xref: /freebsd/libexec/ypxfr/ypxfr_main.c (revision 7f3dea244c40159a41ab22da77a434d7c5b5e85a)
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 #ifndef lint
34 static const char rcsid[] =
35   "$FreeBSD$";
36 #endif /* not lint */
37 
38 #include <errno.h>
39 #include <stdio.h>
40 #include <stdlib.h>
41 #include <string.h>
42 #include <syslog.h>
43 #include <unistd.h>
44 #include <sys/types.h>
45 #include <sys/param.h>
46 #include <sys/socket.h>
47 #include <netinet/in.h>
48 #include <arpa/inet.h>
49 #include <rpc/rpc.h>
50 #include <rpc/clnt.h>
51 #include <rpcsvc/yp.h>
52 struct dom_binding {};
53 #include <rpcsvc/ypclnt.h>
54 #include <rpcsvc/ypxfrd.h>
55 #include "ypxfr_extern.h"
56 
57 char *progname = "ypxfr";
58 char *yp_dir = _PATH_YP;
59 int _rpcpmstart = 0;
60 int ypxfr_use_yplib = 0; /* Assume the worst. */
61 int ypxfr_clear = 1;
62 int ypxfr_prognum = 0;
63 struct sockaddr_in ypxfr_callback_addr;
64 struct yppushresp_xfr ypxfr_resp;
65 DB *dbp;
66 
67 static void ypxfr_exit(retval, temp)
68 	ypxfrstat retval;
69 	char *temp;
70 {
71 	CLIENT *clnt;
72 	int sock = RPC_ANYSOCK;
73 	struct timeval timeout;
74 
75 	/* Clean up no matter what happened previously. */
76 	if (temp != NULL) {
77 		if (dbp != NULL)
78 			(void)(dbp->close)(dbp);
79 		if (unlink(temp) == -1) {
80 			yp_error("failed to unlink %s",strerror(errno));
81 		}
82 	}
83 
84 	if (ypxfr_prognum) {
85 		timeout.tv_sec = 20;
86 		timeout.tv_usec = 0;
87 
88 		if ((clnt = clntudp_create(&ypxfr_callback_addr, ypxfr_prognum,
89 					1, timeout, &sock)) == NULL) {
90 			yp_error("%s", clnt_spcreateerror("failed to "
91 			    "establish callback handle"));
92 			exit(1);
93 		}
94 
95 		ypxfr_resp.status = retval;
96 
97 		if (yppushproc_xfrresp_1(&ypxfr_resp, clnt) == NULL) {
98 			yp_error("%s", clnt_sperror(clnt, "callback failed"));
99 			clnt_destroy(clnt);
100 			exit(1);
101 		}
102 		clnt_destroy(clnt);
103 	} else {
104 		yp_error("Exiting: %s", ypxfrerr_string(retval));
105 	}
106 
107 	exit(0);
108 }
109 
110 static void usage()
111 {
112 	if (_rpcpmstart) {
113 		ypxfr_exit(YPXFR_BADARGS,NULL);
114 	} else {
115 		fprintf(stderr, "%s\n%s\n%s\n",
116 	"usage: ypxfr [-f] [-c] [-d target domain] [-h source host]",
117 	"             [-s source domain] [-p path]",
118 	"             [-C taskid program-number ipaddr port] mapname");
119 		exit(1);
120 	}
121 }
122 
123 int ypxfr_foreach(status, key, keylen, val, vallen, data)
124 	int status;
125 	char *key;
126 	int keylen;
127 	char *val;
128 	int vallen;
129 	char *data;
130 {
131 	DBT dbkey, dbval;
132 
133 	if (status != YP_TRUE)
134 		return (status);
135 
136 	/*
137 	 * XXX Do not attempt to write zero-length keys or
138 	 * data into a Berkeley DB hash database. It causes a
139 	 * strange failure mode where sequential searches get
140 	 * caught in an infinite loop.
