xref: /netbsd/usr.sbin/ypserv/ypserv/ypserv.c (revision c4a72b64)
1 /*	$NetBSD: ypserv.c,v 1.18 2002/07/06 00:42:27 wiz Exp $	*/
2 
3 /*
4  * Copyright (c) 1994 Mats O Jansson <moj@stacken.kth.se>
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  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by Mats O Jansson
18  * 4. The name of the author may not be used to endorse or promote products
19  *    derived from this software without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS
22  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
23  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
25  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #include <sys/cdefs.h>
35 #ifndef lint
36 __RCSID("$NetBSD: ypserv.c,v 1.18 2002/07/06 00:42:27 wiz Exp $");
37 #endif
38 
39 #include <sys/types.h>
40 #include <sys/socket.h>
41 #include <sys/wait.h>
42 
43 #include <err.h>
44 #include <netdb.h>
45 #include <signal.h>
46 #include <stdio.h>
47 #include <stdlib.h>
48 #include <string.h>
49 #include <syslog.h>
50 #include <unistd.h>
51 #include <util.h>
52 
53 #include <rpc/rpc.h>
54 #include <rpc/xdr.h>
55 #include <rpc/pmap_clnt.h>
56 
57 #include <rpcsvc/yp_prot.h>
58 
59 #include "ypdef.h"
60 #include "ypserv.h"
61 
62 #ifdef LIBWRAP
63 #include <tcpd.h>
64 
65 int allow_severity = LOG_DAEMON | LOG_INFO;
66 int deny_severity = LOG_DAEMON | LOG_WARNING;
67 
68 /* XXX For ypserv_proc.c -- NOT THREAD SAFE!  (like any of this code is) */
69 const char *clientstr;
70 const char *svcname;
71 #endif /* LIBWRAP */
72 
73 int	usedns;
74 #ifdef DEBUG
75 int	foreground = 1;
76 #else
77 int	foreground;
78 #endif
79 
80 #ifdef LIBWRAP
81 int	lflag;
82 #endif
83 
84 int	main(int, char *[]);
85 void	usage(void);
86 
87 void	sighandler(int);
88 
89 
90 static
91 void _msgout(int level, const char *msg)
92 {
93 	if (foreground)
94                 warnx("%s", msg);
95         else
96                 syslog(level, "%s", msg);
97 }
98 
99 static void
100 ypprog_2(struct svc_req *rqstp, SVCXPRT *transp)
101 {
102 	union {
103 		char * ypproc_domain_2_arg;
104 		char * ypproc_domain_nonack_2_arg;
105 		struct ypreq_key ypproc_match_2_arg;
106 		struct ypreq_nokey ypproc_first_2_arg;
107 		struct ypreq_key ypproc_next_2_arg;
108 		struct ypreq_xfr ypproc_xfr_2_arg;
109 		struct ypreq_nokey ypproc_all_2_arg;
110 		struct ypreq_nokey ypproc_master_2_arg;
111 		struct ypreq_nokey ypproc_order_2_arg;
112 		char * ypproc_maplist_2_arg;
113 	} argument;
114 	char *result;
115 	xdrproc_t xdr_argument, xdr_result;
116 	void *(*local)(void *, struct svc_req *);
117 #ifdef LIBWRAP
118 	struct request_info req;
119 	struct sockaddr *caller;
120 #define	SVCNAME(x)	svcname = x
121 #else
122 #define	SVCNAME(x)	/* nothing */
123 #endif
124 
125 #ifdef LIBWRAP
126 	caller = svc_getrpccaller(transp)->buf;
127 	request_init(&req, RQ_DAEMON, getprogname(), RQ_CLIENT_SIN, caller,
128 	    NULL);
129 	sock_methods(&req);
130 #endif
131 
132 	switch (rqstp->rq_proc) {
133 	case YPPROC_NULL:
134 		xdr_argument = xdr_void;
135 		xdr_result = xdr_void;
