xref: /freebsd/libexec/ypxfr/ypxfr_main.c (revision 2008043f386721d58158e37e0d7e50df8095942d)
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 #include <errno.h>
37 #include <stdio.h>
38 #include <stdlib.h>
39 #include <string.h>
40 #include <syslog.h>
41 #include <unistd.h>
42 #include <sys/types.h>
43 #include <sys/param.h>
44 #include <sys/socket.h>
45 #include <netinet/in.h>
46 #include <arpa/inet.h>
47 #include <rpc/rpc.h>
48 #include <rpc/clnt.h>
49 #include <rpcsvc/yp.h>
50 #include <rpcsvc/ypclnt.h>
51 #include <rpcsvc/ypxfrd.h>
52 #include "ypxfr_extern.h"
53 
54 int debug = 1;
55 
56 char *progname = "ypxfr";
57 char *yp_dir = _PATH_YP;
58 int _rpcpmstart = 0;
59 static int ypxfr_use_yplib = 0; /* Assume the worst. */
60 static int ypxfr_clear = 1;
61 static int ypxfr_prognum = 0;
62 static struct sockaddr_in ypxfr_callback_addr;
63 static struct yppushresp_xfr ypxfr_resp;
64 static DB *dbp;
65 
66 static void
67 ypxfr_exit(ypxfrstat retval, char *temp)
68 {
69 	CLIENT *clnt;
70 	int sock = RPC_ANYSOCK;
71 	struct timeval timeout;
72 
73 	/* Clean up no matter what happened previously. */
74 	if (temp != NULL) {
75 		if (dbp != NULL)
76 			(void)(dbp->close)(dbp);
77 		if (unlink(temp) == -1) {
78 			yp_error("failed to unlink %s",strerror(errno));
79 		}
80 	}
81 
82 	if (ypxfr_prognum) {
83 		timeout.tv_sec = 20;
84 		timeout.tv_usec = 0;
85 
86 		if ((clnt = clntudp_create(&ypxfr_callback_addr, ypxfr_prognum,
87 					1, timeout, &sock)) == NULL) {
88 			yp_error("%s", clnt_spcreateerror("failed to "
89 			    "establish callback handle"));
90 			exit(1);
91 		}
92 
93 		ypxfr_resp.status = (yppush_status)retval;
94 
95 		if (yppushproc_xfrresp_1(&ypxfr_resp, clnt) == NULL) {
96 			yp_error("%s", clnt_sperror(clnt, "callback failed"));
97 			clnt_destroy(clnt);
98 			exit(1);
99 		}
100 		clnt_destroy(clnt);
101 	} else {
102 		yp_error("Exiting: %s", ypxfrerr_string(retval));
103 	}
104 
105 	exit(0);
106 }
107 
108 static void
109 usage(void)
110 {
111 	if (_rpcpmstart) {
112 		ypxfr_exit(YPXFR_BADARGS,NULL);
113 	} else {
114 		fprintf(stderr, "%s\n%s\n%s\n",
115 	"usage: ypxfr [-f] [-c] [-d target domain] [-h source host]",
116 	"             [-s source domain] [-p path]",
117 	"             [-C taskid program-number ipaddr port] mapname");
118 		exit(1);
119 	}
120 }
121 
122 int
123 ypxfr_foreach(int status, char *key, int keylen, char *val, int vallen,
124     char *data)
125 {
126 	DBT dbkey, dbval;
127 
128 	if (status != YP_TRUE)
129 		return (status);
130 
131 	/*
132 	 * XXX Do not attempt to write zero-length keys or
133 	 * data into a Berkeley DB hash database. It causes a
134 	 * strange failure mode where sequential searches get
135 	 * caught in an infinite loop.