141 	 */
142 	if (keylen) {
143 		dbkey.data = key;
144 		dbkey.size = keylen;
145 	} else {
146 		dbkey.data = "";
147 		dbkey.size = 1;
148 	}
149 	if (vallen) {
150 		dbval.data = val;
151 		dbval.size = vallen;
152 	} else {
153 		dbval.data = "";
154 		dbval.size = 1;
155 	}
156 
157 	if (yp_put_record(dbp, &dbkey, &dbval, 0) != YP_TRUE)
158 		return(yp_errno);
159 
160 	return (0);
161 }
162 
163 int
164 main(argc,argv)
165 	int argc;
166 	char *argv[];
167 {
168 	int ch;
169 	int ypxfr_force = 0;
170 	char *ypxfr_dest_domain = NULL;
171 	char *ypxfr_source_host = NULL;
172 	char *ypxfr_source_domain = NULL;
173 	char *ypxfr_local_domain = NULL;
174 	char *ypxfr_master = NULL;
175 	unsigned long ypxfr_order = -1, ypxfr_skew_check = -1;
176 	char *ypxfr_mapname = NULL;
177 	int ypxfr_args = 0;
178 	char ypxfr_temp_map[MAXPATHLEN + 2];
179 	char tempmap[MAXPATHLEN + 2];
180 	char buf[MAXPATHLEN + 2];
181 	DBT key, data;
182 	int remoteport;
183 	int interdom = 0;
184 	int secure = 0;
185 
186 	debug = 1;
187 
188 	if (!isatty(fileno(stderr))) {
189 		openlog("ypxfr", LOG_PID, LOG_DAEMON);
190 		_rpcpmstart = 1;
191 	}
192 
193 	if (argc < 2)
194 		usage();
195 
196 	while ((ch = getopt(argc, argv, "fcd:h:s:p:C:")) != -1) {
197 		int my_optind;
198 		switch(ch) {
199 		case 'f':
200 			ypxfr_force++;
201 			ypxfr_args++;
202 			break;
203 		case 'c':
204 			ypxfr_clear = 0;
205 			ypxfr_args++;
206 			break;
207 		case 'd':
208 			ypxfr_dest_domain = optarg;
209 			ypxfr_args += 2;
210 			break;
211 		case 'h':
212 			ypxfr_source_host = optarg;
213 			ypxfr_args += 2;
214 			break;
215 		case 's':
216 			ypxfr_source_domain = optarg;
217 			ypxfr_args += 2;
218 			break;
219 		case 'p':
220 			yp_dir = optarg;
221 			ypxfr_args += 2;
222 			break;
223 		case 'C':
224 			/*
225 			 * Whoever decided that the -C flag should take
226 			 * four arguments is a twit.
227 			 */
228 			my_optind = optind - 1;
229 			if (argv[my_optind] == NULL || !strlen(argv[my_optind])) {
230 				yp_error("transaction ID not specified");
231 				usage();
232 			}
233 			ypxfr_resp.transid = atol(argv[my_optind]);
234 			my_optind++;
235 			if (argv[my_optind] == NULL || !strlen(argv[my_optind])) {
236 				yp_error("RPC program number not specified");
237 				usage();
238 			}
239 			ypxfr_prognum = atol(argv[my_optind]);
240 			my_optind++;
241 			if (argv[my_optind] == NULL || !strlen(argv[my_optind])) {
242 				yp_error("address not specified");
243 				usage();
244 			}
245 			if (!inet_aton(argv[my_optind], &ypxfr_callback_addr.sin_addr)) {
246 				yp_error("failed to convert '%s' to IP addr",
247 					argv[my_optind]);
248 				exit(1);
249 			}
250 			my_optind++;
251 			if (argv[my_optind] == NULL || !strlen(argv[my_optind])) {
252 				yp_error("port not specified");
253 				usage();
254 			}
255 			ypxfr_callback_addr.sin_port = htons((u_short)atoi(argv[my_optind]));
256 			ypxfr_args += 5;
257 			break;
258 		default:
259 			usage();
260 			break;
261 		}
262 	}
263 
264 	ypxfr_mapname = argv[ypxfr_args + 1];
265 
266 	if (ypxfr_mapname == NULL) {
267 		yp_error("no map name specified");
268 		usage();
269 	}
270 
271 	/* Always the case. */
272 	ypxfr_callback_addr.sin_family = AF_INET;
273 
274 	/* Determine if local NIS client facilities are turned on. */
275 	if (!yp_get_default_domain(&ypxfr_local_domain) &&
276 	    _yp_check(&ypxfr_local_domain))
277 		ypxfr_use_yplib = 1;
278 
279 	/*
280 	 * If no destination domain is specified, assume that the
281 	 * local default domain is to be used and try to obtain it.
282 	 * Fails if NIS client facilities are turned off.
