xref: /freebsd/usr.sbin/autofs/common.c (revision 22cf89c938886d14f5796fc49f9f020c23ea8eaf)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2014 The FreeBSD Foundation
5  *
6  * This software was developed by Edward Tomasz Napierala under sponsorship
7  * from the FreeBSD Foundation.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  *
30  */
31 
32 #include <sys/cdefs.h>
33 #include <sys/types.h>
34 #include <sys/time.h>
35 #include <sys/ioctl.h>
36 #include <sys/param.h>
37 #include <sys/linker.h>
38 #include <sys/mount.h>
39 #include <sys/socket.h>
40 #include <sys/stat.h>
41 #include <sys/wait.h>
42 #include <sys/utsname.h>
43 #include <assert.h>
44 #include <ctype.h>
45 #include <err.h>
46 #include <errno.h>
47 #include <fcntl.h>
48 #include <libgen.h>
49 #include <libutil.h>
50 #include <netdb.h>
51 #include <paths.h>
52 #include <signal.h>
53 #include <stdbool.h>
54 #include <stdint.h>
55 #include <stdio.h>
56 #include <stdlib.h>
57 #include <string.h>
58 #include <unistd.h>
59 
60 #include "autofs_ioctl.h"
61 
62 #include "common.h"
63 
64 extern FILE *yyin;
65 extern char *yytext;
66 extern int yylex(void);
67 
68 static void	parse_master_yyin(struct node *root, const char *master);
69 static void	parse_map_yyin(struct node *parent, const char *map,
70 		    const char *executable_key);
71 
72 char *
73 checked_strdup(const char *s)
74 {
75 	char *c;
76 
77 	assert(s != NULL);
78 
79 	c = strdup(s);
80 	if (c == NULL)
81 		log_err(1, "strdup");
82 	return (c);
83 }
84 
85 /*
86  * Concatenate two strings, inserting separator between them, unless not needed.
87  */
88 char *
89 concat(const char *s1, char separator, const char *s2)
90 {
91 	char *result;
92 	char s1last, s2first;
93 	int ret;
94 
95 	if (s1 == NULL)
96 		s1 = "";
97 	if (s2 == NULL)
98 		s2 = "";
99 
100 	if (s1[0] == '\0')
101 		s1last = '\0';
102 	else
103 		s1last = s1[strlen(s1) - 1];
104 
105 	s2first = s2[0];
106 
107 	if (s1last == separator && s2first == separator) {
108 		/*
109 		 * If s1 ends with the separator and s2 begins with
110 		 * it - skip the latter; otherwise concatenating "/"
111 		 * and "/foo" would end up returning "//foo".
112 		 */
113 		ret = asprintf(&result, "%s%s", s1, s2 + 1);
114 	} else if (s1last == separator || s2first == separator ||
115 	    s1[0] == '\0' || s2[0] == '\0') {
116 		ret = asprintf(&result, "%s%s", s1, s2);
117 	} else {
118 		ret = asprintf(&result, "%s%c%s", s1, separator, s2);
119 	}
120 	if (ret < 0)
121 		log_err(1, "asprintf");
122 
123 	//log_debugx("%s: got %s and %s, returning %s", __func__, s1, s2, result);
124 
125 	return (result);
126 }
127 
128 void
129 create_directory(const char *path)
130 {
131 	char *component, *copy, *tofree, *partial, *tmp;
132 	int error;
133 
134 	assert(path[0] == '/');
135 
136 	/*
137 	 * +1 to skip the leading slash.
