xref: /freebsd/usr.sbin/ypldap/ypldap.c (revision e5b786625f7f82a1fa91e41823332459ea5550f9)
1 /*	$OpenBSD: ypldap.c,v 1.16 2015/11/02 10:06:06 jmatthew Exp $ */
2 
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/signal.h>
24 #include <sys/tree.h>
25 #include <sys/wait.h>
26 
27 #include <netinet/in.h>
28 #include <arpa/inet.h>
29 
30 #include <err.h>
31 #include <errno.h>
32 #include <event.h>
33 #include <unistd.h>
34 #include <pwd.h>
35 #include <stdio.h>
36 #include <stdlib.h>
37 #include <string.h>
38 #include <limits.h>
39 
40 #include "ypldap.h"
41 
42 enum ypldap_process_type		ypldap_process;
43 
44 __dead2 void	 usage(void);
45 int		 check_child(pid_t, const char *);
46 void		 main_sig_handler(int, short, void *);
47 void		 main_shutdown(void);
48 void		 main_dispatch_client(int, short, void *);
49 void		 main_configure_client(struct env *);
50 void		 main_init_timer(int, short, void *);
51 void		 main_start_update(struct env *);
52 void		 main_trash_update(struct env *);
53 void		 main_end_update(struct env *);
54 int		 main_create_user_groups(struct env *);
55 void		 purge_config(struct env *);
56 void		 reconfigure(struct env *);
57 
58 int		 pipe_main2client[2];
59 
60 pid_t		 client_pid = 0;
61 char		*conffile = YPLDAP_CONF_FILE;
62 int		 opts = 0;
63 
64 void
65 usage(void)
66 {
67 	extern const char	*__progname;
68 
69 	fprintf(stderr, "usage: %s [-dnv] [-D macro=value] [-f file]\n",
70 	    __progname);
71 	exit(1);
72 }
73 
74 int
75 check_child(pid_t pid, const char *pname)
76 {
77 	int	status;
78 
79 	if (waitpid(pid, &status, WNOHANG) > 0) {
80 		if (WIFEXITED(status)) {
81 			log_warnx("check_child: lost child %s exited", pname);
82 			return (1);
83 		}
84 		if (WIFSIGNALED(status)) {
85 			log_warnx("check_child: lost child %s terminated; "
86 			    "signal %d", pname, WTERMSIG(status));
87 			return (1);
88 		}
89 	}
90 	return (0);
91 }
92 
93 /* ARGUSED */
94 void
95 main_sig_handler(int sig, short event, void *p)
96 {
97 	int		 die = 0;
98 
99 	switch (sig) {
100 	case SIGTERM:
101 	case SIGINT:
102 		die = 1;
103 		/* FALLTHROUGH */
104 	case SIGCHLD:
105 		if (check_child(client_pid, "ldap client")) {
106 			client_pid = 0;
107 			die = 1;
108 		}
109 		if (die)
110 			main_shutdown();
111 		break;
112 	case SIGHUP:
113 		/* reconfigure */
114 		break;
115 	default:
116 		fatalx("unexpected signal");
117 	}
118 }
119 
120 void
121 main_shutdown(void)
122 {
123 	_exit(0);
124 }
125 
126 void
127 main_start_update(struct env *env)
128 {
129 	env->update_trashed = 0;
130 
131 	log_debug("starting directory update");
132 	env->sc_user_line_len = 0;
133 	env->sc_group_line_len = 0;
134 	if ((env->sc_user_names_t = calloc(1,
135 	    sizeof(*env->sc_user_names_t))) == NULL ||
136 	    (env->sc_group_names_t = calloc(1,
137 	    sizeof(*env->sc_group_names_t))) == NULL)
138 		fatal(NULL);
139 	RB_INIT(env->sc_user_names_t);
140 	RB_INIT(env->sc_group_names_t);
141 }
142 
143 /*
144  * XXX: Currently this function should only be called when updating is
145  * finished. A notification should be send to ldapclient that it should stop
146  * sending new pwd/grp entries before it can be called from different places.