283 	 */
284 	if (ypxfr_dest_domain == NULL) {
285 		if (ypxfr_use_yplib) {
286 			yp_get_default_domain(&ypxfr_dest_domain);
287 		} else {
288 			yp_error("no destination domain specified and \
289 the local domain name isn't set");
290 			ypxfr_exit(YPXFR_BADARGS,NULL);
291 		}
292 	}
293 
294 	/*
295 	 * If a source domain is not specified, assume it to
296 	 * be the same as the destination domain.
297 	 */
298 	if (ypxfr_source_domain == NULL) {
299 		ypxfr_source_domain = ypxfr_dest_domain;
300 	}
301 
302 	/*
303 	 * If the source host is not specified, assume it to be the
304 	 * master for the specified map. If local NIS client facilities
305 	 * are turned on, we can figure this out using yp_master().
306 	 * If not, we have to see if a local copy of the map exists
307 	 * and extract its YP_MASTER_NAME record. If _that_ fails,
308 	 * we are stuck and must ask the user for more information.
309 	 */
310 	if (ypxfr_source_host == NULL) {
311 		if (!ypxfr_use_yplib) {
312 		/*
313 		 * Double whammy: NIS isn't turned on and the user
314 		 * didn't specify a source host.
315 		 */
316 			char *dptr;
317 			key.data = "YP_MASTER_NAME";
318 			key.size = sizeof("YP_MASTER_NAME") - 1;
319 
320 			if (yp_get_record(ypxfr_dest_domain, ypxfr_mapname,
321 					 &key, &data, 1) != YP_TRUE) {
322 				yp_error("no source host specified");
323 				ypxfr_exit(YPXFR_BADARGS,NULL);
324 			}
325 			dptr = data.data;
326 			dptr[data.size] = '\0';
327 			ypxfr_master = ypxfr_source_host = strdup(dptr);
328 		}
329 	} else {
330 		if (ypxfr_use_yplib)
331 			ypxfr_use_yplib = 0;
332 	}
333 
334 	if (ypxfr_master == NULL) {
335 		if ((ypxfr_master = ypxfr_get_master(ypxfr_source_domain,
336 					    	 ypxfr_mapname,
337 					     	ypxfr_source_host,
338 					     	ypxfr_use_yplib)) == NULL) {
339 			yp_error("failed to find master of %s in domain %s: %s",
340 				  ypxfr_mapname, ypxfr_source_domain,
341 				  ypxfrerr_string(yp_errno));
342 			ypxfr_exit(YPXFR_MADDR,NULL);
343 		}
344 	}
345 
346 	/*
347 	 * If we got here and ypxfr_source_host is still undefined,
348 	 * it means we had to resort to using yp_master() to find the
349 	 * master server for the map. The source host and master should
350 	 * be identical.
351 	 */
352 	if (ypxfr_source_host == NULL)
353 		ypxfr_source_host = ypxfr_master;
354 
355 	/*
356 	 * Don't talk to ypservs on unprivileged ports.
357 	 */
358 	remoteport = getrpcport(ypxfr_source_host, YPPROG, YPVERS, IPPROTO_UDP);
359 	if (remoteport >= IPPORT_RESERVED) {
360 		yp_error("ypserv on %s not running on reserved port",
361 						ypxfr_source_host);
362 		ypxfr_exit(YPXFR_REFUSED, NULL);
363 	}
364 
365 	if ((ypxfr_order = ypxfr_get_order(ypxfr_source_domain,
366 					     ypxfr_mapname,
367 					     ypxfr_master, 0)) == 0) {
368 		yp_error("failed to get order number of %s: %s",
369 				ypxfr_mapname, yp_errno == YPXFR_SUCC ?
370 				"map has order 0" : ypxfrerr_string(yp_errno));
371 		ypxfr_exit(YPXFR_YPERR,NULL);
372 	}
373 
374 	if (ypxfr_match(ypxfr_master, ypxfr_source_domain, ypxfr_mapname,
375 			"YP_INTERDOMAIN", sizeof("YP_INTERDOMAIN") - 1))
376 		interdom++;
377 
378 	if (ypxfr_match(ypxfr_master, ypxfr_source_domain, ypxfr_mapname,
379 			"YP_SECURE", sizeof("YP_SECURE") - 1))
380 		secure++;
381 
382 	key.data = "YP_LAST_MODIFIED";
383 	key.size = sizeof("YP_LAST_MODIFIED") - 1;
384 
385 	/* The order number is immaterial when the 'force' flag is set. */
386 
387 	if (!ypxfr_force) {
388 		int ignore = 0;
389 		if (yp_get_record(ypxfr_dest_domain,ypxfr_mapname,&key,&data,1) != YP_TRUE) {
390 			switch(yp_errno) {
391 			case YP_NOKEY:
392 				ypxfr_exit(YPXFR_FORCE,NULL);
393 				break;
394 			case YP_NOMAP:
395 				/*
396 				 * If the map doesn't exist, we're
397 				 * creating it. Ignore the error.
