xref: /freebsd/usr.sbin/autofs/common.c (revision 3416500aef140042c64bc149cb1ec6620483bc44)
1 /*-
2  * Copyright (c) 2014 The FreeBSD Foundation
3  * All rights reserved.
4  *
5  * This software was developed by Edward Tomasz Napierala under sponsorship
6  * from the FreeBSD Foundation.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  */
30 
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
33 
34 #include <sys/types.h>
35 #include <sys/time.h>
36 #include <sys/ioctl.h>
37 #include <sys/param.h>
38 #include <sys/linker.h>
39 #include <sys/mount.h>
40 #include <sys/socket.h>
41 #include <sys/stat.h>
42 #include <sys/wait.h>
43 #include <sys/utsname.h>
44 #include <assert.h>
45 #include <ctype.h>
46 #include <err.h>
47 #include <errno.h>
48 #include <fcntl.h>
49 #include <libgen.h>
50 #include <libutil.h>
51 #include <netdb.h>
52 #include <paths.h>
53 #include <signal.h>
54 #include <stdbool.h>
55 #include <stdint.h>
56 #include <stdio.h>
57 #include <stdlib.h>
58 #include <string.h>
59 #include <unistd.h>
60 
61 #include "autofs_ioctl.h"
62 
63 #include "common.h"
64 
65 extern FILE *yyin;
66 extern char *yytext;
67 extern int yylex(void);
68 
69 static void	parse_master_yyin(struct node *root, const char *master);
70 static void	parse_map_yyin(struct node *parent, const char *map,
71 		    const char *executable_key);
72 
73 char *
74 checked_strdup(const char *s)
75 {
76 	char *c;
77 
78 	assert(s != NULL);
79 
80 	c = strdup(s);
81 	if (c == NULL)
82 		log_err(1, "strdup");
83 	return (c);
84 }
85 
86 /*
87  * Concatenate two strings, inserting separator between them, unless not needed.
88  */
89 char *
90 concat(const char *s1, char separator, const char *s2)
91 {
92 	char *result;
93 	char s1last, s2first;
94 	int ret;
95 
96 	if (s1 == NULL)
97 		s1 = "";
98 	if (s2 == NULL)
99 		s2 = "";
100 
101 	if (s1[0] == '\0')
102 		s1last = '\0';
103 	else
104 		s1last = s1[strlen(s1) - 1];
105 
106 	s2first = s2[0];
107 
108 	if (s1last == separator && s2first == separator) {
109 		/*
110 		 * If s1 ends with the separator and s2 begins with
111 		 * it - skip the latter; otherwise concatenating "/"
112 		 * and "/foo" would end up returning "//foo".
113 		 */
114 		ret = asprintf(&result, "%s%s", s1, s2 + 1);
115 	} else if (s1last == separator || s2first == separator ||
116 	    s1[0] == '\0' || s2[0] == '\0') {
117 		ret = asprintf(&result, "%s%s", s1, s2);
118 	} else {
119 		ret = asprintf(&result, "%s%c%s", s1, separator, s2);
120 	}
121 	if (ret < 0)
122 		log_err(1, "asprintf");
123 
124 	//log_debugx("%s: got %s and %s, returning %s", __func__, s1, s2, result);
125 
126 	return (result);
127 }
128 
129 void
130 create_directory(const char *path)
131 {
132 	char *component, *copy, *tofree, *partial, *tmp;
133 	int error;
134 
135 	assert(path[0] == '/');
136 
137 	/*
138 	 * +1 to skip the leading slash.
