xref: /freebsd/usr.sbin/ypldap/yp.c (revision 0b3105a37d7adcadcb720112fed4dc4e8040be99) 
1 /*	$OpenBSD: yp.c,v 1.14 2015/02/11 01:26:00 pelikan Exp $ */
2 /*	$FreeBSD$ */
3 /*
4  * Copyright (c) 2008 Pierre-Yves Ritschard <pyr@openbsd.org>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 #include <sys/types.h>
20 #include <sys/param.h>
21 #include <sys/queue.h>
22 #include <sys/socket.h>
23 #include <sys/select.h>
24 #include <sys/tree.h>
25 
26 #include <netinet/in.h>
27 #include <arpa/inet.h>
28 
29 #include <errno.h>
30 #include <event.h>
31 #include <fcntl.h>
32 #include <unistd.h>
33 #include <pwd.h>
34 #include <stdio.h>
35 #include <stdlib.h>
36 #include <string.h>
37 #include <limits.h>
38 
39 #include <rpc/rpc.h>
40 #include <rpc/xdr.h>
41 #include <rpc/pmap_clnt.h>
42 #include <rpc/pmap_prot.h>
43 #include <rpc/pmap_rmt.h>
44 #include <rpcsvc/yp.h>
45 #include <rpcsvc/ypclnt.h>
46 
47 #include "ypldap.h"
48 
49 void	yp_dispatch(struct svc_req *, SVCXPRT *);
50 void	yp_disable_events(void);
51 void	yp_fd_event(int, short, void *);
52 int	yp_check(struct svc_req *);
53 int	yp_valid_domain(char *, struct ypresp_val *);
54 void	yp_make_val(struct ypresp_val *, char *, int);
55 void	yp_make_keyval(struct ypresp_key_val *, char *, char *);
56 
57 static struct env	*env;
58 
59 struct yp_event {
60 	TAILQ_ENTRY(yp_event)	 ye_entry;
61 	struct event		 ye_event;
62 };
63 
64 struct yp_data {
65 	SVCXPRT			*yp_trans_udp;
66 	SVCXPRT			*yp_trans_tcp;
67 	TAILQ_HEAD(, yp_event)	 yd_events;
68 };
69 
70 void
71 yp_disable_events(void)
72 {
73 	struct yp_event	*ye;
74 
75 	while ((ye = TAILQ_FIRST(&env->sc_yp->yd_events)) != NULL) {
76 		TAILQ_REMOVE(&env->sc_yp->yd_events, ye, ye_entry);
77 		event_del(&ye->ye_event);
78 		free(ye);
79 	}
80 }
81 
82 void
83 yp_enable_events(void)
84 {
85 	int i;
86 	struct yp_event	*ye;
87 
88 	for (i = 0; i < getdtablesize(); i++) {
89 		if ((ye = calloc(1, sizeof(*ye))) == NULL)
90 			fatal(NULL);
91 		event_set(&ye->ye_event, i, EV_READ, yp_fd_event, NULL);
92 		event_add(&ye->ye_event, NULL);
93 		TAILQ_INSERT_TAIL(&env->sc_yp->yd_events, ye, ye_entry);
94 	}
95 }
96 
97 void
98 yp_fd_event(int fd, short event, void *p)
99 {
100 	svc_getreq_common(fd);
101 	yp_disable_events();
102 	yp_enable_events();
103 }
104 
105 void
106 yp_init(struct env *x_env)
107 {
108 	struct yp_data	*yp;
109 
110 	if ((yp = calloc(1, sizeof(*yp))) == NULL)
111 		fatal(NULL);
112 	TAILQ_INIT(&yp->yd_events);
113 
114 	env = x_env;
115 	env->sc_yp = yp;
116 
117 	(void)pmap_unset(YPPROG, YPVERS);
118 
119 	if ((yp->yp_trans_udp = svcudp_create(RPC_ANYSOCK)) == NULL)
120 		fatal("cannot create udp service");
121 	if ((yp->yp_trans_tcp = svctcp_create(RPC_ANYSOCK, 0, 0)) == NULL)
122 		fatal("cannot create tcp service");