147  */
148 void
149 main_trash_update(struct env *env)
150 {
151 	struct userent	*ue;
152 	struct groupent	*ge;
153 
154 	env->update_trashed = 1;
155 
156 	while ((ue = RB_ROOT(env->sc_user_names_t)) != NULL) {
157 		RB_REMOVE(user_name_tree,
158 		    env->sc_user_names_t, ue);
159 		free(ue->ue_line);
160 		free(ue->ue_netid_line);
161 		free(ue);
162 	}
163 	free(env->sc_user_names_t);
164 	env->sc_user_names_t = NULL;
165 	while ((ge = RB_ROOT(env->sc_group_names_t))
166 	    != NULL) {
167 		RB_REMOVE(group_name_tree,
168 		    env->sc_group_names_t, ge);
169 		free(ge->ge_line);
170 		free(ge);
171 	}
172 	free(env->sc_group_names_t);
173 	env->sc_group_names_t = NULL;
174 }
175 
176 int
177 main_create_user_groups(struct env *env)
178 {
179 	struct userent		*ue;
180 	struct userent		 ukey;
181 	struct groupent		*ge;
182 	gid_t			 pw_gid;
183 	char			*bp, *cp;
184 	char			*p;
185 	const char		*errstr = NULL;
186 	size_t			 len;
187 
188 	RB_FOREACH(ue, user_name_tree, env->sc_user_names_t) {
189 		bp = cp = ue->ue_line;
190 
191 		/* name */
192 		bp += strlen(bp) + 1;
193 
194 		/* password */
195 		bp += strcspn(bp, ":") + 1;
196 
197 		/* uid */
198 		bp += strcspn(bp, ":") + 1;
199 
200 		/* gid */
201 		bp[strcspn(bp, ":")] = '\0';
202 
203 		pw_gid = (gid_t)strtonum(bp, 0, GID_MAX, &errstr);
204 		if (errstr) {
205 			log_warnx("main: failed to parse gid for uid: %d\n", ue->ue_uid);
206 			return (-1);
207 		}
208 
209 		/* bring gid column back to its proper state */
210 		bp[strlen(bp)] = ':';
211 
212 		if ((ue->ue_netid_line = calloc(1, LINE_WIDTH)) == NULL) {
213 			return (-1);
214 		}
215 
216 		if (snprintf(ue->ue_netid_line, LINE_WIDTH-1, "%d:%d", ue->ue_uid, pw_gid) >= LINE_WIDTH) {
217 
218 			return (-1);
219 		}
220 
221 		ue->ue_gid = pw_gid;
222 	}
223 
224 	RB_FOREACH(ge, group_name_tree, env->sc_group_names_t) {
225 		bp = cp = ge->ge_line;
226 
227 		/* name */
228 		bp += strlen(bp) + 1;
229 
230 		/* password */
231 		bp += strcspn(bp, ":") + 1;
232 
233 		/* gid */
234 		bp += strcspn(bp, ":") + 1;
235 
236 		cp = bp;
237 		if (*bp == '\0')
238 			continue;
239 		bp = cp;
240 		for (;;) {
241 			if (!(cp = strsep(&bp, ",")))
242 				break;
243 			ukey.ue_line = cp;
244 			if ((ue = RB_FIND(user_name_tree, env->sc_user_names_t,
245 			    &ukey)) == NULL) {
246 				/* User not found */
247 				log_warnx("main: unknown user %s in group %s\n",
248 				   ukey.ue_line, ge->ge_line);
249 				if (bp != NULL)
250 					*(bp-1) = ',';
251 				continue;
252 			}
253 			if (bp != NULL)
254 				*(bp-1) = ',';
255 
256 			/* Make sure the new group doesn't equal to the main gid */
257 			if (ge->ge_gid == ue->ue_gid)
258 				continue;
259 
260 			len = strlen(ue->ue_netid_line);
261 			p = ue->ue_netid_line + len;
262 
263 			if ((snprintf(p, LINE_WIDTH-len-1, ",%d",
264 				ge->ge_gid)) >= (int)(LINE_WIDTH-len)) {
265 				return (-1);
266 			}
267 		}
268 	}
269 
270 	return (0);
271 }
272 
273 void
274 main_end_update(struct env *env)
275 {
276 	struct userent		*ue;
277 	struct groupent		*ge;
278 
279 	if (env->update_trashed)
280 		return;
281 
282 	log_debug("updates are over, cleaning up trees now");
283 
284 	if (main_create_user_groups(env) == -1) {
285 		main_trash_update(env);
286 		return;
287 	}
288 
289 	if (env->sc_user_names == NULL) {
290 		env->sc_user_names = env->sc_user_names_t;
291 		env->sc_user_lines = NULL;
292 		env->sc_user_names_t = NULL;
293 
294 		env->sc_group_names = env->sc_group_names_t;
295 		env->sc_group_lines = NULL;
296 		env->sc_group_names_t = NULL;
297 
298 		flatten_entries(env);
299 		goto make_uids;
300 	}
301 
302 	/*
303 	 * clean previous tree.