139 	 */
140 	copy = tofree = checked_strdup(path + 1);
141 
142 	partial = checked_strdup("");
143 	for (;;) {
144 		component = strsep(&copy, "/");
145 		if (component == NULL)
146 			break;
147 		tmp = concat(partial, '/', component);
148 		free(partial);
149 		partial = tmp;
150 		//log_debugx("creating \"%s\"", partial);
151 		error = mkdir(partial, 0755);
152 		if (error != 0 && errno != EEXIST) {
153 			log_warn("cannot create %s", partial);
154 			return;
155 		}
156 	}
157 
158 	free(tofree);
159 }
160 
161 struct node *
162 node_new_root(void)
163 {
164 	struct node *n;
165 
166 	n = calloc(1, sizeof(*n));
167 	if (n == NULL)
168 		log_err(1, "calloc");
169 	// XXX
170 	n->n_key = checked_strdup("/");
171 	n->n_options = checked_strdup("");
172 
173 	TAILQ_INIT(&n->n_children);
174 
175 	return (n);
176 }
177 
178 struct node *
179 node_new(struct node *parent, char *key, char *options, char *location,
180     const char *config_file, int config_line)
181 {
182 	struct node *n;
183 
184 	n = calloc(1, sizeof(*n));
185 	if (n == NULL)
186 		log_err(1, "calloc");
187 
188 	TAILQ_INIT(&n->n_children);
189 	assert(key != NULL);
190 	assert(key[0] != '\0');
191 	n->n_key = key;
192 	if (options != NULL)
193 		n->n_options = options;
194 	else
195 		n->n_options = strdup("");
196 	n->n_location = location;
197 	assert(config_file != NULL);
198 	n->n_config_file = config_file;
199 	assert(config_line >= 0);
200 	n->n_config_line = config_line;
201 
202 	assert(parent != NULL);
203 	n->n_parent = parent;
204 	TAILQ_INSERT_TAIL(&parent->n_children, n, n_next);
205 
206 	return (n);
207 }
208 
209 struct node *
210 node_new_map(struct node *parent, char *key, char *options, char *map,
211     const char *config_file, int config_line)
212 {
213 	struct node *n;
214 
215 	n = calloc(1, sizeof(*n));
216 	if (n == NULL)
217 		log_err(1, "calloc");
218 
219 	TAILQ_INIT(&n->n_children);
220 	assert(key != NULL);
221 	assert(key[0] != '\0');
222 	n->n_key = key;
223 	if (options != NULL)
224 		n->n_options = options;
225 	else
226 		n->n_options = strdup("");
227 	n->n_map = map;
228 	assert(config_file != NULL);
229 	n->n_config_file = config_file;
230 	assert(config_line >= 0);
231 	n->n_config_line = config_line;
232 
233 	assert(parent != NULL);
234 	n->n_parent = parent;
235 	TAILQ_INSERT_TAIL(&parent->n_children, n, n_next);
236 
237 	return (n);
238 }
239 
240 static struct node *
241 node_duplicate(const struct node *o, struct node *parent)
242 {
243 	const struct node *child;
244 	struct node *n;
245 
246 	if (parent == NULL)
247 		parent = o->n_parent;
248 
249 	n = node_new(parent, o->n_key, o->n_options, o->n_location,
250 	    o->n_config_file, o->n_config_line);
251 
252 	TAILQ_FOREACH(child, &o->n_children, n_next)
253 		node_duplicate(child, n);
254 
255 	return (n);
256 }
257 
258 static void
259 node_delete(struct node *n)
260 {
261 	struct node *child, *tmp;
262 
263 	assert (n != NULL);
264 
265 	TAILQ_FOREACH_SAFE(child, &n->n_children, n_next, tmp)
266 		node_delete(child);
267 
268 	if (n->n_parent != NULL)
269 		TAILQ_REMOVE(&n->n_parent->n_children, n, n_next);
270 
271 	free(n);
272 }
273 
274 /*
275  * Move (reparent) node 'n' to make it sibling of 'previous', placed
276  * just after it.
277  */
278 static void
279 node_move_after(struct node *n, struct node *previous)
280 {
281 
282 	TAILQ_REMOVE(&n->n_parent->n_children, n, n_next);
283 	n->n_parent = previous->n_parent;
284 	TAILQ_INSERT_AFTER(&previous->n_parent->n_children, previous, n, n_next);
285 }
286 
287 static void
288 node_expand_includes(struct node *root, bool is_master)
289 {
290 	struct node *n, *n2, *tmp, *tmp2, *tmproot;
291 	int error;
292 
293 	TAILQ_FOREACH_SAFE(n, &root->n_children, n_next, tmp) {
294 		if (n->n_key[0] != '+')
295 			continue;
296 
297 		error = access(AUTO_INCLUDE_PATH, F_OK);
298 		if (error != 0) {
299 			log_errx(1, "directory services not configured; "
300 			    "%s does not exist", AUTO_INCLUDE_PATH);
301 		}
302 
303 		/*
304 		 * "+1" to skip leading "+".
305 		 */
306 		yyin = auto_popen(AUTO_INCLUDE_PATH, n->n_key + 1, NULL);
307 		assert(yyin != NULL);
308 
309 		tmproot = node_new_root();
310 		if (is_master)
311 			parse_master_yyin(tmproot, n->n_key);
312 		else
313 			parse_map_yyin(tmproot, n->n_key, NULL);
314 
315 		error = auto_pclose(yyin);
316 		yyin = NULL;
317 		if (error != 0) {
318 			log_errx(1, "failed to handle include \"%s\"",
319 			    n->n_key);
320 		}
321 
322 		/*
323 		 * Entries to be included are now in tmproot.  We need to merge
324 		 * them with the rest, preserving their place and ordering.