123 
124 	if (!svc_register(yp->yp_trans_udp, YPPROG, YPVERS,
125 	    yp_dispatch, IPPROTO_UDP)) {
126 		fatal("unable to register (YPPROG, YPVERS, udp)");
127 	}
128 	if (!svc_register(yp->yp_trans_tcp, YPPROG, YPVERS,
129 	    yp_dispatch, IPPROTO_TCP)) {
130 		fatal("unable to register (YPPROG, YPVERS, tcp)");
131 	}
132 }
133 
134 /*
135  * lots of inspiration from ypserv by Mats O Jansson
136  */
137 void
138 yp_dispatch(struct svc_req *req, SVCXPRT *trans)
139 {
140 	xdrproc_t		 xdr_argument;
141 	xdrproc_t		 xdr_result;
142 	char			*result;
143 	char			*(*cb)(char *, struct svc_req *);
144         union {
145 		domainname	 ypproc_domain_2_arg;
146 		domainname	 ypproc_domain_nonack_2_arg;
147 		ypreq_key	 ypproc_match_2_arg;
148 		ypreq_nokey	 ypproc_first_2_arg;
149 		ypreq_key	 ypproc_next_2_arg;
150 		ypreq_xfr	 ypproc_xfr_2_arg;
151 		ypreq_nokey	 ypproc_all_2_arg;
152 		ypreq_nokey	 ypproc_master_2_arg;
153 		ypreq_nokey	 ypproc_order_2_arg;
154 		domainname	 ypproc_maplist_2_arg;
155 	} argument;
156 
157 	xdr_argument = (xdrproc_t) xdr_void;
158 	xdr_result = (xdrproc_t) xdr_void;
159 	cb = NULL;
160 	switch (req->rq_proc) {
161 	case YPPROC_NULL:
162 		xdr_argument = (xdrproc_t) xdr_void;
163 		xdr_result = (xdrproc_t) xdr_void;
164 		if (yp_check(req) == -1)
165 			return;
166 		result = NULL;
167 		if (!svc_sendreply(trans, (xdrproc_t) xdr_void,
168 		    (void *)&result))
169 			svcerr_systemerr(trans);
170 		return;
171 	case YPPROC_DOMAIN:
172 		xdr_argument = (xdrproc_t) xdr_domainname;
173 		xdr_result = (xdrproc_t) xdr_bool;
174 		if (yp_check(req) == -1)
175 			return;
176 		cb = (void *)ypproc_domain_2_svc;
177 		break;
178 	case YPPROC_DOMAIN_NONACK:
179 		xdr_argument = (xdrproc_t) xdr_domainname;
180 		xdr_result = (xdrproc_t) xdr_bool;
181 		if (yp_check(req) == -1)
182 			return;
183 		cb = (void *)ypproc_domain_nonack_2_svc;
184 		break;
185 	case YPPROC_MATCH:
186 		xdr_argument = (xdrproc_t) xdr_ypreq_key;
187 		xdr_result = (xdrproc_t) xdr_ypresp_val;
188 		if (yp_check(req) == -1)
189 			return;
190 		cb = (void *)ypproc_match_2_svc;
191 		break;
192 	case YPPROC_FIRST:
193 		xdr_argument = (xdrproc_t) xdr_ypreq_nokey;
194 		xdr_result = (xdrproc_t) xdr_ypresp_key_val;
195 		if (yp_check(req) == -1)
196 			return;
197 		cb = (void *)ypproc_first_2_svc;
198 		break;
199 	case YPPROC_NEXT:
200 		xdr_argument = (xdrproc_t) xdr_ypreq_key;
201 		xdr_result = (xdrproc_t) xdr_ypresp_key_val;
202 		if (yp_check(req) == -1)
203 			return;
204 		cb = (void *)ypproc_next_2_svc;
205 		break;
206 	case YPPROC_XFR:
207 		if (yp_check(req) == -1)
208 			return;
209 		svcerr_noproc(trans);
210 		return;
211 	case YPPROC_CLEAR:
212 		log_debug("ypproc_clear");
213 		if (yp_check(req) == -1)
214 			return;