138 	 */
139 	copy = tofree = checked_strdup(path + 1);
140 
141 	partial = checked_strdup("/");
142 	for (;;) {
143 		component = strsep(&copy, "/");
144 		if (component == NULL)
145 			break;
146 		tmp = concat(partial, '/', component);
147 		free(partial);
148 		partial = tmp;
149 		//log_debugx("creating \"%s\"", partial);
150 		error = mkdir(partial, 0755);
151 		if (error != 0 && errno != EEXIST) {
152 			log_warn("cannot create %s", partial);
153 			return;
154 		}
155 	}
156 
157 	free(tofree);
158 }
159 
160 struct node *
161 node_new_root(void)
162 {
163 	struct node *n;
164 
165 	n = calloc(1, sizeof(*n));
166 	if (n == NULL)
167 		log_err(1, "calloc");
168 	// XXX
169 	n->n_key = checked_strdup("/");
170 	n->n_options = checked_strdup("");
171 
172 	TAILQ_INIT(&n->n_children);
173 
174 	return (n);
175 }
176 
177 struct node *
178 node_new(struct node *parent, char *key, char *options, char *location,
179     const char *config_file, int config_line)
180 {
181 	struct node *n;
182 
183 	n = calloc(1, sizeof(*n));
184 	if (n == NULL)
185 		log_err(1, "calloc");
186 
187 	TAILQ_INIT(&n->n_children);
188 	assert(key != NULL);
189 	assert(key[0] != '\0');
190 	n->n_key = key;
191 	if (options != NULL)
192 		n->n_options = options;
193 	else
194 		n->n_options = strdup("");
195 	n->n_location = location;
196 	assert(config_file != NULL);
197 	n->n_config_file = config_file;
198 	assert(config_line >= 0);
199 	n->n_config_line = config_line;
200 
201 	assert(parent != NULL);
202 	n->n_parent = parent;
203 	TAILQ_INSERT_TAIL(&parent->n_children, n, n_next);
204 
205 	return (n);
206 }
207 
208 struct node *
209 node_new_map(struct node *parent, char *key, char *options, char *map,
210     const char *config_file, int config_line)
211 {
212 	struct node *n;
213 
214 	n = calloc(1, sizeof(*n));
215 	if (n == NULL)
216 		log_err(1, "calloc");
217 
218 	TAILQ_INIT(&n->n_children);
219 	assert(key != NULL);
220 	assert(key[0] != '\0');
221 	n->n_key = key;
222 	if (options != NULL)
223 		n->n_options = options;
224 	else
225 		n->n_options = strdup("");
226 	n->n_map = map;
227 	assert(config_file != NULL);
228 	n->n_config_file = config_file;
229 	assert(config_line >= 0);
230 	n->n_config_line = config_line;
231 
232 	assert(parent != NULL);
233 	n->n_parent = parent;
234 	TAILQ_INSERT_TAIL(&parent->n_children, n, n_next);
235 
236 	return (n);
237 }
238 
239 static struct node *
240 node_duplicate(const struct node *o, struct node *parent)
241 {
242 	const struct node *child;
243 	struct node *n;
244 
245 	if (parent == NULL)
246 		parent = o->n_parent;
247 
248 	n = node_new(parent, o->n_key, o->n_options, o->n_location,
249 	    o->n_config_file, o->n_config_line);
250 
251 	TAILQ_FOREACH(child, &o->n_children, n_next)
252 		node_duplicate(child, n);
253 
254 	return (n);
255 }
256 
257 static void
258 node_delete(struct node *n)
259 {
260 	struct node *child, *tmp;
261 
262 	assert (n != NULL);
263 
264 	TAILQ_FOREACH_SAFE(child, &n->n_children, n_next, tmp)
265 		node_delete(child);
266 
267 	if (n->n_parent != NULL)
268 		TAILQ_REMOVE(&n->n_parent->n_children, n, n_next);
269 
270 	free(n);
271 }
272 
273 /*
274  * Move (reparent) node 'n' to make it sibling of 'previous', placed
275  * just after it.
276  */
277 static void
278 node_move_after(struct node *n, struct node *previous)
279 {
280 
281 	TAILQ_REMOVE(&n->n_parent->n_children, n, n_next);
282 	n->n_parent = previous->n_parent;
283 	TAILQ_INSERT_AFTER(&previous->n_parent->n_children, previous, n, n_next);
284 }
285 
286 static void
287 node_expand_includes(struct node *root, bool is_master)
288 {
289 	struct node *n, *n2, *tmp, *tmp2, *tmproot;
290 	int error;
291 
292 	TAILQ_FOREACH_SAFE(n, &root->n_children, n_next, tmp) {
293 		if (n->n_key[0] != '+')
294 			continue;
295 
296 		error = access(AUTO_INCLUDE_PATH, F_OK);
297 		if (error != 0) {
298 			log_errx(1, "directory services not configured; "
299 			    "%s does not exist", AUTO_INCLUDE_PATH);
300 		}
301 
302 		/*
303 		 * "+1" to skip leading "+".
304 		 */
305 		yyin = auto_popen(AUTO_INCLUDE_PATH, n->n_key + 1, NULL);
306 		assert(yyin != NULL);
307 
308 		tmproot = node_new_root();
309 		if (is_master)
310 			parse_master_yyin(tmproot, n->n_key);
311 		else
312 			parse_map_yyin(tmproot, n->n_key, NULL);
313 
314 		error = auto_pclose(yyin);
315 		yyin = NULL;
316 		if (error != 0) {
317 			log_errx(1, "failed to handle include \"%s\"",
318 			    n->n_key);
319 		}
320 
321 		/*
322 		 * Entries to be included are now in tmproot.  We need to merge
323 		 * them with the rest, preserving their place and ordering.
