xref: /freebsd/usr.sbin/ypldap/ypldap.c (revision 72143e89bb430c3b1406b399b810806904f6c882)
1 /*	$OpenBSD: ypldap.c,v 1.16 2015/11/02 10:06:06 jmatthew Exp $ */
2 /*	$FreeBSD */
3 
4 /*
5  * Copyright (c) 2008 Pierre-Yves Ritschard <pyr@openbsd.org>
6  *
7  * Permission to use, copy, modify, and distribute this software for any
8  * purpose with or without fee is hereby granted, provided that the above
9  * copyright notice and this permission notice appear in all copies.
10  *
11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18  */
19 
20 #include <sys/types.h>
21 #include <sys/param.h>
22 #include <sys/queue.h>
23 #include <sys/socket.h>
24 #include <sys/signal.h>
25 #include <sys/tree.h>
26 #include <sys/wait.h>
27 
28 #include <netinet/in.h>
29 #include <arpa/inet.h>
30 
31 #include <err.h>
32 #include <errno.h>
33 #include <event.h>
34 #include <unistd.h>
35 #include <pwd.h>
36 #include <stdio.h>
37 #include <stdlib.h>
38 #include <string.h>
39 #include <limits.h>
40 
41 #include "ypldap.h"
42 
43 enum ypldap_process_type		ypldap_process;
44 
45 __dead2 void	 usage(void);
46 int		 check_child(pid_t, const char *);
47 void		 main_sig_handler(int, short, void *);
48 void		 main_shutdown(void);
49 void		 main_dispatch_client(int, short, void *);
50 void		 main_configure_client(struct env *);
51 void		 main_init_timer(int, short, void *);
52 void		 main_start_update(struct env *);
53 void		 main_trash_update(struct env *);
54 void		 main_end_update(struct env *);
55 int		 main_create_user_groups(struct env *);
56 void		 purge_config(struct env *);
57 void		 reconfigure(struct env *);
58 
59 int		 pipe_main2client[2];
60 
61 pid_t		 client_pid = 0;
62 char		*conffile = YPLDAP_CONF_FILE;
63 int		 opts = 0;
64 
65 void
66 usage(void)
67 {
68 	extern const char	*__progname;
69 
70 	fprintf(stderr, "usage: %s [-dnv] [-D macro=value] [-f file]\n",
71 	    __progname);
72 	exit(1);
73 }
74 
75 int
76 check_child(pid_t pid, const char *pname)
77 {
78 	int	status;
79 
80 	if (waitpid(pid, &status, WNOHANG) > 0) {
81 		if (WIFEXITED(status)) {
82 			log_warnx("check_child: lost child %s exited", pname);
83 			return (1);
84 		}
85 		if (WIFSIGNALED(status)) {
86 			log_warnx("check_child: lost child %s terminated; "
87 			    "signal %d", pname, WTERMSIG(status));
88 			return (1);
89 		}
90 	}
91 	return (0);
92 }
93 
94 /* ARGUSED */
95 void
96 main_sig_handler(int sig, short event, void *p)
97 {
98 	int		 die = 0;
99 
100 	switch (sig) {
101 	case SIGTERM:
102 	case SIGINT:
103 		die = 1;
104 		/* FALLTHROUGH */
105 	case SIGCHLD:
106 		if (check_child(client_pid, "ldap client")) {
107 			client_pid = 0;
108 			die = 1;
109 		}
110 		if (die)
111 			main_shutdown();
112 		break;
113 	case SIGHUP:
114 		/* reconfigure */
115 		break;
116 	default:
117 		fatalx("unexpected signal");
118 	}
119 }
120 
121 void
122 main_shutdown(void)
123 {
124 	_exit(0);
125 }
126 
127 void
128 main_start_update(struct env *env)
129 {
130 	env->update_trashed = 0;
131 
132 	log_debug("starting directory update");
133 	env->sc_user_line_len = 0;
134 	env->sc_group_line_len = 0;
135 	if ((env->sc_user_names_t = calloc(1,
136 	    sizeof(*env->sc_user_names_t))) == NULL ||
137 	    (env->sc_group_names_t = calloc(1,
138 	    sizeof(*env->sc_group_names_t))) == NULL)
139 		fatal(NULL);
140 	RB_INIT(env->sc_user_names_t);
141 	RB_INIT(env->sc_group_names_t);
142 }
143 
144 /*
145  * XXX: Currently this function should only be called when updating is
146  * finished. A notification should be send to ldapclient that it should stop
147  * sending new pwd/grp entries before it can be called from different places.