136 	 */
137 	if (keylen) {
138 		dbkey.data = key;
139 		dbkey.size = keylen;
140 	} else {
141 		dbkey.data = "";
142 		dbkey.size = 1;
143 	}
144 	if (vallen) {
145 		dbval.data = val;
146 		dbval.size = vallen;
147 	} else {
148 		dbval.data = "";
149 		dbval.size = 1;
150 	}
151 
152 	if (yp_put_record(dbp, &dbkey, &dbval, 0) != YP_TRUE)
153 		return(yp_errno);
154 
155 	return (0);
156 }
157 
158 int
159 main(int argc, char *argv[])
160 {
161 	int ch;
162 	int ypxfr_force = 0;
163 	char *ypxfr_dest_domain = NULL;
164 	char *ypxfr_source_host = NULL;
165 	char *ypxfr_source_domain = NULL;
166 	char *ypxfr_local_domain = NULL;
167 	char *ypxfr_master = NULL;
168 	unsigned long ypxfr_order = -1, ypxfr_skew_check = -1;
169 	char *ypxfr_mapname = NULL;
170 	int ypxfr_args = 0;
171 	char ypxfr_temp_map[MAXPATHLEN + 2];
172 	char tempmap[MAXPATHLEN + 2];
173 	char buf[MAXPATHLEN + 2];
174 	DBT key, data;
175 	int remoteport;
176 	int interdom = 0;
177 	int secure = 0;
178 
179 	if (!isatty(fileno(stderr))) {
180 		openlog("ypxfr", LOG_PID, LOG_DAEMON);
181 		_rpcpmstart = 1;
182 	}
183 
184 	if (argc < 2)
185 		usage();
186 
187 	while ((ch = getopt(argc, argv, "fcd:h:s:p:C:")) != -1) {
188 		int my_optind;
189 		switch (ch) {
190 		case 'f':
191 			ypxfr_force++;
192 			ypxfr_args++;
193 			break;
194 		case 'c':
195 			ypxfr_clear = 0;
196 			ypxfr_args++;
197 			break;
198 		case 'd':
199 			ypxfr_dest_domain = optarg;
200 			ypxfr_args += 2;
201 			break;
202 		case 'h':
203 			ypxfr_source_host = optarg;
204 			ypxfr_args += 2;
205 			break;
206 		case 's':
207 			ypxfr_source_domain = optarg;
208 			ypxfr_args += 2;
209 			break;
210 		case 'p':
211 			yp_dir = optarg;
212 			ypxfr_args += 2;
213 			break;
214 		case 'C':
215 			/*
216 			 * Whoever decided that the -C flag should take
217 			 * four arguments is a twit.
218 			 */
219 			my_optind = optind - 1;
220 			if (argv[my_optind] == NULL || !strlen(argv[my_optind])) {
221 				yp_error("transaction ID not specified");
222 				usage();
223 			}
224 			ypxfr_resp.transid = atol(argv[my_optind]);
225 			my_optind++;
226 			if (argv[my_optind] == NULL || !strlen(argv[my_optind])) {
227 				yp_error("RPC program number not specified");
228 				usage();
229 			}
230 			ypxfr_prognum = atol(argv[my_optind]);
231 			my_optind++;
232 			if (argv[my_optind] == NULL || !strlen(argv[my_optind])) {
233 				yp_error("address not specified");
234 				usage();
235 			}
236 			if (!inet_aton(argv[my_optind], &ypxfr_callback_addr.sin_addr)) {
237 				yp_error("failed to convert '%s' to IP addr",
238 					argv[my_optind]);
239 				exit(1);
240 			}
241 			my_optind++;
242 			if (argv[my_optind] == NULL || !strlen(argv[my_optind])) {
243 				yp_error("port not specified");
244 				usage();
245 			}
246 			ypxfr_callback_addr.sin_port = htons((u_short)atoi(argv[my_optind]));
247 			ypxfr_args += 5;
248 			break;
249 		default:
250 			usage();
251 			break;
252 		}
253 	}
254 
255 	ypxfr_mapname = argv[ypxfr_args + 1];
256 
257 	if (ypxfr_mapname == NULL) {
258 		yp_error("no map name specified");
259 		usage();
260 	}
261 
262 	/* Always the case. */
263 	ypxfr_callback_addr.sin_family = AF_INET;
264 
265 	/* Determine if local NIS client facilities are turned on. */
266 	if (!yp_get_default_domain(&ypxfr_local_domain) &&
267 	    _yp_check(&ypxfr_local_domain))
268 		ypxfr_use_yplib = 1;
269 
270 	/*
271 	 * If no destination domain is specified, assume that the
272 	 * local default domain is to be used and try to obtain it.
273 	 * Fails if NIS client facilities are turned off.
274 	 */
275 	if (ypxfr_dest_domain == NULL) {
276 		if (ypxfr_use_yplib) {
277 			yp_get_default_domain(&ypxfr_dest_domain);
278 		} else {
279 			yp_error("no destination domain specified and \
280 the local domain name isn't set");
281 			ypxfr_exit(YPXFR_BADARGS,NULL);
282 		}
283 	}
284 
285 	/*
286 	 * If a source domain is not specified, assume it to
287 	 * be the same as the destination domain.