398 				 */
399 				ignore++;
400 				break;
401 			case YP_BADDB:
402 			default:
403 				ypxfr_exit(YPXFR_DBM,NULL);
404 				break;
405 			}
406 		}
407 		if (!ignore && ypxfr_order <= atoi(data.data))
408 			ypxfr_exit(YPXFR_AGE, NULL);
409 
410 	}
411 
412 	/* Construct a temporary map file name */
413 	snprintf(tempmap, sizeof(tempmap), "%s.%d",ypxfr_mapname, getpid());
414 	snprintf(ypxfr_temp_map, sizeof(ypxfr_temp_map), "%s/%s/%s", yp_dir,
415 		 ypxfr_dest_domain, tempmap);
416 
417 	if ((remoteport = getrpcport(ypxfr_source_host, YPXFRD_FREEBSD_PROG,
418 					YPXFRD_FREEBSD_VERS, IPPROTO_TCP))) {
419 
420 		/* Don't talk to rpc.ypxfrds on unprovileged ports. */
421 		if (remoteport >= IPPORT_RESERVED) {
422 			yp_error("rpc.ypxfrd on %s not using privileged port",
423 							ypxfr_source_host);
424 			ypxfr_exit(YPXFR_REFUSED, NULL);
425 		}
426 
427 		/* Try to send using ypxfrd. If it fails, use old method. */
428 		if (!ypxfrd_get_map(ypxfr_source_host, ypxfr_mapname,
429 					ypxfr_source_domain, ypxfr_temp_map))
430 			goto leave;
431 	}
432 
433 	/* Open the temporary map read/write. */
434 	if ((dbp = yp_open_db_rw(ypxfr_dest_domain, tempmap, 0)) == NULL) {
435 		yp_error("failed to open temporary map file");
436 		ypxfr_exit(YPXFR_DBM,NULL);
437 	}
438 
439 	/*
440 	 * Fill in the keys we already know, such as the order number,
441 	 * master name, input file name (we actually make up a bogus
442 	 * name for that) and output file name.
443 	 */
444 	snprintf(buf, sizeof(buf), "%lu", ypxfr_order);
445 	data.data = buf;
446 	data.size = strlen(buf);
447 
448 	if (yp_put_record(dbp, &key, &data, 0) != YP_TRUE) {
449 		yp_error("failed to write order number to database");
450 		ypxfr_exit(YPXFR_DBM,&ypxfr_temp_map);
451 	}
452 
453 	key.data = "YP_MASTER_NAME";
454 	key.size = sizeof("YP_MASTER_NAME") - 1;
455 	data.data = ypxfr_master;
456 	data.size = strlen(ypxfr_master);
457 
458 	if (yp_put_record(dbp, &key, &data, 0) != YP_TRUE) {
459 		yp_error("failed to write master name to database");
460 		ypxfr_exit(YPXFR_DBM,&ypxfr_temp_map);
461 	}
462 
463 	key.data = "YP_DOMAIN_NAME";
464 	key.size = sizeof("YP_DOMAIN_NAME") - 1;
465 	data.data = ypxfr_dest_domain;
466 	data.size = strlen(ypxfr_dest_domain);
467 
468 	if (yp_put_record(dbp, &key, &data, 0) != YP_TRUE) {
469 		yp_error("failed to write domain name to database");
470 		ypxfr_exit(YPXFR_DBM,&ypxfr_temp_map);
471 	}
472 
473 	snprintf (buf, sizeof(buf), "%s:%s", ypxfr_source_host, ypxfr_mapname);
474 
475 	key.data = "YP_INPUT_NAME";
476 	key.size = sizeof("YP_INPUT_NAME") - 1;
477 	data.data = &buf;
478 	data.size = strlen(buf);
479 
480 	if (yp_put_record(dbp, &key, &data, 0) != YP_TRUE) {
481 		yp_error("failed to write input name to database");
482 		ypxfr_exit(YPXFR_DBM,&ypxfr_temp_map);
483 
484 	}
485 
486 	snprintf(buf, sizeof(buf), "%s/%s/%s", yp_dir, ypxfr_dest_domain,
487 							ypxfr_mapname);
488 
489 	key.data = "YP_OUTPUT_NAME";