148  */
149 void
150 main_trash_update(struct env *env)
151 {
152 	struct userent	*ue;
153 	struct groupent	*ge;
154 
155 	env->update_trashed = 1;
156 
157 	while ((ue = RB_ROOT(env->sc_user_names_t)) != NULL) {
158 		RB_REMOVE(user_name_tree,
159 		    env->sc_user_names_t, ue);
160 		free(ue->ue_line);
161 		free(ue->ue_netid_line);
162 		free(ue);
163 	}
164 	free(env->sc_user_names_t);
165 	env->sc_user_names_t = NULL;
166 	while ((ge = RB_ROOT(env->sc_group_names_t))
167 	    != NULL) {
168 		RB_REMOVE(group_name_tree,
169 		    env->sc_group_names_t, ge);
170 		free(ge->ge_line);
171 		free(ge);
172 	}
173 	free(env->sc_group_names_t);
174 	env->sc_group_names_t = NULL;
175 }
176 
177 int
178 main_create_user_groups(struct env *env)
179 {
180 	struct userent		*ue;
181 	struct userent		 ukey;
182 	struct groupent		*ge;
183 	gid_t			 pw_gid;
184 	char			*bp, *cp;
185 	char			*p;
186 	const char		*errstr = NULL;
187 	size_t			 len;
188 
189 	RB_FOREACH(ue, user_name_tree, env->sc_user_names_t) {
190 		bp = cp = ue->ue_line;
191 
192 		/* name */
193 		bp += strlen(bp) + 1;
194 
195 		/* password */
196 		bp += strcspn(bp, ":") + 1;
197 
198 		/* uid */
199 		bp += strcspn(bp, ":") + 1;
200 
201 		/* gid */
202 		bp[strcspn(bp, ":")] = '\0';
203 
204 		pw_gid = (gid_t)strtonum(bp, 0, GID_MAX, &errstr);
205 		if (errstr) {
206 			log_warnx("main: failed to parse gid for uid: %d\n", ue->ue_uid);
207 			return (-1);
208 		}
209 
210 		/* bring gid column back to its proper state */
211 		bp[strlen(bp)] = ':';
212 
213 		if ((ue->ue_netid_line = calloc(1, LINE_WIDTH)) == NULL) {
214 			return (-1);
215 		}
216 
217 		if (snprintf(ue->ue_netid_line, LINE_WIDTH-1, "%d:%d", ue->ue_uid, pw_gid) >= LINE_WIDTH) {
218 
219 			return (-1);
220 		}
221 
222 		ue->ue_gid = pw_gid;
223 	}
224 
225 	RB_FOREACH(ge, group_name_tree, env->sc_group_names_t) {
226 		bp = cp = ge->ge_line;
227 
228 		/* name */
229 		bp += strlen(bp) + 1;
230 
231 		/* password */
232 		bp += strcspn(bp, ":") + 1;
233 
234 		/* gid */
235 		bp += strcspn(bp, ":") + 1;
236 
237 		cp = bp;
238 		if (*bp == '\0')
239 			continue;
240 		bp = cp;
241 		for (;;) {
242 			if (!(cp = strsep(&bp, ",")))
243 				break;
244 			ukey.ue_line = cp;
245 			if ((ue = RB_FIND(user_name_tree, env->sc_user_names_t,
246 			    &ukey)) == NULL) {
247 				/* User not found */
248 				log_warnx("main: unknown user %s in group %s\n",
249 				   ukey.ue_line, ge->ge_line);
250 				if (bp != NULL)
251 					*(bp-1) = ',';
252 				continue;
253 			}
254 			if (bp != NULL)
255 				*(bp-1) = ',';
256 
257 			/* Make sure the new group doesn't equal to the main gid */
258 			if (ge->ge_gid == ue->ue_gid)
259 				continue;
260 
261 			len = strlen(ue->ue_netid_line);
262 			p = ue->ue_netid_line + len;
263 
264 			if ((snprintf(p, LINE_WIDTH-len-1, ",%d",
265 				ge->ge_gid)) >= (int)(LINE_WIDTH-len)) {
266 				return (-1);
267 			}
268 		}
269 	}
270 
271 	return (0);
272 }
273 
274 void
275 main_end_update(struct env *env)
276 {
277 	struct userent		*ue;
278 	struct groupent		*ge;
279 
280 	if (env->update_trashed)
281 		return;
282 
283 	log_debug("updates are over, cleaning up trees now");
284 
285 	if (main_create_user_groups(env) == -1) {
286 		main_trash_update(env);
287 		return;
288 	}
289 
290 	if (env->sc_user_names == NULL) {
291 		env->sc_user_names = env->sc_user_names_t;
292 		env->sc_user_lines = NULL;
293 		env->sc_user_names_t = NULL;
294 
295 		env->sc_group_names = env->sc_group_names_t;
296 		env->sc_group_lines = NULL;
297 		env->sc_group_names_t = NULL;
298 
299 		flatten_entries(env);
300 		goto make_uids;
301 	}
302 
303 	/*
304 	 * clean previous tree.