304 	 */
305 	while ((ue = RB_ROOT(env->sc_user_names)) != NULL) {
306 		RB_REMOVE(user_name_tree, env->sc_user_names,
307 		    ue);
308 		free(ue->ue_netid_line);
309 		free(ue);
310 	}
311 	free(env->sc_user_names);
312 	free(env->sc_user_lines);
313 
314 	env->sc_user_names = env->sc_user_names_t;
315 	env->sc_user_lines = NULL;
316 	env->sc_user_names_t = NULL;
317 
318 	while ((ge = RB_ROOT(env->sc_group_names)) != NULL) {
319 		RB_REMOVE(group_name_tree,
320 		    env->sc_group_names, ge);
321 		free(ge);
322 	}
323 	free(env->sc_group_names);
324 	free(env->sc_group_lines);
325 
326 	env->sc_group_names = env->sc_group_names_t;
327 	env->sc_group_lines = NULL;
328 	env->sc_group_names_t = NULL;
329 
330 
331 	flatten_entries(env);
332 
333 	/*
334 	 * trees are flat now. build up uid, gid and netid trees.
335 	 */
336 
337 make_uids:
338 	RB_INIT(&env->sc_user_uids);
339 	RB_INIT(&env->sc_group_gids);
340 	RB_FOREACH(ue, user_name_tree, env->sc_user_names)
341 		RB_INSERT(user_uid_tree,
342 		    &env->sc_user_uids, ue);
343 	RB_FOREACH(ge, group_name_tree, env->sc_group_names)
344 		RB_INSERT(group_gid_tree,
345 		    &env->sc_group_gids, ge);
346 
347 }
348 
349 void
350 main_dispatch_client(int fd, short events, void *p)
351 {
352 	int		 n;
353 	int		 shut = 0;
354 	struct env	*env = p;
355 	struct imsgev	*iev = env->sc_iev;
356 	struct imsgbuf	*ibuf = &iev->ibuf;
357 	struct idm_req	 ir;
358 	struct imsg	 imsg;
359 
360 	if ((events & (EV_READ | EV_WRITE)) == 0)
361 		fatalx("unknown event");
362 
363 	if (events & EV_READ) {
364 		if ((n = imsg_read(ibuf)) == -1 && errno != EAGAIN)
365 			fatal("imsg_read error");
366 		if (n == 0)
367 			shut = 1;
368 	}
369 	if (events & EV_WRITE) {
370 		if ((n = msgbuf_write(&ibuf->w)) == -1 && errno != EAGAIN)
371 			fatal("msgbuf_write");
372 		if (n == 0)
373 			shut = 1;
374 		goto done;
375 	}
376 
377 	for (;;) {
378 		if ((n = imsg_get(ibuf, &imsg)) == -1)
379 			fatal("main_dispatch_client: imsg_get error");
380 		if (n == 0)
381 			break;
382 
383 		switch (imsg.hdr.type) {
384 		case IMSG_START_UPDATE:
385 			main_start_update(env);
386 			break;
387 		case IMSG_PW_ENTRY: {
388 			struct userent	*ue;
389 			size_t		 len;
390 
391 			if (env->update_trashed)
392 				break;
393 
394 			(void)memcpy(&ir, imsg.data, sizeof(ir));
395 			if ((ue = calloc(1, sizeof(*ue))) == NULL ||
396 			    (ue->ue_line = strdup(ir.ir_line)) == NULL) {
397 				/*
398 				 * should cancel tree update instead.