215 		svcerr_noproc(trans);
216 		return;
217 	case YPPROC_ALL:
218 		log_debug("ypproc_all");
219 		if (yp_check(req) == -1)
220 			return;
221 		cb = (void *)ypproc_all_2_svc;
222 		break;
223 	case YPPROC_MASTER:
224 		log_debug("ypproc_master");
225 		if (yp_check(req) == -1)
226 			return;
227 		cb = (void *)ypproc_master_2_svc;
228 		break;
229 	case YPPROC_ORDER:
230 		log_debug("ypproc_order");
231 		if (yp_check(req) == -1)
232 			return;
233 		svcerr_noproc(trans);
234 		return;
235 	case YPPROC_MAPLIST:
236 		log_debug("ypproc_maplist");
237 		if (yp_check(req) == -1)
238 			return;
239 		cb = (void *)ypproc_maplist_2_svc;
240 		break;
241 	default:
242 		svcerr_noproc(trans);
243 		return;
244 	}
245 	(void)memset(&argument, 0, sizeof(argument));
246 
247 	if (!svc_getargs(trans, xdr_argument, (caddr_t)&argument)) {
248 		svcerr_decode(trans);
249 		return;
250 	}
251 	result = (*cb)((char *)&argument, req);
252 	if (result != NULL && !svc_sendreply(trans, xdr_result, result))
253 		svcerr_systemerr(trans);
254 	if (!svc_freeargs(trans, xdr_argument, (caddr_t)&argument)) {
255 		/*
256 		 * ypserv does it too.
257 		 */
258 		fatal("unable to free arguments");
259 	}
260 }
261 
262 int
263 yp_check(struct svc_req *req)
264 {
265 	struct sockaddr_in	*caller;
266 
267 	caller = svc_getcaller(req->rq_xprt);
268 	/*
269 	 * We might want to know who we allow here.
270 	 */
271 	return (0);
272 }
273 
274 int
275 yp_valid_domain(char *domain, struct ypresp_val *res)
276 {
277 	if (domain == NULL) {
278 		log_debug("NULL domain !");
279 		return (-1);
280 	}
281 	if (strcmp(domain, env->sc_domainname) != 0) {
282 		res->stat = YP_NODOM;
283 		return (-1);
284 	}
285 	return (0);
286 }
287 
288 bool_t *
289 ypproc_domain_2_svc(domainname *arg, struct svc_req *req)
290 {
291 	static bool_t	res;
292 
293 	res = (bool_t)1;
294 	if (strcmp(*arg, env->sc_domainname) != 0)
295 		res = (bool_t)0;
296 	return (&res);
297 }
298 
299 bool_t *
300 ypproc_domain_nonack_2_svc(domainname *arg, struct svc_req *req)
301 {
302 	static bool_t	res;
303 
304 	if (strcmp(*arg, env->sc_domainname) != 0)
305 		return NULL;
306 	res = (bool_t)1;
307 	return (&res);
308 }
309 
310 ypresp_val *
311 ypproc_match_2_svc(ypreq_key *arg, struct svc_req *req)
312 {
313 	struct userent		 ukey;
314 	struct userent		*ue;
315 	struct groupent		 gkey;
316 	struct groupent		*ge;
317 	static struct ypresp_val res;
318 	const char		*estr;
319 	char			*bp, *cp;
320 	char			 key[YPMAXRECORD+1];
321 
322 	log_debug("matching '%.*s' in map %s", arg->key.keydat_len,
323 	   arg->key.keydat_val, arg->map);
324 
325 	if (yp_valid_domain(arg->domain, (struct ypresp_val *)&res) == -1)
326 		return (&res);
327 
328 	if (env->sc_user_names == NULL) {
329 		/*
330 		 * tree not ready.