136 		local = ypproc_null_2_svc;
137 		SVCNAME("null_2");
138 		break;
139 
140 	case YPPROC_DOMAIN:
141 		xdr_argument = xdr_ypdomain_wrap_string;
142 		xdr_result = xdr_bool;
143 		local = ypproc_domain_2_svc;
144 		SVCNAME("domain_2");
145 		break;
146 
147 	case YPPROC_DOMAIN_NONACK:
148 		xdr_argument = xdr_ypdomain_wrap_string;
149 		xdr_result = xdr_bool;
150 		local = ypproc_domain_nonack_2_svc;
151 		SVCNAME("domain_nonack_2");
152 		break;
153 
154 	case YPPROC_MATCH:
155 		xdr_argument = xdr_ypreq_key;
156 		xdr_result = xdr_ypresp_val;
157 		local = ypproc_match_2_svc;
158 		SVCNAME("match_2");
159 		break;
160 
161 	case YPPROC_FIRST:
162 		xdr_argument = xdr_ypreq_nokey;
163 		xdr_result = xdr_ypresp_key_val;
164 		local = ypproc_first_2_svc;
165 		SVCNAME("first_2");
166 		break;
167 
168 	case YPPROC_NEXT:
169 		xdr_argument = xdr_ypreq_key;
170 		xdr_result = xdr_ypresp_key_val;
171 		local = ypproc_next_2_svc;
172 		SVCNAME("next_2");
173 		break;
174 
175 	case YPPROC_XFR:
176 		xdr_argument = xdr_ypreq_xfr;
177 		xdr_result = xdr_ypresp_xfr;
178 		local = ypproc_xfr_2_svc;
179 		SVCNAME("xfer_2");
180 		break;
181 
182 	case YPPROC_CLEAR:
183 		xdr_argument = xdr_void;
184 		xdr_result = xdr_void;
185 		local = ypproc_clear_2_svc;
186 		SVCNAME("clear_2");
187 		break;
188 
189 	case YPPROC_ALL:
190 		xdr_argument = xdr_ypreq_nokey;
191 		xdr_result = xdr_ypresp_all;
192 		local = ypproc_all_2_svc;
193 		SVCNAME("all_2");
194 		break;
195 
196 	case YPPROC_MASTER:
197 		xdr_argument = xdr_ypreq_nokey;
198 		xdr_result = xdr_ypresp_master;
199 		local = ypproc_master_2_svc;
200 		SVCNAME("master_2");
201 		break;
202 
203 	case YPPROC_ORDER:
204 		xdr_argument = xdr_ypreq_nokey;
205 		xdr_result = xdr_ypresp_order;
206 		local = ypproc_order_2_svc;
207 		SVCNAME("order_2");
208 		break;
209 
210 	case YPPROC_MAPLIST:
211 		xdr_argument = xdr_ypdomain_wrap_string;
212 		xdr_result = xdr_ypresp_maplist;
213 		local = ypproc_maplist_2_svc;
214 		SVCNAME("maplist_2");
215 		break;
216 
217 	default:
218 		svcerr_noproc(transp);
219 		return;
220 	}
221 
222 #ifdef LIBWRAP
223 	clientstr = eval_client(&req);
224 
225 	if (hosts_access(&req) == 0) {
226 		syslog(deny_severity,
227 		    "%s: refused request from %.500s", svcname, clientstr);
228 		svcerr_auth(transp, AUTH_FAILED);
229 		return;
230 	}
231 #endif
232 
233 	(void) memset((char *)&argument, 0, sizeof (argument));
234 	if (!svc_getargs(transp, xdr_argument, (caddr_t) &argument)) {
235 		svcerr_decode(transp);
236 		return;
237 	}
238 	result = (*local)(&argument, rqstp);
239 	if (result != NULL && !svc_sendreply(transp, xdr_result, result)) {
240 		svcerr_systemerr(transp);
241 	}
242 	if (!svc_freeargs(transp, xdr_argument, (caddr_t) &argument)) {
243 		_msgout(LOG_ERR, "unable to free arguments");
244 		exit(1);
245 	}
246 	return;
247 }
248 
249 /*
250  * limited NIS version 1 support: the null, domain, and domain_nonack
251  * request/reply format is identical between v1 and v2.  SunOS4's ypbind
252  * makes v1 domain_nonack calls.