324 		 */
325 		TAILQ_FOREACH_REVERSE_SAFE(n2,
326 		    &tmproot->n_children, nodehead, n_next, tmp2) {
327 			node_move_after(n2, n);
328 		}
329 
330 		node_delete(n);
331 		node_delete(tmproot);
332 	}
333 }
334 
335 static char *
336 expand_ampersand(char *string, const char *key)
337 {
338 	char c, *expanded;
339 	int i, ret, before_len = 0;
340 	bool backslashed = false;
341 
342 	assert(key[0] != '\0');
343 
344 	expanded = checked_strdup(string);
345 
346 	for (i = 0; string[i] != '\0'; i++) {
347 		c = string[i];
348 		if (c == '\\' && backslashed == false) {
349 			backslashed = true;
350 			continue;
351 		}
352 		if (backslashed) {
353 			backslashed = false;
354 			continue;
355 		}
356 		backslashed = false;
357 		if (c != '&')
358 			continue;
359 
360 		/*
361 		 * The 'before_len' variable contains the number
362 		 * of characters before the '&'.
363 		 */
364 		before_len = i;
365 		//assert(i < (int)strlen(string));
366 
367 		ret = asprintf(&expanded, "%.*s%s%s",
368 		    before_len, string, key, string + before_len + 1);
369 		if (ret < 0)
370 			log_err(1, "asprintf");
371 
372 		//log_debugx("\"%s\" expanded with key \"%s\" to \"%s\"",
373 		//    string, key, expanded);
374 
375 		/*
376 		 * Figure out where to start searching for next variable.
377 		 */
378 		string = expanded;
379 		i = before_len + strlen(key);
380 		if (i == (int)strlen(string))
381 			break;
382 		backslashed = false;
383 		//assert(i < (int)strlen(string));
384 	}
385 
386 	return (expanded);
387 }
388 
389 /*
390  * Expand "&" in n_location.  If the key is NULL, try to use
391  * key from map entries themselves.  Keep in mind that maps
392  * consist of tho levels of node structures, the key is one
393  * level up.
394  *
395  * Variant with NULL key is for "automount -LL".
396  */
397 void
398 node_expand_ampersand(struct node *n, const char *key)
399 {
400 	struct node *child;
401 
402 	if (n->n_location != NULL) {
403 		if (key == NULL) {
404 			if (n->n_parent != NULL &&
405 			    strcmp(n->n_parent->n_key, "*") != 0) {
406 				n->n_location = expand_ampersand(n->n_location,
407 				    n->n_parent->n_key);
408 			}
409 		} else {
410 			n->n_location = expand_ampersand(n->n_location, key);
411 		}
412 	}
413 
414 	TAILQ_FOREACH(child, &n->n_children, n_next)
415 		node_expand_ampersand(child, key);
416 }
417 
418 /*
419  * Expand "*" in n_key.
420  */
421 void
422 node_expand_wildcard(struct node *n, const char *key)
423 {
424 	struct node *child, *expanded;
425 
426 	assert(key != NULL);
427 
428 	if (strcmp(n->n_key, "*") == 0) {
429 		expanded = node_duplicate(n, NULL);
430 		expanded->n_key = checked_strdup(key);
431 		node_move_after(expanded, n);
432 	}
433 
434 	TAILQ_FOREACH(child, &n->n_children, n_next)
435 		node_expand_wildcard(child, key);
436 }
437 
438 int
439 node_expand_defined(struct node *n)
440 {
441 	struct node *child;
442 	int error, cumulated_error = 0;
443 
444 	if (n->n_location != NULL) {
445 		n->n_location = defined_expand(n->n_location);
446 		if (n->n_location == NULL) {
447 			log_warnx("failed to expand location for %s",
448 			    node_path(n));
449 			return (EINVAL);
450 		}
451 	}
452 
453 	TAILQ_FOREACH(child, &n->n_children, n_next) {
454 		error = node_expand_defined(child);
455 		if (error != 0 && cumulated_error == 0)
456 			cumulated_error = error;
457 	}
458 
459 	return (cumulated_error);
460 }
461 
462 static bool
463 node_is_direct_key(const struct node *n)
464 {
465 
466 	if (n->n_parent != NULL && n->n_parent->n_parent == NULL &&
467 	    strcmp(n->n_key, "/-") == 0) {
468 		return (true);
469 	}
470 
471 	return (false);
472 }
473 
474 bool
475 node_is_direct_map(const struct node *n)
476 {
477 
478 	for (;;) {
479 		assert(n->n_parent != NULL);
480 		if (n->n_parent->n_parent == NULL)
481 			break;
482 		n = n->n_parent;
483 	}
484 
485 	return (node_is_direct_key(n));
486 }
487 
488 bool
489 node_has_wildcards(const struct node *n)
490 {
491 	const struct node *child;
492 
493 	TAILQ_FOREACH(child, &n->n_children, n_next) {
494 		if (strcmp(child->n_key, "*") == 0)
495 			return (true);
496 	}
497 
498 	return (false);
499 }
500 
501 static void
502 node_expand_maps(struct node *n, bool indirect)
503 {
504 	struct node *child, *tmp;
505 
506 	TAILQ_FOREACH_SAFE(child, &n->n_children, n_next, tmp) {
507 		if (node_is_direct_map(child)) {
508 			if (indirect)
509 				continue;
510 		} else {
511 			if (indirect == false)
512 				continue;
513 		}
514 
515 		/*
516 		 * This is the first-level map node; the one that contains
517 		 * the key and subnodes with mountpoints and actual map names.