331 		 */
332 		return (NULL);
333 	}
334 
335 	if (arg->key.keydat_len > YPMAXRECORD) {
336 		log_debug("argument too long");
337 		return (NULL);
338 	}
339 	bzero(key, sizeof(key));
340 	(void)strncpy(key, arg->key.keydat_val, arg->key.keydat_len);
341 
342 	if (strcmp(arg->map, "passwd.byname") == 0 ||
343 	    strcmp(arg->map, "master.passwd.byname") == 0) {
344 		ukey.ue_line = key;
345 		if ((ue = RB_FIND(user_name_tree, env->sc_user_names,
346 		    &ukey)) == NULL) {
347 			res.stat = YP_NOKEY;
348 			return (&res);
349 		}
350 
351 		yp_make_val(&res, ue->ue_line, 1);
352 		return (&res);
353 	} else if (strcmp(arg->map, "passwd.byuid") == 0 ||
354 		   strcmp(arg->map, "master.passwd.byuid") == 0) {
355 		ukey.ue_uid = strtonum(key, 0, UID_MAX, &estr);
356 		if (estr) {
357 			res.stat = YP_BADARGS;
358 			return (&res);
359 		}
360 
361 		if ((ue = RB_FIND(user_uid_tree, &env->sc_user_uids,
362 		    &ukey)) == NULL) {
363 			res.stat = YP_NOKEY;
364 			return (&res);
365 		}
366 
367 		yp_make_val(&res, ue->ue_line, 1);
368 		return (&res);
369 	} else if (strcmp(arg->map, "group.bygid") == 0) {
370 		gkey.ge_gid = strtonum(key, 0, GID_MAX, &estr);
371 		if (estr) {
372 			res.stat = YP_BADARGS;
373 			return (&res);
374 		}
375 		if ((ge = RB_FIND(group_gid_tree, &env->sc_group_gids,
376 		    &gkey)) == NULL) {
377 			res.stat = YP_NOKEY;
378 			return (&res);
379 		}
380 
381 		yp_make_val(&res, ge->ge_line, 1);
382 		return (&res);
383 	} else if (strcmp(arg->map, "group.byname") == 0) {
384 		gkey.ge_line = key;
385 		if ((ge = RB_FIND(group_name_tree, env->sc_group_names,
386 		    &gkey)) == NULL) {
387 			res.stat = YP_NOKEY;
388 			return (&res);
389 		}
390 
391 		yp_make_val(&res, ge->ge_line, 1);
392 		return (&res);
393 	} else if (strcmp(arg->map, "netid.byname") == 0) {
394 		bp = cp = key;
395 
396 		if (strncmp(bp, "unix.", strlen("unix.")) != 0) {
397 			res.stat = YP_BADARGS;
398 			return (&res);
399 		}
400 
401 		bp += strlen("unix.");
402 
403 		if (*bp == '\0') {
404 			res.stat = YP_BADARGS;
405 			return (&res);
406 		}
407 
408 		if (!(cp = strsep(&bp, "@"))) {
409 			res.stat = YP_BADARGS;
410 			return (&res);
411 		}
412 
413 		if (strcmp(bp, arg->domain) != 0) {
414 			res.stat = YP_BADARGS;
415 			return (&res);
416 		}
417 
418 		ukey.ue_uid = strtonum(cp, 0, UID_MAX, &estr);
419 		if (estr) {
420 			res.stat = YP_BADARGS;
421 			return (&res);
422 		}
423 
424 		if ((ue = RB_FIND(user_uid_tree, &env->sc_user_uids,
425 		    &ukey)) == NULL) {
426 			res.stat = YP_NOKEY;
427 			return (&res);
428 		}
429 
430 		yp_make_val(&res, ue->ue_netid_line, 0);
431 		return (&res);
432 
433 	} else {
434 		log_debug("unknown map %s", arg->map);
435 		res.stat = YP_NOMAP;