399 				 */
400 				fatal("out of memory");
401 			}
402 			ue->ue_uid = ir.ir_key.ik_uid;
403 			len = strlen(ue->ue_line) + 1;
404 			ue->ue_line[strcspn(ue->ue_line, ":")] = '\0';
405 			if (RB_INSERT(user_name_tree, env->sc_user_names_t,
406 			    ue) != NULL) { /* dup */
407 				free(ue->ue_line);
408 				free(ue);
409 			} else
410 				env->sc_user_line_len += len;
411 			break;
412 		}
413 		case IMSG_GRP_ENTRY: {
414 			struct groupent	*ge;
415 			size_t		 len;
416 
417 			if (env->update_trashed)
418 				break;
419 
420 			(void)memcpy(&ir, imsg.data, sizeof(ir));
421 			if ((ge = calloc(1, sizeof(*ge))) == NULL ||
422 			    (ge->ge_line = strdup(ir.ir_line)) == NULL) {
423 				/*
424 				 * should cancel tree update instead.
425 				 */
426 				fatal("out of memory");
427 			}
428 			ge->ge_gid = ir.ir_key.ik_gid;
429 			len = strlen(ge->ge_line) + 1;
430 			ge->ge_line[strcspn(ge->ge_line, ":")] = '\0';
431 			if (RB_INSERT(group_name_tree, env->sc_group_names_t,
432 			    ge) != NULL) { /* dup */
433 				free(ge->ge_line);
434 				free(ge);
435 			} else
436 				env->sc_group_line_len += len;
437 			break;
438 		}
439 		case IMSG_TRASH_UPDATE:
440 			main_trash_update(env);
441 			break;
442 		case IMSG_END_UPDATE: {
443 			main_end_update(env);
444 			break;
445 		}
446 		default:
447 			log_debug("main_dispatch_client: unexpected imsg %d",
448 			   imsg.hdr.type);
449 			break;
450 		}
451 		imsg_free(&imsg);
452 	}
453 
454 done:
455 	if (!shut)
456 		imsg_event_add(iev);
457 	else {
458 		log_debug("king bula sez: ran into dead pipe");
459 		event_del(&iev->ev);
460 		event_loopexit(NULL);
461 	}
462 }
463 
464 void
465 main_configure_client(struct env *env)
466 {
467 	struct idm	*idm;
468 	struct imsgev	*iev = env->sc_iev;
469 
470 	imsg_compose_event(iev, IMSG_CONF_START, 0, 0, -1, env, sizeof(*env));
471 	TAILQ_FOREACH(idm, &env->sc_idms, idm_entry) {
472 		imsg_compose_event(iev, IMSG_CONF_IDM, 0, 0, -1,
473 		    idm, sizeof(*idm));
474 	}
475 	imsg_compose_event(iev, IMSG_CONF_END, 0, 0, -1, NULL, 0);
476 }
477 
478 void
479 main_init_timer(int fd, short event, void *p)
480 {
481 	struct env	*env = p;
482 
483 	main_configure_client(env);
484 }
485 
486 void
487 purge_config(struct env *env)
488 {
489 	struct idm	*idm;
490 
491 	while ((idm = TAILQ_FIRST(&env->sc_idms)) != NULL) {
492 		TAILQ_REMOVE(&env->sc_idms, idm, idm_entry);
493 		free(idm);
494 	}
495 }
496 
497 int
498 main(int argc, char *argv[])
499 {
500 	int		 c;
501 	int		 debug;
502 	struct passwd	*pw;
503 	struct env	 env;
504 	struct event	 ev_sigint;
505 	struct event	 ev_sigterm;
506 	struct event	 ev_sigchld;
507 	struct event	 ev_sighup;
508 	struct event	 ev_timer;
509 	struct timeval	 tv;
510 
511 	debug = 0;
512 	ypldap_process = PROC_MAIN;
513 
514 	log_init(1);
515 
516 	while ((c = getopt(argc, argv, "dD:nf:v")) != -1) {
517 		switch (c) {
518 		case 'd':
519 			debug = 2;
520 			break;
521 		case 'D':
522 			if (cmdline_symset(optarg) < 0)
523 				log_warnx("could not parse macro definition %s",
524 				    optarg);
525 			break;
526 		case 'n':
527 			debug = 2;
528 			opts |= YPLDAP_OPT_NOACTION;
529 			break;