253  */
254 static void
255 ypprog_1(struct svc_req *rqstp, SVCXPRT *transp)
256 {
257 	switch (rqstp->rq_proc) {
258 	case YPPROC_NULL:
259 	case YPPROC_DOMAIN:
260 	case YPPROC_DOMAIN_NONACK:
261 		ypprog_2(rqstp, transp);
262 		return;
263 
264 	default:
265 		svcerr_noproc(transp);
266 		return;
267 	}
268 }
269 
270 int
271 main(int argc, char *argv[])
272 {
273 	SVCXPRT *udptransp, *tcptransp, *udp6transp, *tcp6transp;
274 	struct netconfig *udpconf, *tcpconf, *udp6conf, *tcp6conf;
275 	int udpsock, tcpsock, udp6sock, tcp6sock;
276 	struct sigaction sa;
277 	int ch, xcreated = 0, one = 1;
278 
279 #ifdef LIBWRAP
280 #define	GETOPTSTR	"dfl"
281 #else
282 #define	GETOPTSTR	"df"
283 #endif
284 
285 	while ((ch = getopt(argc, argv, GETOPTSTR)) != -1) {
286 		switch (ch) {
287 		case 'd':
288 			usedns = 1;
289 			break;
290 		case 'f':
291 			foreground = 1;
292 			break;
293 
294 #ifdef LIBWRAP
295 		case 'l':
296 			lflag = 1;
297 			break;
298 #endif
299 		default:
300 			usage();
301 		}
302 	}
303 
304 #undef GETOPTSTR
305 
306 	/* This program must be run by root. */
307 	if (geteuid() != 0)
308 		errx(1, "must run as root");
309 
310 	if (foreground == 0 && daemon(0, 0))
311 		err(1, "can't detach");
312 
313 	openlog("ypserv", LOG_PID, LOG_DAEMON);
314 	syslog(LOG_INFO, "starting");
315 	pidfile(NULL);
316 
317 	(void) rpcb_unset(YPPROG, YPVERS, NULL);
318 	(void) rpcb_unset(YPPROG, YPVERS_ORIG, NULL);
319 
320 	udpsock  = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
321 	tcpsock  = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
322 	udp6sock = socket(AF_INET6, SOCK_DGRAM, IPPROTO_UDP);
323 	tcp6sock = socket(AF_INET6, SOCK_STREAM, IPPROTO_TCP);
324 
325 	/*
326 	 * We're doing host-based access checks here, so don't allow
327 	 * v4-in-v6 to confuse things.
328 	 */
329 	if (udp6sock != -1 && setsockopt(udp6sock, IPPROTO_IPV6,
330 	    IPV6_V6ONLY, &one, sizeof(one)) < 0) {
331 		_msgout(LOG_ERR, "can't disable v4-in-v6 on UDP socket");
332 		exit(1);
333 	}
334 	if (tcp6sock != -1 && setsockopt(tcp6sock, IPPROTO_IPV6,
335 	    IPV6_V6ONLY, &one, sizeof(one)) < 0) {
336 		_msgout(LOG_ERR, "can't disable v4-in-v6 on TCP socket");
337 		exit(1);
338 	}
339 
340 	ypdb_init();	/* init db stuff */
341 
342 	sa.sa_handler = sighandler;
343 	sa.sa_flags = 0;
344 	if (sigemptyset(&sa.sa_mask)) {
345 		_msgout(LOG_ERR, "sigemptyset: %m");
346 		exit(1);
347 	}
348 	if (sigaction(SIGCHLD, &sa, NULL)) {
349 		_msgout(LOG_ERR, "sigaction: %m");
350 		exit(1);
351 	}
352 
353 	udpconf  = getnetconfigent("udp");
354 	tcpconf  = getnetconfigent("tcp");
355 	udp6conf = getnetconfigent("udp6");
356 	tcp6conf = getnetconfigent("tcp6");
357 
358 	if (udpsock != -1 && udpconf != NULL) {
359 		if (bindresvport(udpsock, NULL) == 0) {
360 			udptransp = svc_dg_create(udpsock, 0, 0);
361 			if (udptransp != NULL) {
362 				if (svc_reg(udptransp, YPPROG, YPVERS_ORIG,
363 					    ypprog_1, udpconf) == 0 ||
364 				    svc_reg(udptransp, YPPROG, YPVERS,
365 					    ypprog_2, udpconf) == 0)
366 					_msgout(LOG_WARNING,
367 					    "unable to register UDP service");
368 				else
369 					xcreated++;
370 			} else
371 				_msgout(LOG_WARNING,
372 				    "unable to create UDP service");
373 		} else