288 	 */
289 	if (ypxfr_source_domain == NULL) {
290 		ypxfr_source_domain = ypxfr_dest_domain;
291 	}
292 
293 	/*
294 	 * If the source host is not specified, assume it to be the
295 	 * master for the specified map. If local NIS client facilities
296 	 * are turned on, we can figure this out using yp_master().
297 	 * If not, we have to see if a local copy of the map exists
298 	 * and extract its YP_MASTER_NAME record. If _that_ fails,
299 	 * we are stuck and must ask the user for more information.
300 	 */
301 	if (ypxfr_source_host == NULL) {
302 		if (!ypxfr_use_yplib) {
303 		/*
304 		 * Double whammy: NIS isn't turned on and the user
305 		 * didn't specify a source host.
306 		 */
307 			char *dptr;
308 			key.data = "YP_MASTER_NAME";
309 			key.size = sizeof("YP_MASTER_NAME") - 1;
310 
311 			if (yp_get_record(ypxfr_dest_domain, ypxfr_mapname,
312 					 &key, &data, 1) != YP_TRUE) {
313 				yp_error("no source host specified");
314 				ypxfr_exit(YPXFR_BADARGS,NULL);
315 			}
316 			dptr = data.data;
317 			dptr[data.size] = '\0';
318 			ypxfr_master = ypxfr_source_host = strdup(dptr);
319 		}
320 	} else {
321 		if (ypxfr_use_yplib)
322 			ypxfr_use_yplib = 0;
323 	}
324 
325 	if (ypxfr_master == NULL) {
326 		if ((ypxfr_master = ypxfr_get_master(ypxfr_source_domain,
327 					    	 ypxfr_mapname,
328 					     	ypxfr_source_host,
329 					     	ypxfr_use_yplib)) == NULL) {
330 			yp_error("failed to find master of %s in domain %s: %s",
331 				  ypxfr_mapname, ypxfr_source_domain,
332 				  ypxfrerr_string((ypxfrstat)yp_errno));
333 			ypxfr_exit(YPXFR_MADDR,NULL);
334 		}
335 	}
336 
337 	/*
338 	 * If we got here and ypxfr_source_host is still undefined,
339 	 * it means we had to resort to using yp_master() to find the
340 	 * master server for the map. The source host and master should
341 	 * be identical.
342 	 */
343 	if (ypxfr_source_host == NULL)
344 		ypxfr_source_host = ypxfr_master;
345 
346 	/*
347 	 * Don't talk to ypservs on unprivileged ports.
348 	 */
349 	remoteport = getrpcport(ypxfr_source_host, YPPROG, YPVERS, IPPROTO_UDP);
350 	if (remoteport >= IPPORT_RESERVED) {
351 		yp_error("ypserv on %s not running on reserved port",
352 						ypxfr_source_host);
353 		ypxfr_exit(YPXFR_REFUSED, NULL);
354 	}
355 
356 	if ((ypxfr_order = ypxfr_get_order(ypxfr_source_domain,
357 					     ypxfr_mapname,
358 					     ypxfr_master, 0)) == 0) {
359 		yp_error("failed to get order number of %s: %s",
360 				ypxfr_mapname, yp_errno == YP_TRUE ?
361 				"map has order 0" :
362 				ypxfrerr_string((ypxfrstat)yp_errno));
363 		ypxfr_exit(YPXFR_YPERR,NULL);
364 	}
365 
366 	if (ypxfr_match(ypxfr_master, ypxfr_source_domain, ypxfr_mapname,
367 			"YP_INTERDOMAIN", sizeof("YP_INTERDOMAIN") - 1))
368 		interdom++;
369 
370 	if (ypxfr_match(ypxfr_master, ypxfr_source_domain, ypxfr_mapname,
371 			"YP_SECURE", sizeof("YP_SECURE") - 1))
372 		secure++;
373 
374 	key.data = "YP_LAST_MODIFIED";
375 	key.size = sizeof("YP_LAST_MODIFIED") - 1;
376 
377 	/* The order number is immaterial when the 'force' flag is set. */
378 
379 	if (!ypxfr_force) {
380 		int ignore = 0;
381 		if (yp_get_record(ypxfr_dest_domain,ypxfr_mapname,&key,&data,1) != YP_TRUE) {
382 			switch (yp_errno) {
383 			case YP_NOKEY:
384 				ypxfr_exit(YPXFR_FORCE,NULL);
385 				break;
386 			case YP_NOMAP:
387 				/*
388 				 * If the map doesn't exist, we're
389 				 * creating it. Ignore the error.