518 		 */
519 		if (child->n_map == NULL)
520 			continue;
521 
522 		if (indirect) {
523 			log_debugx("map \"%s\" is an indirect map, parsing",
524 			    child->n_map);
525 		} else {
526 			log_debugx("map \"%s\" is a direct map, parsing",
527 			    child->n_map);
528 		}
529 		parse_map(child, child->n_map, NULL, NULL);
530 	}
531 }
532 
533 static void
534 node_expand_direct_maps(struct node *n)
535 {
536 
537 	node_expand_maps(n, false);
538 }
539 
540 void
541 node_expand_indirect_maps(struct node *n)
542 {
543 
544 	node_expand_maps(n, true);
545 }
546 
547 static char *
548 node_path_x(const struct node *n, char *x)
549 {
550 	char *path;
551 
552 	if (n->n_parent == NULL)
553 		return (x);
554 
555 	/*
556 	 * Return "/-" for direct maps only if we were asked for path
557 	 * to the "/-" node itself, not to any of its subnodes.
558 	 */
559 	if (node_is_direct_key(n) && x[0] != '\0')
560 		return (x);
561 
562 	assert(n->n_key[0] != '\0');
563 	path = concat(n->n_key, '/', x);
564 	free(x);
565 
566 	return (node_path_x(n->n_parent, path));
567 }
568 
569 /*
570  * Return full path for node, consisting of concatenated
571  * paths of node itself and all its parents, up to the root.
572  */
573 char *
574 node_path(const struct node *n)
575 {
576 	char *path;
577 	size_t len;
578 
579 	path = node_path_x(n, checked_strdup(""));
580 
581 	/*
582 	 * Strip trailing slash, unless the whole path is "/".
583 	 */
584 	len = strlen(path);
585 	if (len > 1 && path[len - 1] == '/')
586 		path[len - 1] = '\0';
587 
588 	return (path);
589 }
590 
591 static char *
592 node_options_x(const struct node *n, char *x)
593 {
594 	char *options;
595 
596 	if (n == NULL)
597 		return (x);
598 
599 	options = concat(x, ',', n->n_options);
600 	free(x);
601 
602 	return (node_options_x(n->n_parent, options));
603 }
604 
605 /*
606  * Return options for node, consisting of concatenated
607  * options from the node itself and all its parents,
608  * up to the root.
609  */
610 char *
611 node_options(const struct node *n)
612 {
613 
614 	return (node_options_x(n, checked_strdup("")));
615 }
616 
617 static void
618 node_print_indent(const struct node *n, const char *cmdline_options,
619     int indent)
620 {
621 	const struct node *child, *first_child;
622 	char *path, *options, *tmp;
623 
624 	path = node_path(n);
625 	tmp = node_options(n);
626 	options = concat(cmdline_options, ',', tmp);
627 	free(tmp);
628 
629 	/*
630 	 * Do not show both parent and child node if they have the same
631 	 * mountpoint; only show the child node.  This means the typical,
632 	 * "key location", map entries are shown in a single line;
633 	 * the "key mountpoint1 location2 mountpoint2 location2" entries
634 	 * take multiple lines.
635 	 */
636 	first_child = TAILQ_FIRST(&n->n_children);
637 	if (first_child == NULL || TAILQ_NEXT(first_child, n_next) != NULL ||
638 	    strcmp(path, node_path(first_child)) != 0) {
639 		assert(n->n_location == NULL || n->n_map == NULL);
640 		printf("%*.s%-*s %s%-*s %-*s # %s map %s at %s:%d\n",
641 		    indent, "",
642 		    25 - indent,
643 		    path,
644 		    options[0] != '\0' ? "-" : " ",
645 		    20,
646 		    options[0] != '\0' ? options : "",
647 		    20,
648 		    n->n_location != NULL ? n->n_location : n->n_map != NULL ? n->n_map : "",
649 		    node_is_direct_map(n) ? "direct" : "indirect",
650 		    indent == 0 ? "referenced" : "defined",
651 		    n->n_config_file, n->n_config_line);
652 	}
653 
654 	free(path);
655 	free(options);
656 
657 	TAILQ_FOREACH(child, &n->n_children, n_next)
658 		node_print_indent(child, cmdline_options, indent + 2);
659 }
660 
661 /*
662  * Recursively print node with all its children.  The cmdline_options
663  * argument is used for additional options to be prepended to all the
664  * others - usually those are the options passed by command line.