374 			_msgout(LOG_ERR, "unable to bind reserved UDP port");
375 		freenetconfigent(udpconf);
376 	}
377 
378 	if (tcpsock != -1 && tcpconf != NULL) {
379 		if (bindresvport(tcpsock, NULL) == 0) {
380 			listen(tcpsock, SOMAXCONN);
381 			tcptransp = svc_vc_create(tcpsock, 0, 0);
382 			if (tcptransp != NULL) {
383 				if (svc_reg(tcptransp, YPPROG, YPVERS_ORIG,
384 					    ypprog_1, tcpconf) == 0 ||
385 				    svc_reg(tcptransp, YPPROG, YPVERS,
386 					    ypprog_2, tcpconf) == 0)
387 					_msgout(LOG_WARNING,
388 					    "unable to register TCP service");
389 				else
390 					xcreated++;
391 			} else
392 				_msgout(LOG_WARNING,
393 				    "unable to create TCP service");
394 		} else
395 			_msgout(LOG_ERR, "unable to bind reserved TCP port");
396 		freenetconfigent(tcpconf);
397 	}
398 
399 	if (udp6sock != -1 && udp6conf != NULL) {
400 		if (bindresvport(udp6sock, NULL) == 0) {
401 			udp6transp = svc_dg_create(udp6sock, 0, 0);
402 			if (udp6transp != NULL) {
403 				if (svc_reg(udp6transp, YPPROG, YPVERS_ORIG,
404 					    ypprog_1, udp6conf) == 0 ||
405 				    svc_reg(udp6transp, YPPROG, YPVERS,
406 					    ypprog_2, udp6conf) == 0)
407 					_msgout(LOG_WARNING,
408 					    "unable to register UDP6 service");
409 				else
410 					xcreated++;
411 			} else
412 				_msgout(LOG_WARNING,
413 				    "unable to create UDP6 service");
414 		} else
415 			_msgout(LOG_ERR, "unable to bind reserved UDP6 port");
416 		freenetconfigent(udp6conf);
417 	}
418 
419 	if (tcp6sock != -1 && tcp6conf != NULL) {
420 		if (bindresvport(tcp6sock, NULL) == 0) {
421 			listen(tcp6sock, SOMAXCONN);
422 			tcp6transp = svc_vc_create(tcp6sock, 0, 0);
423 			if (tcp6transp != NULL) {
424 				if (svc_reg(tcp6transp, YPPROG, YPVERS_ORIG,
425 					    ypprog_1, tcp6conf) == 0 ||
426 				    svc_reg(tcp6transp,  YPPROG, YPVERS,
427 					    ypprog_2, tcp6conf) == 0)
428 					_msgout(LOG_WARNING,
429 					    "unable to register TCP6 service");
430 				else
431 					xcreated++;
432 			} else
433 				_msgout(LOG_WARNING,
434 				    "unable to create TCP6 service");
435 		} else
436 			_msgout(LOG_ERR, "unable to bind reserved TCP6 port");
437 		freenetconfigent(tcp6conf);
438 	}
439 
440 	if (xcreated == 0) {
441 		_msgout(LOG_ERR, "unable to create any services");
442 		exit(1);
443 	}
444 
445 	svc_run();
446 	_msgout(LOG_ERR, "svc_run returned");
447 	exit(1);
448 	/* NOTREACHED */
449 }
450 
451 void
452 sighandler(int sig)
453 {
454 
455 	/* SIGCHLD */
456 	while (wait3((int *)NULL, WNOHANG, (struct rusage *)NULL) > 0);
457 }
458 
459 void
460 usage(void)
461 {
462 
463 #ifdef LIBWRAP
464 #define	USAGESTR	"usage: %s [-d] [-l]\n"
465 #else
466 #define	USAGESTR	"usage: %s [-d]\n"
467 #endif
468 
469 	fprintf(stderr, USAGESTR, getprogname());
470 	exit(1);
471 
472 #undef USAGESTR
473 }
474 
475 /*
476  * _yp_invalid_map: check if given map name isn't legal.
477  * returns non-zero if invalid
478  *
479  * XXX: this probably should be in libc/yp/yplib.c
480  */
481 int
482 _yp_invalid_map(const char *map)
483 {
484 	if (map == NULL || *map == '\0')
485 		return 1;
486 
487 	if (strlen(map) > YPMAXMAP)
488 		return 1;
489 
490 	if (strchr(map, '/') != NULL)
491 		return 1;
492 
493 	return 0;
494 }
495