390 				 */
391 				ignore++;
392 				break;
393 			case YP_BADDB:
394 			default:
395 				ypxfr_exit(YPXFR_DBM,NULL);
396 				break;
397 			}
398 		}
399 		if (!ignore && ypxfr_order <= atoi(data.data))
400 			ypxfr_exit(YPXFR_AGE, NULL);
401 
402 	}
403 
404 	/* Construct a temporary map file name */
405 	snprintf(tempmap, sizeof(tempmap), "%s.%d",ypxfr_mapname, getpid());
406 	snprintf(ypxfr_temp_map, sizeof(ypxfr_temp_map), "%s/%s/%s", yp_dir,
407 		 ypxfr_dest_domain, tempmap);
408 
409 	if ((remoteport = getrpcport(ypxfr_source_host, YPXFRD_FREEBSD_PROG,
410 					YPXFRD_FREEBSD_VERS, IPPROTO_TCP))) {
411 
412 		/* Don't talk to rpc.ypxfrds on unprovileged ports. */
413 		if (remoteport >= IPPORT_RESERVED) {
414 			yp_error("rpc.ypxfrd on %s not using privileged port",
415 							ypxfr_source_host);
416 			ypxfr_exit(YPXFR_REFUSED, NULL);
417 		}
418 
419 		/* Try to send using ypxfrd. If it fails, use old method. */
420 		if (!ypxfrd_get_map(ypxfr_source_host, ypxfr_mapname,
421 					ypxfr_source_domain, ypxfr_temp_map))
422 			goto leave;
423 	}
424 
425 	/* Open the temporary map read/write. */
426 	if ((dbp = yp_open_db_rw(ypxfr_dest_domain, tempmap, 0)) == NULL) {
427 		yp_error("failed to open temporary map file");
428 		ypxfr_exit(YPXFR_DBM,NULL);
429 	}
430 
431 	/*
432 	 * Fill in the keys we already know, such as the order number,
433 	 * master name, input file name (we actually make up a bogus
434 	 * name for that) and output file name.
435 	 */
436 	snprintf(buf, sizeof(buf), "%lu", ypxfr_order);
437 	data.data = buf;
438 	data.size = strlen(buf);
439 
440 	if (yp_put_record(dbp, &key, &data, 0) != YP_TRUE) {
441 		yp_error("failed to write order number to database");
442 		ypxfr_exit(YPXFR_DBM,ypxfr_temp_map);
443 	}
444 
445 	key.data = "YP_MASTER_NAME";
446 	key.size = sizeof("YP_MASTER_NAME") - 1;
447 	data.data = ypxfr_master;
448 	data.size = strlen(ypxfr_master);
449 
450 	if (yp_put_record(dbp, &key, &data, 0) != YP_TRUE) {
451 		yp_error("failed to write master name to database");
452 		ypxfr_exit(YPXFR_DBM,ypxfr_temp_map);
453 	}
454 
455 	key.data = "YP_DOMAIN_NAME";
456 	key.size = sizeof("YP_DOMAIN_NAME") - 1;
457 	data.data = ypxfr_dest_domain;
458 	data.size = strlen(ypxfr_dest_domain);
459 
460 	if (yp_put_record(dbp, &key, &data, 0) != YP_TRUE) {
461 		yp_error("failed to write domain name to database");
462 		ypxfr_exit(YPXFR_DBM,ypxfr_temp_map);
463 	}
464 
465 	snprintf (buf, sizeof(buf), "%s:%s", ypxfr_source_host, ypxfr_mapname);
466 
467 	key.data = "YP_INPUT_NAME";
468 	key.size = sizeof("YP_INPUT_NAME") - 1;
469 	data.data = &buf;
470 	data.size = strlen(buf);
471 
472 	if (yp_put_record(dbp, &key, &data, 0) != YP_TRUE) {
473 		yp_error("failed to write input name to database");
474 		ypxfr_exit(YPXFR_DBM,ypxfr_temp_map);
475 
476 	}
477 
478 	snprintf(buf, sizeof(buf), "%s/%s/%s", yp_dir, ypxfr_dest_domain,
479 							ypxfr_mapname);
480 
481 	key.data = "YP_OUTPUT_NAME";
482 	key.size = sizeof("YP_OUTPUT_NAME") - 1;