490 	key.size = sizeof("YP_OUTPUT_NAME") - 1;
491 	data.data = &buf;
492 	data.size = strlen(buf);
493 
494 	if (yp_put_record(dbp, &key, &data, 0) != YP_TRUE) {
495 		yp_error("failed to write output name to database");
496 		ypxfr_exit(YPXFR_DBM,&ypxfr_temp_map);
497 	}
498 
499 	if (interdom) {
500 		key.data = "YP_INTERDOMAIN";
501 		key.size = sizeof("YP_INTERDOMAIN") - 1;
502 		data.data = "";
503 		data.size = 0;
504 
505 		if (yp_put_record(dbp, &key, &data, 0) != YP_TRUE) {
506 			yp_error("failed to add interdomain flag to database");
507 			ypxfr_exit(YPXFR_DBM,&ypxfr_temp_map);
508 		}
509 	}
510 
511 	if (secure) {
512 		key.data = "YP_SECURE";
513 		key.size = sizeof("YP_SECURE") - 1;
514 		data.data = "";
515 		data.size = 0;
516 
517 		if (yp_put_record(dbp, &key, &data, 0) != YP_TRUE) {
518 			yp_error("failed to add secure flag to database");
519 			ypxfr_exit(YPXFR_DBM,&ypxfr_temp_map);
520 		}
521 	}
522 
523 	/* Now suck over the contents of the map from the master. */
524 
525 	if (ypxfr_get_map(ypxfr_mapname,ypxfr_source_domain,
526 			  ypxfr_source_host, ypxfr_foreach)){
527 		yp_error("failed to retrieve map from source host");
528 		ypxfr_exit(YPXFR_YPERR,&ypxfr_temp_map);
529 	}
530 
531 	(void)(dbp->close)(dbp);
532 	dbp = NULL; /* <- yes, it seems this is necessary. */
533 
534 leave:
535 
536 	snprintf(buf, sizeof(buf), "%s/%s/%s", yp_dir, ypxfr_dest_domain,
537 							ypxfr_mapname);
538 
539 	/* Peek at the order number again and check for skew. */
540 	if ((ypxfr_skew_check = ypxfr_get_order(ypxfr_source_domain,
541 					     ypxfr_mapname,
542 					     ypxfr_master, 0)) == 0) {
543 		yp_error("failed to get order number of %s: %s",
544 				ypxfr_mapname, yp_errno == YPXFR_SUCC ?
545 				"map has order 0" : ypxfrerr_string(yp_errno));
546 		ypxfr_exit(YPXFR_YPERR,&ypxfr_temp_map);
547 	}
548 
549 	if (ypxfr_order != ypxfr_skew_check)
550 		ypxfr_exit(YPXFR_SKEW,&ypxfr_temp_map);
551 
552 	/*
553 	 * Send a YPPROC_CLEAR to the local ypserv.
554 	 */
555 	if (ypxfr_clear) {
556 		char in = 0;
557 		char *out = NULL;
558 		int stat;
559 		if ((stat = callrpc("localhost",YPPROG,YPVERS,YPPROC_CLEAR,
560 			xdr_void, (void *)&in,
561 			xdr_void, (void *)out)) != RPC_SUCCESS) {
562 			yp_error("failed to send 'clear' to local ypserv: %s",
563 				 clnt_sperrno((enum clnt_stat) stat));
564 			ypxfr_exit(YPXFR_CLEAR, &ypxfr_temp_map);
565 		}
566 	}
567 
568 	/*
569 	 * Put the new map in place immediately. I'm not sure if the
570 	 * kernel does an unlink() and rename() atomically in the event
571 	 * that we move a new copy of a map over the top of an existing
572 	 * one, but there's less chance of a race condition happening
573 	 * than if we were to do the unlink() ourselves.
574 	 */
575 	if (rename(ypxfr_temp_map, buf) == -1) {
576 		yp_error("rename(%s,%s) failed: %s", ypxfr_temp_map, buf,
577 							strerror(errno));
578 		ypxfr_exit(YPXFR_FILE,NULL);
579 	}
580 
581 	ypxfr_exit(YPXFR_SUCC,NULL);
582 
583 	return(1);
584 }
585