665  */
666 void
667 node_print(const struct node *n, const char *cmdline_options)
668 {
669 	const struct node *child;
670 
671 	TAILQ_FOREACH(child, &n->n_children, n_next)
672 		node_print_indent(child, cmdline_options, 0);
673 }
674 
675 static struct node *
676 node_find_x(struct node *node, const char *path)
677 {
678 	struct node *child, *found;
679 	char *tmp;
680 	size_t tmplen;
681 
682 	//log_debugx("looking up %s in %s", path, node_path(node));
683 
684 	if (!node_is_direct_key(node)) {
685 		tmp = node_path(node);
686 		tmplen = strlen(tmp);
687 		if (strncmp(tmp, path, tmplen) != 0) {
688 			free(tmp);
689 			return (NULL);
690 		}
691 		if (path[tmplen] != '/' && path[tmplen] != '\0') {
692 			/*
693 			 * If we have two map entries like 'foo' and 'foobar', make
694 			 * sure the search for 'foobar' won't match 'foo' instead.
695 			 */
696 			free(tmp);
697 			return (NULL);
698 		}
699 		free(tmp);
700 	}
701 
702 	TAILQ_FOREACH(child, &node->n_children, n_next) {
703 		found = node_find_x(child, path);
704 		if (found != NULL)
705 			return (found);
706 	}
707 
708 	if (node->n_parent == NULL || node_is_direct_key(node))
709 		return (NULL);
710 
711 	return (node);
712 }
713 
714 struct node *
715 node_find(struct node *root, const char *path)
716 {
717 	struct node *node;
718 
719 	assert(root->n_parent == NULL);
720 
721 	node = node_find_x(root, path);
722 	if (node != NULL)
723 		assert(node != root);
724 
725 	return (node);
726 }
727 
728 /*
729  * Canonical form of a map entry looks like this:
730  *
731  * key [-options] [ [/mountpoint] [-options2] location ... ]
732  *
733  * Entries for executable maps are slightly different, as they
734  * lack the 'key' field and are always single-line; the key field
735  * for those maps is taken from 'executable_key' argument.
736  *
737  * We parse it in such a way that a map always has two levels - first
738  * for key, and the second, for the mountpoint.
739  */
740 static void
741 parse_map_yyin(struct node *parent, const char *map, const char *executable_key)
742 {
743 	char *key = NULL, *options = NULL, *mountpoint = NULL,
744 	    *options2 = NULL, *location = NULL;
745 	int ret;
746 	struct node *node;
747 
748 	lineno = 1;
749 
750 	if (executable_key != NULL)
751 		key = checked_strdup(executable_key);
752 
753 	for (;;) {
754 		ret = yylex();
755 		if (ret == 0 || ret == NEWLINE) {
756 			/*
757 			 * In case of executable map, the key is always
758 			 * non-NULL, even if the map is empty.  So, make sure
759 			 * we don't fail empty maps here.
760 			 */
761 			if ((key != NULL && executable_key == NULL) ||
762 			    options != NULL) {
763 				log_errx(1, "truncated entry at %s, line %d",
764 				    map, lineno);
765 			}
766 			if (ret == 0 || executable_key != NULL) {
767 				/*
768 				 * End of file.
769 				 */
770 				break;
771 			} else {
772 				key = options = NULL;
773 				continue;
774 			}
775 		}
776 		if (key == NULL) {
777 			key = checked_strdup(yytext);
778 			if (key[0] == '+') {
779 				node_new(parent, key, NULL, NULL, map, lineno);
780 				key = options = NULL;
781 				continue;
782 			}
783 			continue;
784 		} else if (yytext[0] == '-') {
785 			if (options != NULL) {
786 				log_errx(1, "duplicated options at %s, line %d",
787 				    map, lineno);
788 			}
789 			/*
790 			 * +1 to skip leading "-".
791 			 */
792 			options = checked_strdup(yytext + 1);
793 			continue;
794 		}
795 
796 		/*
797 		 * We cannot properly handle a situation where the map key
798 		 * is "/".  Ignore such entries.
