flags = AI_PASSIVE;
428 	error = getaddrinfo(NULL, servname, &hints, &res0);
429 	if (error) {
430 		_msgout("getaddrinfo(): %s", gai_strerror(error));
431 		return -1;
432 	}
433 	svcaddr.buf = res0->ai_addr;
434 	svcaddr.len = res0->ai_addrlen;
435 
436 	if (si->si_af == AF_INET) {
437 		/* XXX: ignore error intentionally */
438 		rpcb_set(YPPROG, YPOLDVERS, nconf, &svcaddr);
439 	}
440 	/* XXX: ignore error intentionally */
441 	rpcb_set(YPPROG, YPVERS, nconf, &svcaddr);
442 	freeaddrinfo(res0);
443 	return 0;
444 }
445 
446 int
main(int argc,char * argv[])447 main(int argc, char *argv[])
448 {
449 	int ch;
450 	int error;
451 	int ntrans;
452 
453 	void *nc_handle;
454 	struct netconfig *nconf;
455 	struct __rpc_sockinfo si;
456 	struct bindaddrlistent *blep;
457 
458 	memset(&si, 0, sizeof(si));
459 	SLIST_INIT(&ble_head);
460 
461 	while ((ch = getopt(argc, argv, "dh:np:P:")) != -1) {
462 		switch (ch) {
463 		case 'd':
464 			debug = ypdb_debug = 1;
465 			break;
466 		case 'h':
467 			blep = malloc(sizeof(*blep));
468 			if (blep == NULL)
469 				err(1, "malloc() failed: -h %s", optarg);
470 			blep->ble_hostname = optarg;
471 			SLIST_INSERT_HEAD(&ble_head, blep, ble_next);
472 			break;
473 		case 'n':
474 			do_dns = 1;
475 			break;
476 		case 'p':
477 			yp_dir = optarg;
478 			break;
479 		case 'P':
480 			servname = optarg;
481 			break;
482 		default:
483 			usage();
484 		}
485 	}
486 	/*
487 	 * Add "anyaddr" entry if no -h is specified.
488 	 */
489 	if (SLIST_EMPTY(&ble_head)) {
490 		blep = malloc(sizeof(*blep));
491 		if (blep == NULL)
492 			err(1, "malloc() failed");
493 		memset(blep, 0, sizeof(*blep));
494 		SLIST_INSERT_HEAD(&ble_head, blep, ble_next);
495 	}
496 
497 	load_securenets();
498 	yp_init_resolver();
499 #ifdef DB_CACHE
500 	yp_init_dbs();
501 #endif
502 	nc_handle = setnetconfig();
503 	if (nc_handle == NULL)
504 		err(1, "cannot read %s", NETCONFIG);
505 	if (__rpc_fd2sockinfo(0, &si) != 0) {
506 		/* invoked from inetd */
507 		_rpcpmstart = 1;
508 		_rpcfdtype = si.si_socktype;
509 		_rpcaf = si.si_af;
510 		_rpcfd = 0;
511 		openlog("ypserv", LOG_PID, LOG_DAEMON);
512 	} else {
513 		/* standalone mode */
514 		if (!debug) {
515 			if (daemon(0,0)) {
516 				err(1,"cannot fork");
517 			}
518 			openlog("ypserv", LOG_PID, LOG_DAEMON);
519 		}
520 		_rpcpmstart = 0;
521 		_rpcaf = AF_INET;
522 		_rpcfd = RPC_ANYFD;
523 		unregister();
524 	}
525 
526 	if (madvise(NULL, 0, MADV_PROTECT) != 0)
527 		_msgout("madvise(): %s", strerror(errno));
528 
529 	/*
530 	 * Create RPC service for each transport.
531 	 */
532 	ntrans = 0;
533 	while((nconf = getnetconfig(nc_handle))) {
534 		if ((nconf->nc_flag & NC_VISIBLE)) {
535 			if (__rpc_nconf2sockinfo(nconf, &si) == 0) {
536 				_msgout("cannot get information for %s.  "
537 				    "Ignored.", nconf->nc_netid);
538 				continue;
539 			}
540 			if (_rpcpmstart) {
541 				if (si.si_socktype != _rpcfdtype ||
542 				    si.si_af != _rpcaf)
543 					continue;
544 			} else if (si.si_af != _rpcaf)
545 					continue;
546 			error = create_service(_rpcfd, nconf, &si);
547 			if (error) {
548 				endnetconfig(nc_handle);
549 				exit(1);
550 			}
551 			ntrans++;
552 		}
553 	}
554 	endnetconfig(nc_handle);
555 	while(!(SLIST_EMPTY(&ble_head)))
556 		SLIST_REMOVE_HEAD(&ble_head, ble_next);
557 	if (ntrans == 0) {
558 		_msgout("no transport is available.  Aborted.");
559 		exit(1);
560 	}
561 	if (_rpcpmstart) {
562 		(void) signal(SIGALRM, (SIG_PF) closedown);
563 		(void) alarm(_RPCSVC_CLOSEDOWN/2);
564 	}
565 /*
566  * Make sure SIGPIPE doesn't blow us away while servicing TCP
567  * connections.
568  */
569 	(void) signal(SIGPIPE, SIG_IGN);
570 	(void) signal(SIGCHLD, (SIG_PF) reaper);
571 	(void) signal(SIGTERM, (SIG_PF) reaper);
572 	(void) signal(SIGINT, (SIG_PF) reaper);
573 	(void) signal(SIGHUP, (SIG_PF) reaper);
574 	yp_svc_run();
575 	_msgout("svc_run returned");
576 	exit(1);
577 	/* NOTREACHED */
578 }
579