305 	 */
306 	while ((ue = RB_ROOT(env->sc_user_names)) != NULL) {
307 		RB_REMOVE(user_name_tree, env->sc_user_names,
308 		    ue);
309 		free(ue->ue_netid_line);
310 		free(ue);
311 	}
312 	free(env->sc_user_names);
313 	free(env->sc_user_lines);
314 
315 	env->sc_user_names = env->sc_user_names_t;
316 	env->sc_user_lines = NULL;
317 	env->sc_user_names_t = NULL;
318 
319 	while ((ge = RB_ROOT(env->sc_group_names)) != NULL) {
320 		RB_REMOVE(group_name_tree,
321 		    env->sc_group_names, ge);
322 		free(ge);
323 	}
324 	free(env->sc_group_names);
325 	free(env->sc_group_lines);
326 
327 	env->sc_group_names = env->sc_group_names_t;
328 	env->sc_group_lines = NULL;
329 	env->sc_group_names_t = NULL;
330 
331 
332 	flatten_entries(env);
333 
334 	/*
335 	 * trees are flat now. build up uid, gid and netid trees.
336 	 */
337 
338 make_uids:
339 	RB_INIT(&env->sc_user_uids);
340 	RB_INIT(&env->sc_group_gids);
341 	RB_FOREACH(ue, user_name_tree, env->sc_user_names)
342 		RB_INSERT(user_uid_tree,
343 		    &env->sc_user_uids, ue);
344 	RB_FOREACH(ge, group_name_tree, env->sc_group_names)
345 		RB_INSERT(group_gid_tree,
346 		    &env->sc_group_gids, ge);
347 
348 }
349 
350 void
351 main_dispatch_client(int fd, short events, void *p)
352 {
353 	int		 n;
354 	int		 shut = 0;
355 	struct env	*env = p;
356 	struct imsgev	*iev = env->sc_iev;
357 	struct imsgbuf	*ibuf = &iev->ibuf;
358 	struct idm_req	 ir;
359 	struct imsg	 imsg;
360 
361 	if ((events & (EV_READ | EV_WRITE)) == 0)
362 		fatalx("unknown event");
363 
364 	if (events & EV_READ) {
365 		if ((n = imsg_read(ibuf)) == -1 && errno != EAGAIN)
366 			fatal("imsg_read error");
367 		if (n == 0)
368 			shut = 1;
369 	}
370 	if (events & EV_WRITE) {
371 		if ((n = msgbuf_write(&ibuf->w)) == -1 && errno != EAGAIN)
372 			fatal("msgbuf_write");
373 		if (n == 0)
374 			shut = 1;
375 		goto done;
376 	}
377 
378 	for (;;) {
379 		if ((n = imsg_get(ibuf, &imsg)) == -1)
380 			fatal("main_dispatch_client: imsg_get error");
381 		if (n == 0)
382 			break;
383 
384 		switch (imsg.hdr.type) {
385 		case IMSG_START_UPDATE:
386 			main_start_update(env);
387 			break;
388 		case IMSG_PW_ENTRY: {
389 			struct userent	*ue;
390 			size_t		 len;
391 
392 			if (env->update_trashed)
393 				break;
394 
395 			(void)memcpy(&ir, imsg.data, sizeof(ir));
396 			if ((ue = calloc(1, sizeof(*ue))) == NULL ||
397 			    (ue->ue_line = strdup(ir.ir_line)) == NULL) {
398 				/*
399 				 * should cancel tree update instead.