799 		 *
800 		 * XXX: According to Piete Brooks, Linux automounter uses
801 		 *	"/" as a wildcard character in LDAP maps.  Perhaps
802 		 *	we should work around this braindamage by substituting
803 		 *	"*" for "/"?
804 		 */
805 		if (strcmp(key, "/") == 0) {
806 			log_warnx("nonsensical map key \"/\" at %s, line %d; "
807 			    "ignoring map entry ", map, lineno);
808 
809 			/*
810 			 * Skip the rest of the entry.
811 			 */
812 			do {
813 				ret = yylex();
814 			} while (ret != 0 && ret != NEWLINE);
815 
816 			key = options = NULL;
817 			continue;
818 		}
819 
820 		//log_debugx("adding map node, %s", key);
821 		node = node_new(parent, key, options, NULL, map, lineno);
822 		key = options = NULL;
823 
824 		for (;;) {
825 			if (yytext[0] == '/') {
826 				if (mountpoint != NULL) {
827 					log_errx(1, "duplicated mountpoint "
828 					    "in %s, line %d", map, lineno);
829 				}
830 				if (options2 != NULL || location != NULL) {
831 					log_errx(1, "mountpoint out of order "
832 					    "in %s, line %d", map, lineno);
833 				}
834 				mountpoint = checked_strdup(yytext);
835 				goto again;
836 			}
837 
838 			if (yytext[0] == '-') {
839 				if (options2 != NULL) {
840 					log_errx(1, "duplicated options "
841 					    "in %s, line %d", map, lineno);
842 				}
843 				if (location != NULL) {
844 					log_errx(1, "options out of order "
845 					    "in %s, line %d", map, lineno);
846 				}
847 				options2 = checked_strdup(yytext + 1);
848 				goto again;
849 			}
850 
851 			if (location != NULL) {
852 				log_errx(1, "too many arguments "
853 				    "in %s, line %d", map, lineno);
854 			}
855 
856 			/*
857 			 * If location field starts with colon, e.g. ":/dev/cd0",
858 			 * then strip it.
859 			 */
860 			if (yytext[0] == ':') {
861 				location = checked_strdup(yytext + 1);
862 				if (location[0] == '\0') {
863 					log_errx(1, "empty location in %s, "
864 					    "line %d", map, lineno);
865 				}
866 			} else {
867 				location = checked_strdup(yytext);
868 			}
869 
870 			if (mountpoint == NULL)
871 				mountpoint = checked_strdup("/");
872 			if (options2 == NULL)
873 				options2 = checked_strdup("");
874 
875 #if 0
876 			log_debugx("adding map node, %s %s %s",
877 			    mountpoint, options2, location);
878 #endif
879 			node_new(node, mountpoint, options2, location,
880 			    map, lineno);
881 			mountpoint = options2 = location = NULL;
882 again:
883 			ret = yylex();
884 			if (ret == 0 || ret == NEWLINE) {
885 				if (mountpoint != NULL || options2 != NULL ||
886 				    location != NULL) {
887 					log_errx(1, "truncated entry "
888 					    "in %s, line %d", map, lineno);
889 				}
890 				break;
891 			}
892 		}
893 	}
894 }
895 
896 /*
897  * Parse output of a special map called without argument.  It is a list
898  * of keys, separated by newlines.  They can contain whitespace, so use
899  * getline(3) instead of lexer used for maps.
900  */
901 static void
902 parse_map_keys_yyin(struct node *parent, const char *map)
903 {
904 	char *line = NULL, *key;
905 	size_t linecap = 0;
906 	ssize_t linelen;
907 
908 	lineno = 1;
909 
910 	for (;;) {
911 		linelen = getline(&line, &linecap, yyin);
912 		if (linelen < 0) {
913 			/*
914 			 * End of file.
915 			 */
916 			break;
917 		}
918 		if (linelen <= 1) {
919 			/*
920 			 * Empty line, consisting of just the newline.
921 			 */
922 			continue;
923 		}
924 
925 		/*
926 		 * "-1" to strip the trailing newline.
927 		 */
928 		key = strndup(line, linelen - 1);
929 
930 		log_debugx("adding key \"%s\"", key);
931 		node_new(parent, key, NULL, NULL, map, lineno);
932 		lineno++;
933 	}
934 	free(line);
935 }
936 
937 static bool
938 file_is_executable(const char *path)
939 {
940 	struct stat sb;
941 	int error;
942 
943 	error = stat(path, &sb);
944 	if (error != 0)
945 		log_err(1, "cannot stat %s", path);
946 	if ((sb.st_mode & S_IXUSR) || (sb.st_mode & S_IXGRP) ||
947 	    (sb.st_mode & S_IXOTH))
948 		return (true);
949 	return (false);
950 }
951 
952 /*
953  * Parse a special map, e.g. "-hosts".