483 	data.data = &buf;
484 	data.size = strlen(buf);
485 
486 	if (yp_put_record(dbp, &key, &data, 0) != YP_TRUE) {
487 		yp_error("failed to write output name to database");
488 		ypxfr_exit(YPXFR_DBM,ypxfr_temp_map);
489 	}
490 
491 	if (interdom) {
492 		key.data = "YP_INTERDOMAIN";
493 		key.size = sizeof("YP_INTERDOMAIN") - 1;
494 		data.data = "";
495 		data.size = 0;
496 
497 		if (yp_put_record(dbp, &key, &data, 0) != YP_TRUE) {
498 			yp_error("failed to add interdomain flag to database");
499 			ypxfr_exit(YPXFR_DBM,ypxfr_temp_map);
500 		}
501 	}
502 
503 	if (secure) {
504 		key.data = "YP_SECURE";
505 		key.size = sizeof("YP_SECURE") - 1;
506 		data.data = "";
507 		data.size = 0;
508 
509 		if (yp_put_record(dbp, &key, &data, 0) != YP_TRUE) {
510 			yp_error("failed to add secure flag to database");
511 			ypxfr_exit(YPXFR_DBM,ypxfr_temp_map);
512 		}
513 	}
514 
515 	/* Now suck over the contents of the map from the master. */
516 
517 	if (ypxfr_get_map(ypxfr_mapname,ypxfr_source_domain,
518 			  ypxfr_source_host, ypxfr_foreach)){
519 		yp_error("failed to retrieve map from source host");
520 		ypxfr_exit(YPXFR_YPERR,ypxfr_temp_map);
521 	}
522 
523 	(void)(dbp->close)(dbp);
524 	dbp = NULL; /* <- yes, it seems this is necessary. */
525 
526 leave:
527 
528 	snprintf(buf, sizeof(buf), "%s/%s/%s", yp_dir, ypxfr_dest_domain,
529 							ypxfr_mapname);
530 
531 	/* Peek at the order number again and check for skew. */
532 	if ((ypxfr_skew_check = ypxfr_get_order(ypxfr_source_domain,
533 					     ypxfr_mapname,
534 					     ypxfr_master, 0)) == 0) {
535 		yp_error("failed to get order number of %s: %s",
536 				ypxfr_mapname, yp_errno == YP_TRUE ?
537 				"map has order 0" :
538 				ypxfrerr_string((ypxfrstat)yp_errno));
539 		ypxfr_exit(YPXFR_YPERR,ypxfr_temp_map);
540 	}
541 
542 	if (ypxfr_order != ypxfr_skew_check)
543 		ypxfr_exit(YPXFR_SKEW,ypxfr_temp_map);
544 
545 	/*
546 	 * Send a YPPROC_CLEAR to the local ypserv.
547 	 */
548 	if (ypxfr_clear) {
549 		char in = 0;
550 		char *out = NULL;
551 		int stat;
552 		if ((stat = callrpc("localhost",YPPROG,YPVERS,YPPROC_CLEAR,
553 			(xdrproc_t)xdr_void, (void *)&in,
554 			(xdrproc_t)xdr_void, (void *)out)) != RPC_SUCCESS) {
555 			yp_error("failed to send 'clear' to local ypserv: %s",
556 				 clnt_sperrno((enum clnt_stat) stat));
557 			ypxfr_exit(YPXFR_CLEAR, ypxfr_temp_map);
558 		}
559 	}
560 
561 	/*
562 	 * Put the new map in place immediately. I'm not sure if the
563 	 * kernel does an unlink() and rename() atomically in the event
564 	 * that we move a new copy of a map over the top of an existing
565 	 * one, but there's less chance of a race condition happening
566 	 * than if we were to do the unlink() ourselves.
567 	 */
568 	if (rename(ypxfr_temp_map, buf) == -1) {
569 		yp_error("rename(%s,%s) failed: %s", ypxfr_temp_map, buf,
570 							strerror(errno));
571 		ypxfr_exit(YPXFR_FILE,NULL);
572 	}
573 
574 	ypxfr_exit(YPXFR_SUCC,NULL);
575 
576 	return(1);
577 }
578