400 				 */
401 				fatal("out of memory");
402 			}
403 			ue->ue_uid = ir.ir_key.ik_uid;
404 			len = strlen(ue->ue_line) + 1;
405 			ue->ue_line[strcspn(ue->ue_line, ":")] = '\0';
406 			if (RB_INSERT(user_name_tree, env->sc_user_names_t,
407 			    ue) != NULL) { /* dup */
408 				free(ue->ue_line);
409 				free(ue);
410 			} else
411 				env->sc_user_line_len += len;
412 			break;
413 		}
414 		case IMSG_GRP_ENTRY: {
415 			struct groupent	*ge;
416 			size_t		 len;
417 
418 			if (env->update_trashed)
419 				break;
420 
421 			(void)memcpy(&ir, imsg.data, sizeof(ir));
422 			if ((ge = calloc(1, sizeof(*ge))) == NULL ||
423 			    (ge->ge_line = strdup(ir.ir_line)) == NULL) {
424 				/*
425 				 * should cancel tree update instead.
426 				 */
427 				fatal("out of memory");
428 			}
429 			ge->ge_gid = ir.ir_key.ik_gid;
430 			len = strlen(ge->ge_line) + 1;
431 			ge->ge_line[strcspn(ge->ge_line, ":")] = '\0';
432 			if (RB_INSERT(group_name_tree, env->sc_group_names_t,
433 			    ge) != NULL) { /* dup */
434 				free(ge->ge_line);
435 				free(ge);
436 			} else
437 				env->sc_group_line_len += len;
438 			break;
439 		}
440 		case IMSG_TRASH_UPDATE:
441 			main_trash_update(env);
442 			break;
443 		case IMSG_END_UPDATE: {
444 			main_end_update(env);
445 			break;
446 		}
447 		default:
448 			log_debug("main_dispatch_client: unexpected imsg %d",
449 			   imsg.hdr.type);
450 			break;
451 		}
452 		imsg_free(&imsg);
453 	}
454 
455 done:
456 	if (!shut)
457 		imsg_event_add(iev);
458 	else {
459 		log_debug("king bula sez: ran into dead pipe");
460 		event_del(&iev->ev);
461 		event_loopexit(NULL);
462 	}
463 }
464 
465 void
466 main_configure_client(struct env *env)
467 {
468 	struct idm	*idm;
469 	struct imsgev	*iev = env->sc_iev;
470 
471 	imsg_compose_event(iev, IMSG_CONF_START, 0, 0, -1, env, sizeof(*env));
472 	TAILQ_FOREACH(idm, &env->sc_idms, idm_entry) {
473 		imsg_compose_event(iev, IMSG_CONF_IDM, 0, 0, -1,
474 		    idm, sizeof(*idm));
475 	}
476 	imsg_compose_event(iev, IMSG_CONF_END, 0, 0, -1, NULL, 0);
477 }
478 
479 void
480 main_init_timer(int fd, short event, void *p)
481 {
482 	struct env	*env = p;
483 
484 	main_configure_client(env);
485 }
486 
487 void
488 purge_config(struct env *env)
489 {
490 	struct idm	*idm;
491 
492 	while ((idm = TAILQ_FIRST(&env->sc_idms)) != NULL) {
493 		TAILQ_REMOVE(&env->sc_idms, idm, idm_entry);
494 		free(idm);
495 	}
496 }
497 
498 int
499 main(int argc, char *argv[])
500 {
501 	int		 c;
502 	int		 debug;
503 	struct passwd	*pw;
504 	struct env	 env;
505 	struct event	 ev_sigint;
506 	struct event	 ev_sigterm;
507 	struct event	 ev_sigchld;
508 	struct event	 ev_sighup;
509 	struct event	 ev_timer;
510 	struct timeval	 tv;
511 
512 	debug = 0;
513 	ypldap_process = PROC_MAIN;
514 
515 	log_init(1);
516 
517 	while ((c = getopt(argc, argv, "dD:nf:v")) != -1) {
518 		switch (c) {
519 		case 'd':
520 			debug = 2;
521 			break;
522 		case 'D':
523 			if (cmdline_symset(optarg) < 0)
524 				log_warnx("could not parse macro definition %s",
525 				    optarg);
526 			break;
527 		case 'n':
528 			debug = 2;
529 			opts |= YPLDAP_OPT_NOACTION;
530 			break;