954  */
955 static void
956 parse_special_map(struct node *parent, const char *map, const char *key)
957 {
958 	char *path;
959 	int error, ret;
960 
961 	assert(map[0] == '-');
962 
963 	/*
964 	 * +1 to skip leading "-" in map name.
965 	 */
966 	ret = asprintf(&path, "%s/special_%s", AUTO_SPECIAL_PREFIX, map + 1);
967 	if (ret < 0)
968 		log_err(1, "asprintf");
969 
970 	yyin = auto_popen(path, key, NULL);
971 	assert(yyin != NULL);
972 
973 	if (key == NULL) {
974 		parse_map_keys_yyin(parent, map);
975 	} else {
976 		parse_map_yyin(parent, map, key);
977 	}
978 
979 	error = auto_pclose(yyin);
980 	yyin = NULL;
981 	if (error != 0)
982 		log_errx(1, "failed to handle special map \"%s\"", map);
983 
984 	node_expand_includes(parent, false);
985 	node_expand_direct_maps(parent);
986 
987 	free(path);
988 }
989 
990 /*
991  * Retrieve and parse map from directory services, e.g. LDAP.
992  * Note that it is different from executable maps, in that
993  * the include script outputs the whole map to standard output
994  * (as opposed to executable maps that only output a single
995  * entry, without the key), and it takes the map name as an
996  * argument, instead of key.
997  */
998 static void
999 parse_included_map(struct node *parent, const char *map)
1000 {
1001 	int error;
1002 
1003 	assert(map[0] != '-');
1004 	assert(map[0] != '/');
1005 
1006 	error = access(AUTO_INCLUDE_PATH, F_OK);
1007 	if (error != 0) {
1008 		log_errx(1, "directory services not configured;"
1009 		    " %s does not exist", AUTO_INCLUDE_PATH);
1010 	}
1011 
1012 	yyin = auto_popen(AUTO_INCLUDE_PATH, map, NULL);
1013 	assert(yyin != NULL);
1014 
1015 	parse_map_yyin(parent, map, NULL);
1016 
1017 	error = auto_pclose(yyin);
1018 	yyin = NULL;
1019 	if (error != 0)
1020 		log_errx(1, "failed to handle remote map \"%s\"", map);
1021 
1022 	node_expand_includes(parent, false);
1023 	node_expand_direct_maps(parent);
1024 }
1025 
1026 void
1027 parse_map(struct node *parent, const char *map, const char *key,
1028     bool *wildcards)
1029 {
1030 	char *path = NULL;
1031 	int error, ret;
1032 	bool executable;
1033 
1034 	assert(map != NULL);
1035 	assert(map[0] != '\0');
1036 
1037 	log_debugx("parsing map \"%s\"", map);
1038 
1039 	if (wildcards != NULL)
1040 		*wildcards = false;
1041 
1042 	if (map[0] == '-') {
1043 		if (wildcards != NULL)
1044 			*wildcards = true;
1045 		return (parse_special_map(parent, map, key));
1046 	}
1047 
1048 	if (map[0] == '/') {
1049 		path = checked_strdup(map);
1050 	} else {
1051 		ret = asprintf(&path, "%s/%s", AUTO_MAP_PREFIX, map);
1052 		if (ret < 0)
1053 			log_err(1, "asprintf");
1054 		log_debugx("map \"%s\" maps to \"%s\"", map, path);
1055 
1056 		/*
1057 		 * See if the file exists.  If not, try to obtain the map
1058 		 * from directory services.
1059 		 */
1060 		error = access(path, F_OK);
1061 		if (error != 0) {
1062 			log_debugx("map file \"%s\" does not exist; falling "
1063 			    "back to directory services", path);
1064 			return (parse_included_map(parent, map));
1065 		}
1066 	}
1067 
1068 	executable = file_is_executable(path);
1069 
1070 	if (executable) {
1071 		log_debugx("map \"%s\" is executable", map);
1072 
1073 		if (wildcards != NULL)
1074 			*wildcards = true;
1075 
1076 		if (key != NULL) {
1077 			yyin = auto_popen(path, key, NULL);
1078 		} else {
1079 			yyin = auto_popen(path, NULL);
1080 		}
1081 		assert(yyin != NULL);
1082 	} else {
1083 		yyin = fopen(path, "r");
1084 		if (yyin == NULL)
1085 			log_err(1, "unable to open \"%s\"", path);
1086 	}
1087 
1088 	free(path);
1089 	path = NULL;
1090 
1091 	parse_map_yyin(parent, map, executable ? key : NULL);
1092 
1093 	if (executable) {
1094 		error = auto_pclose(yyin);
1095 		yyin = NULL;
1096 		if (error != 0) {
1097 			log_errx(1, "failed to handle executable map \"%s\"",
1098 			    map);
1099 		}
1100 	} else {
1101 		fclose(yyin);
1102 	}
1103 	yyin = NULL;
1104 
1105 	log_debugx("done parsing map \"%s\"", map);
1106 
1107 	node_expand_includes(parent, false);
1108 	node_expand_direct_maps(parent);
1109 }
1110 
1111 static void
1112 parse_master_yyin(struct node *root, const char *master)
1113 {
1114 	char *mountpoint = NULL, *map = NULL, *options = NULL;
1115 	int ret;
1116 
1117 	/*
1118 	 * XXX: 1 gives incorrect values; wtf?