325 		 */
326 		TAILQ_FOREACH_REVERSE_SAFE(n2,
327 		    &tmproot->n_children, nodehead, n_next, tmp2) {
328 			node_move_after(n2, n);
329 		}
330 
331 		node_delete(n);
332 		node_delete(tmproot);
333 	}
334 }
335 
336 static char *
337 expand_ampersand(char *string, const char *key)
338 {
339 	char c, *expanded;
340 	int i, ret, before_len = 0;
341 	bool backslashed = false;
342 
343 	assert(key[0] != '\0');
344 
345 	expanded = checked_strdup(string);
346 
347 	for (i = 0; string[i] != '\0'; i++) {
348 		c = string[i];
349 		if (c == '\\' && backslashed == false) {
350 			backslashed = true;
351 			continue;
352 		}
353 		if (backslashed) {
354 			backslashed = false;
355 			continue;
356 		}
357 		backslashed = false;
358 		if (c != '&')
359 			continue;
360 
361 		/*
362 		 * The 'before_len' variable contains the number
363 		 * of characters before the '&'.
364 		 */
365 		before_len = i;
366 		//assert(i + 1 < (int)strlen(string));
367 
368 		ret = asprintf(&expanded, "%.*s%s%s",
369 		    before_len, string, key, string + before_len + 1);
370 		if (ret < 0)
371 			log_err(1, "asprintf");
372 
373 		//log_debugx("\"%s\" expanded with key \"%s\" to \"%s\"",
374 		//    string, key, expanded);
375 
376 		/*
377 		 * Figure out where to start searching for next variable.
378 		 */
379 		string = expanded;
380 		i = before_len + strlen(key);
381 		backslashed = false;
382 		//assert(i < (int)strlen(string));
383 	}
384 
385 	return (expanded);
386 }
387 
388 /*
389  * Expand "&" in n_location.  If the key is NULL, try to use
390  * key from map entries themselves.  Keep in mind that maps
391  * consist of tho levels of node structures, the key is one
392  * level up.
393  *
394  * Variant with NULL key is for "automount -LL".
395  */
396 void
397 node_expand_ampersand(struct node *n, const char *key)
398 {
399 	struct node *child;
400 
401 	if (n->n_location != NULL) {
402 		if (key == NULL) {
403 			if (n->n_parent != NULL &&
404 			    strcmp(n->n_parent->n_key, "*") != 0) {
405 				n->n_location = expand_ampersand(n->n_location,
406 				    n->n_parent->n_key);
407 			}
408 		} else {
409 			n->n_location = expand_ampersand(n->n_location, key);
410 		}
411 	}
412 
413 	TAILQ_FOREACH(child, &n->n_children, n_next)
414 		node_expand_ampersand(child, key);
415 }
416 
417 /*
418  * Expand "*" in n_key.
419  */
420 void
421 node_expand_wildcard(struct node *n, const char *key)
422 {
423 	struct node *child, *expanded;
424 
425 	assert(key != NULL);
426 
427 	if (strcmp(n->n_key, "*") == 0) {
428 		expanded = node_duplicate(n, NULL);
429 		expanded->n_key = checked_strdup(key);
430 		node_move_after(expanded, n);
431 	}
432 
433 	TAILQ_FOREACH(child, &n->n_children, n_next)
434 		node_expand_wildcard(child, key);
435 }
436 
437 int
438 node_expand_defined(struct node *n)
439 {
440 	struct node *child;
441 	int error, cumulated_error = 0;
442 
443 	if (n->n_location != NULL) {
444 		n->n_location = defined_expand(n->n_location);
445 		if (n->n_location == NULL) {
446 			log_warnx("failed to expand location for %s",
447 			    node_path(n));
448 			return (EINVAL);
449 		}
450 	}
451 
452 	TAILQ_FOREACH(child, &n->n_children, n_next) {
453 		error = node_expand_defined(child);
454 		if (error != 0 && cumulated_error == 0)
455 			cumulated_error = error;
456 	}
457 
458 	return (cumulated_error);
459 }
460 
461 static bool
462 node_is_direct_key(const struct node *n)
463 {
464 
465 	if (n->n_parent != NULL && n->n_parent->n_parent == NULL &&
466 	    strcmp(n->n_key, "/-") == 0) {
467 		return (true);
468 	}
469 
470 	return (false);
471 }
472 
473 bool
474 node_is_direct_map(const struct node *n)
475 {
476 
477 	for (;;) {
478 		assert(n->n_parent != NULL);
479 		if (n->n_parent->n_parent == NULL)
480 			break;
481 		n = n->n_parent;
482 	}
483 
484 	return (node_is_direct_key(n));
485 }
486 
487 bool
488 node_has_wildcards(const struct node *n)
489 {
490 	const struct node *child;
491 
492 	TAILQ_FOREACH(child, &n->n_children, n_next) {
493 		if (strcmp(child->n_key, "*") == 0)
494 			return (true);
495 	}
496 
497 	return (false);
498 }
499 
500 static void
501 node_expand_maps(struct node *n, bool indirect)
502 {
503 	struct node *child, *tmp;
504 
505 	TAILQ_FOREACH_SAFE(child, &n->n_children, n_next, tmp) {
506 		if (node_is_direct_map(child)) {
507 			if (indirect)
508 				continue;
509 		} else {
510 			if (indirect == false)
511 				continue;
512 		}
513 
514 		/*
515 		 * This is the first-level map node; the one that contains
516 		 * the key and subnodes with mountpoints and actual map names.