531 		case 'f':
532 			conffile = optarg;
533 			break;
534 		case 'v':
535 			opts |= YPLDAP_OPT_VERBOSE;
536 			break;
537 		default:
538 			usage();
539 		}
540 	}
541 
542 	argc -= optind;
543 	argv += optind;
544 
545 	if (argc)
546 		usage();
547 
548 	RB_INIT(&env.sc_user_uids);
549 	RB_INIT(&env.sc_group_gids);
550 
551 	if (parse_config(&env, conffile, opts))
552 		exit(1);
553 	if (opts & YPLDAP_OPT_NOACTION) {
554 		fprintf(stderr, "configuration OK\n");
555 		exit(0);
556 	}
557 
558 	if (geteuid())
559 		errx(1, "need root privileges");
560 
561 	log_init(debug);
562 
563 	if (!debug) {
564 		if (daemon(1, 0) == -1)
565 			err(1, "failed to daemonize");
566 	}
567 
568 	log_info("startup%s", (debug > 1)?" [debug mode]":"");
569 
570 	if (socketpair(AF_UNIX, SOCK_STREAM | SOCK_NONBLOCK, PF_UNSPEC,
571 	    pipe_main2client) == -1)
572 		fatal("socketpair");
573 
574 	client_pid = ldapclient(pipe_main2client);
575 
576 	setproctitle("parent");
577 	event_init();
578 
579 	signal_set(&ev_sigint, SIGINT, main_sig_handler, &env);
580 	signal_set(&ev_sigterm, SIGTERM, main_sig_handler, &env);
581 	signal_set(&ev_sighup, SIGHUP, main_sig_handler, &env);
582 	signal_set(&ev_sigchld, SIGCHLD, main_sig_handler, &env);
583 	signal_add(&ev_sigint, NULL);
584 	signal_add(&ev_sigterm, NULL);
585 	signal_add(&ev_sighup, NULL);
586 	signal_add(&ev_sigchld, NULL);
587 
588 	close(pipe_main2client[1]);
589 	if ((env.sc_iev = calloc(1, sizeof(*env.sc_iev))) == NULL)
590 		fatal(NULL);
591 	imsg_init(&env.sc_iev->ibuf, pipe_main2client[0]);
592 	env.sc_iev->handler = main_dispatch_client;
593 
594 	env.sc_iev->events = EV_READ;
595 	env.sc_iev->data = &env;
596 	event_set(&env.sc_iev->ev, env.sc_iev->ibuf.fd, env.sc_iev->events,
597 	     env.sc_iev->handler, &env);
598 	event_add(&env.sc_iev->ev, NULL);
599 
600 	yp_init(&env);
601 
602 	if ((pw = getpwnam(YPLDAP_USER)) == NULL)
603 		fatal("getpwnam");
604 
605 #ifndef DEBUG
606 	if (setgroups(1, &pw->pw_gid) ||
607 	    setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) ||
608 	    setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid))
609 		fatal("cannot drop privileges");
610 #else
611 #warning disabling privilege revocation in debug mode
612 #endif
613 
614 	memset(&tv, 0, sizeof(tv));
615 	evtimer_set(&ev_timer, main_init_timer, &env);
616 	evtimer_add(&ev_timer, &tv);
617 
618 	yp_enable_events();
619 	event_dispatch();
620 	main_shutdown();
621 
622 	return (0);
623 }
624 
625 void
626 imsg_event_add(struct imsgev *iev)
627 {
628 	if (iev->handler == NULL) {
629 		imsg_flush(&iev->ibuf);
630 		return;
631 	}
632 
633 	iev->events = EV_READ;
634 	if (iev->ibuf.w.queued)
635 		iev->events |= EV_WRITE;
636 
637 	event_del(&iev->ev);
638 	event_set(&iev->ev, iev->ibuf.fd, iev->events, iev->handler, iev->data);
639 	event_add(&iev->ev, NULL);
640 }
641 
642 int
643 imsg_compose_event(struct imsgev *iev, u_int16_t type, u_int32_t peerid,
644     pid_t pid, int fd, void *data, u_int16_t datalen)
645 {
646 	int	ret;
647 
648 	if ((ret = imsg_compose(&iev->ibuf, type, peerid,
649 	    pid, fd, data, datalen)) != -1)
650 		imsg_event_add(iev);
651 	return (ret);
652 }
653