530 		case 'f':
531 			conffile = optarg;
532 			break;
533 		case 'v':
534 			opts |= YPLDAP_OPT_VERBOSE;
535 			break;
536 		default:
537 			usage();
538 		}
539 	}
540 
541 	argc -= optind;
542 	argv += optind;
543 
544 	if (argc)
545 		usage();
546 
547 	RB_INIT(&env.sc_user_uids);
548 	RB_INIT(&env.sc_group_gids);
549 
550 	if (parse_config(&env, conffile, opts))
551 		exit(1);
552 	if (opts & YPLDAP_OPT_NOACTION) {
553 		fprintf(stderr, "configuration OK\n");
554 		exit(0);
555 	}
556 
557 	if (geteuid())
558 		errx(1, "need root privileges");
559 
560 	log_init(debug);
561 
562 	if (!debug) {
563 		if (daemon(1, 0) == -1)
564 			err(1, "failed to daemonize");
565 	}
566 
567 	log_info("startup%s", (debug > 1)?" [debug mode]":"");
568 
569 	if (socketpair(AF_UNIX, SOCK_STREAM | SOCK_NONBLOCK, PF_UNSPEC,
570 	    pipe_main2client) == -1)
571 		fatal("socketpair");
572 
573 	client_pid = ldapclient(pipe_main2client);
574 
575 	setproctitle("parent");
576 	event_init();
577 
578 	signal_set(&ev_sigint, SIGINT, main_sig_handler, &env);
579 	signal_set(&ev_sigterm, SIGTERM, main_sig_handler, &env);
580 	signal_set(&ev_sighup, SIGHUP, main_sig_handler, &env);
581 	signal_set(&ev_sigchld, SIGCHLD, main_sig_handler, &env);
582 	signal_add(&ev_sigint, NULL);
583 	signal_add(&ev_sigterm, NULL);
584 	signal_add(&ev_sighup, NULL);
585 	signal_add(&ev_sigchld, NULL);
586 
587 	close(pipe_main2client[1]);
588 	if ((env.sc_iev = calloc(1, sizeof(*env.sc_iev))) == NULL)
589 		fatal(NULL);
590 	imsg_init(&env.sc_iev->ibuf, pipe_main2client[0]);
591 	env.sc_iev->handler = main_dispatch_client;
592 
593 	env.sc_iev->events = EV_READ;
594 	env.sc_iev->data = &env;
595 	event_set(&env.sc_iev->ev, env.sc_iev->ibuf.fd, env.sc_iev->events,
596 	     env.sc_iev->handler, &env);
597 	event_add(&env.sc_iev->ev, NULL);
598 
599 	yp_init(&env);
600 
601 	if ((pw = getpwnam(YPLDAP_USER)) == NULL)
602 		fatal("getpwnam");
603 
604 #ifndef DEBUG
605 	if (setgroups(1, &pw->pw_gid) ||
606 	    setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) ||
607 	    setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid))
608 		fatal("cannot drop privileges");
609 #else
610 #warning disabling privilege revocation in debug mode
611 #endif
612 
613 	memset(&tv, 0, sizeof(tv));
614 	evtimer_set(&ev_timer, main_init_timer, &env);
615 	evtimer_add(&ev_timer, &tv);
616 
617 	yp_enable_events();
618 	event_dispatch();
619 	main_shutdown();
620 
621 	return (0);
622 }
623 
624 void
625 imsg_event_add(struct imsgev *iev)
626 {
627 	if (iev->handler == NULL) {
628 		imsg_flush(&iev->ibuf);
629 		return;
630 	}
631 
632 	iev->events = EV_READ;
633 	if (iev->ibuf.w.queued)
634 		iev->events |= EV_WRITE;
635 
636 	event_del(&iev->ev);
637 	event_set(&iev->ev, iev->ibuf.fd, iev->events, iev->handler, iev->data);
638 	event_add(&iev->ev, NULL);
639 }
640 
641 int
642 imsg_compose_event(struct imsgev *iev, u_int16_t type, u_int32_t peerid,
643     pid_t pid, int fd, void *data, u_int16_t datalen)
644 {
645 	int	ret;
646 
647 	if ((ret = imsg_compose(&iev->ibuf, type, peerid,
648 	    pid, fd, data, datalen)) != -1)
649 		imsg_event_add(iev);
650 	return (ret);
651 }
652