1119 	 */
1120 	lineno = 0;
1121 
1122 	for (;;) {
1123 		ret = yylex();
1124 		if (ret == 0 || ret == NEWLINE) {
1125 			if (mountpoint != NULL) {
1126 				//log_debugx("adding map for %s", mountpoint);
1127 				node_new_map(root, mountpoint, options, map,
1128 				    master, lineno);
1129 			}
1130 			if (ret == 0) {
1131 				break;
1132 			} else {
1133 				mountpoint = map = options = NULL;
1134 				continue;
1135 			}
1136 		}
1137 		if (mountpoint == NULL) {
1138 			mountpoint = checked_strdup(yytext);
1139 		} else if (map == NULL) {
1140 			map = checked_strdup(yytext);
1141 		} else if (options == NULL) {
1142 			/*
1143 			 * +1 to skip leading "-".
1144 			 */
1145 			options = checked_strdup(yytext + 1);
1146 		} else {
1147 			log_errx(1, "too many arguments at %s, line %d",
1148 			    master, lineno);
1149 		}
1150 	}
1151 }
1152 
1153 void
1154 parse_master(struct node *root, const char *master)
1155 {
1156 
1157 	log_debugx("parsing auto_master file at \"%s\"", master);
1158 
1159 	yyin = fopen(master, "r");
1160 	if (yyin == NULL)
1161 		err(1, "unable to open %s", master);
1162 
1163 	parse_master_yyin(root, master);
1164 
1165 	fclose(yyin);
1166 	yyin = NULL;
1167 
1168 	log_debugx("done parsing \"%s\"", master);
1169 
1170 	node_expand_includes(root, true);
1171 	node_expand_direct_maps(root);
1172 }
1173 
1174 /*
1175  * Two things daemon(3) does, that we actually also want to do
1176  * when running in foreground, is closing the stdin and chdiring
1177  * to "/".  This is what we do here.
1178  */
1179 void
1180 lesser_daemon(void)
1181 {
1182 	int error, fd;
1183 
1184 	error = chdir("/");
1185 	if (error != 0)
1186 		log_warn("chdir");
1187 
1188 	fd = open(_PATH_DEVNULL, O_RDWR, 0);
1189 	if (fd < 0) {
1190 		log_warn("cannot open %s", _PATH_DEVNULL);
1191 		return;
1192 	}
1193 
1194 	error = dup2(fd, STDIN_FILENO);
1195 	if (error != 0)
1196 		log_warn("dup2");
1197 
1198 	error = close(fd);
1199 	if (error != 0) {
1200 		/* Bloody hell. */
1201 		log_warn("close");
1202 	}
1203 }
1204 
1205 /*
1206  * Applicable to NFSv3 only, see rpc.umntall(8).
1207  */
1208 void
1209 rpc_umntall(void)
1210 {
1211 	FILE *f;
1212 
1213 	f = auto_popen("rpc.umntall", "-k", NULL);
1214 	assert(f != NULL);
1215 	auto_pclose(f);
1216 }
1217 
1218 int
1219 main(int argc, char **argv)
1220 {
1221 	char *cmdname;
1222 
1223 	if (argv[0] == NULL)
1224 		log_errx(1, "NULL command name");
1225 
1226 	cmdname = basename(argv[0]);
1227 
1228 	if (strcmp(cmdname, "automount") == 0)
1229 		return (main_automount(argc, argv));
1230 	else if (strcmp(cmdname, "automountd") == 0)
1231 		return (main_automountd(argc, argv));
1232 	else if (strcmp(cmdname, "autounmountd") == 0)
1233 		return (main_autounmountd(argc, argv));
1234 	else
1235 		log_errx(1, "binary name should be either \"automount\", "
1236 		    "\"automountd\", or \"autounmountd\"");
1237 }
1238