436 		return (&res);
437 	}
438 }
439 
440 ypresp_key_val *
441 ypproc_first_2_svc(ypreq_nokey *arg, struct svc_req *req)
442 {
443 	static struct ypresp_key_val	res;
444 
445 	if (yp_valid_domain(arg->domain, (struct ypresp_val *)&res) == -1)
446 		return (&res);
447 
448 	if (strcmp(arg->map, "passwd.byname") == 0 ||
449 	    strcmp(arg->map, "master.passwd.byname") == 0) {
450 		if (env->sc_user_lines == NULL)
451 			return (NULL);
452 
453 		yp_make_keyval(&res, env->sc_user_lines, env->sc_user_lines);
454 	} else if (strcmp(arg->map, "group.byname") == 0) {
455 		if (env->sc_group_lines == NULL)
456 			return (NULL);
457 
458 		yp_make_keyval(&res, env->sc_group_lines, env->sc_group_lines);
459 	} else {
460 		log_debug("unknown map %s", arg->map);
461 		res.stat = YP_NOMAP;
462 	}
463 
464 	return (&res);
465 }
466 
467 ypresp_key_val *
468 ypproc_next_2_svc(ypreq_key *arg, struct svc_req *req)
469 {
470 	struct userent			 ukey;
471 	struct userent			*ue;
472 	struct groupent			 gkey;
473 	struct groupent			*ge;
474 	char				*line;
475 	static struct ypresp_key_val	 res;
476 	char				 key[YPMAXRECORD+1];
477 
478 	if (yp_valid_domain(arg->domain, (struct ypresp_val *)&res) == -1)
479 		return (&res);
480 
481 	if (strcmp(arg->map, "passwd.byname") == 0 ||
482 	    strcmp(arg->map, "master.passwd.byname") == 0) {
483 		bzero(key, sizeof(key));
484 		(void)strncpy(key, arg->key.keydat_val,
485 		    arg->key.keydat_len);
486 		ukey.ue_line = key;
487 		if ((ue = RB_FIND(user_name_tree, env->sc_user_names,
488 		    &ukey)) == NULL) {
489 			/*
490 			 * canacar's trick:
491 			 * the user might have been deleted in between calls
492 			 * to next since the tree may be modified by a reload.
493 			 * next should still return the next user in
494 			 * lexicographical order, hence insert the search key
495 			 * and look up the next field, then remove it again.
496 			 */
497 			RB_INSERT(user_name_tree, env->sc_user_names, &ukey);
498 			if ((ue = RB_NEXT(user_name_tree, &env->sc_user_names,
499 			    &ukey)) == NULL) {
500 				RB_REMOVE(user_name_tree, env->sc_user_names,
501 				    &ukey);
502 				res.stat = YP_NOKEY;
503 				return (&res);
504 			}
505 			RB_REMOVE(user_name_tree, env->sc_user_names, &ukey);
506 		}
507 		line = ue->ue_line + (strlen(ue->ue_line) + 1);
508 		line = line + (strlen(line) + 1);
509 		yp_make_keyval(&res, line, line);
510 		return (&res);
511 
512 
513 	} else if (strcmp(arg->map, "group.byname") == 0) {
514 		bzero(key, sizeof(key));
515 		(void)strncpy(key, arg->key.keydat_val,
516 		    arg->key.keydat_len);
517 
518 		gkey.ge_line = key;
519 		if ((ge = RB_FIND(group_name_tree, env->sc_group_names,
520 		    &gkey)) == NULL) {
521 			/*
522 			 * canacar's trick reloaded.
523 			 */
524 			RB_INSERT(group_name_tree, env->sc_group_names, &gkey);
525 			if ((ge = RB_NEXT(group_name_tree, &env->sc_group_names,
526 			    &gkey)) == NULL) {
527 				RB_REMOVE(group_name_tree, env->sc_group_names,
528 				    &gkey);
529 				res.stat = YP_NOKEY;
530 				return (&res);
531 			}
532 			RB_REMOVE(group_name_tree, env->sc_group_names, &gkey);
533 		}
534 
535 		line = ge->ge_line + (strlen(ge->ge_line) + 1);
536 		line = line + (strlen(line) + 1);
537 		yp_make_keyval(&res, line, line);
538 		return (&res);
539 	} else {
540 		log_debug("unknown map %s", arg->map);
541 		res.stat = YP_NOMAP;
542 		return (&res);
543 	}
544 }
545 
546 ypresp_all *
547 ypproc_all_2_svc(ypreq_nokey *arg, struct svc_req *req)
548 {
549 	static struct ypresp_all	res;
550 
551 	if (yp_valid_domain(arg->domain, (struct ypresp_val *)&res) == -1)
552 		return (&res);
553 
554 	svcerr_auth(req->rq_xprt, AUTH_FAILED);
555 	return (NULL);
556 }
557 
558 ypresp_master *
559 ypproc_master_2_svc(ypreq_nokey *arg, struct svc_req *req)
560 {
561 	static struct ypresp_master	 res;
562 
563 	if (yp_valid_domain(arg->domain, (struct ypresp_val *)&res) == -1)
564 		return (&res);
565 
566 	res.stat = YP_YPERR;
567 	return (&res);
568 }
569 
570 ypresp_maplist *
571 ypproc_maplist_2_svc(domainname *arg, struct svc_req *req)
572 {
573 	size_t			 i;
574 	static struct {
575 		char		*name;
576 		int		 cond;
577 	}			 mapnames[] = {
578 		{ "passwd.byname",		YPMAP_PASSWD_BYNAME },
579 		{ "passwd.byuid",		YPMAP_PASSWD_BYUID },
580 		{ "master.passwd.byname",	YPMAP_MASTER_PASSWD_BYNAME },
581 		{ "master.passwd.byuid",	YPMAP_MASTER_PASSWD_BYUID },
582 		{ "group.byname",		YPMAP_GROUP_BYNAME },
583 		{ "group.bygid",		YPMAP_GROUP_BYGID },
584 		{ "netid.byname",		YPMAP_NETID_BYNAME },
585 	};
586 	static ypresp_maplist	 res;
587 	static struct ypmaplist	 maps[sizeof(mapnames) / sizeof(mapnames[0])];
588 
589 	if (yp_valid_domain(*arg, (struct ypresp_val *)&res) == -1)
590 		return (&res);
591 
592 	res.stat = YP_TRUE;
593 	res.maps = NULL;
594 	for (i = 0; i < sizeof(mapnames) / sizeof(mapnames[0]); i++) {
595 		if (!(env->sc_flags & mapnames[i].cond))
596 			continue;
597 		maps[i].map = mapnames[i].name;
598 		maps[i].next = res.maps;
599 		res.maps = &maps[i];
600 	}
601 
602 	return (&res);
603 }
604 
605 void
606 yp_make_val(struct ypresp_val *res, char *line, int replacecolon)
607 {
608 	static char		 buf[LINE_WIDTH];
609 
610 	bzero(buf, sizeof(buf));
611 
612 	if (replacecolon)
613 		line[strlen(line)] = ':';
614 	(void)strlcpy(buf, line, sizeof(buf));
615 	if (replacecolon)
616 		line[strcspn(line, ":")] = '\0';
617 	log_debug("sending out %s", buf);
618 
619 	res->stat = YP_TRUE;
620 	res->val.valdat_len = strlen(buf);
621 	res->val.valdat_val = buf;
622 }
623 
624 void
625 yp_make_keyval(struct ypresp_key_val *res, char *key, char *line)
626 {
627 	static char	keybuf[YPMAXRECORD+1];
628 	static char	buf[LINE_WIDTH];
629 
630 	bzero(keybuf, sizeof(keybuf));
631 	bzero(buf, sizeof(buf));
632 
633 	(void)strlcpy(keybuf, key, sizeof(keybuf));
634 	res->key.keydat_len = strlen(keybuf);
635 	res->key.keydat_val = keybuf;
636 
637 	if (*line == '\0') {
638 		res->stat = YP_NOMORE;
639 		return;
640 	}
641 	res->stat = YP_TRUE;
642 	line[strlen(line)] = ':';
643 	(void)strlcpy(buf, line, sizeof(buf));
644 	line[strcspn(line, ":")] = '\0';
645 	log_debug("sending out %s => %s", keybuf, buf);
646 
647 	res->val.valdat_len = strlen(buf);
648 	res->val.valdat_val = buf;
649 }
650