517 		 */
518 		if (child->n_map == NULL)
519 			continue;
520 
521 		if (indirect) {
522 			log_debugx("map \"%s\" is an indirect map, parsing",
523 			    child->n_map);
524 		} else {
525 			log_debugx("map \"%s\" is a direct map, parsing",
526 			    child->n_map);
527 		}
528 		parse_map(child, child->n_map, NULL, NULL);
529 	}
530 }
531 
532 static void
533 node_expand_direct_maps(struct node *n)
534 {
535 
536 	node_expand_maps(n, false);
537 }
538 
539 void
540 node_expand_indirect_maps(struct node *n)
541 {
542 
543 	node_expand_maps(n, true);
544 }
545 
546 static char *
547 node_path_x(const struct node *n, char *x)
548 {
549 	char *path;
550 
551 	if (n->n_parent == NULL)
552 		return (x);
553 
554 	/*
555 	 * Return "/-" for direct maps only if we were asked for path
556 	 * to the "/-" node itself, not to any of its subnodes.
557 	 */
558 	if (node_is_direct_key(n) && x[0] != '\0')
559 		return (x);
560 
561 	assert(n->n_key[0] != '\0');
562 	path = concat(n->n_key, '/', x);
563 	free(x);
564 
565 	return (node_path_x(n->n_parent, path));
566 }
567 
568 /*
569  * Return full path for node, consisting of concatenated
570  * paths of node itself and all its parents, up to the root.
571  */
572 char *
573 node_path(const struct node *n)
574 {
575 	char *path;
576 	size_t len;
577 
578 	path = node_path_x(n, checked_strdup(""));
579 
580 	/*
581 	 * Strip trailing slash, unless the whole path is "/".
582 	 */
583 	len = strlen(path);
584 	if (len > 1 && path[len - 1] == '/')
585 		path[len - 1] = '\0';
586 
587 	return (path);
588 }
589 
590 static char *
591 node_options_x(const struct node *n, char *x)
592 {
593 	char *options;
594 
595 	if (n == NULL)
596 		return (x);
597 
598 	options = concat(x, ',', n->n_options);
599 	free(x);
600 
601 	return (node_options_x(n->n_parent, options));
602 }
603 
604 /*
605  * Return options for node, consisting of concatenated
606  * options from the node itself and all its parents,
607  * up to the root.
608  */
609 char *
610 node_options(const struct node *n)
611 {
612 
613 	return (node_options_x(n, checked_strdup("")));
614 }
615 
616 static void
617 node_print_indent(const struct node *n, const char *cmdline_options,
618     int indent)
619 {
620 	const struct node *child, *first_child;
621 	char *path, *options, *tmp;
622 
623 	path = node_path(n);
624 	tmp = node_options(n);
625 	options = concat(cmdline_options, ',', tmp);
626 	free(tmp);
627 
628 	/*
629 	 * Do not show both parent and child node if they have the same
630 	 * mountpoint; only show the child node.  This means the typical,
631 	 * "key location", map entries are shown in a single line;
632 	 * the "key mountpoint1 location2 mountpoint2 location2" entries
633 	 * take multiple lines.
634 	 */
635 	first_child = TAILQ_FIRST(&n->n_children);
636 	if (first_child == NULL || TAILQ_NEXT(first_child, n_next) != NULL ||
637 	    strcmp(path, node_path(first_child)) != 0) {
638 		assert(n->n_location == NULL || n->n_map == NULL);
639 		printf("%*.s%-*s %s%-*s %-*s # %s map %s at %s:%d\n",
640 		    indent, "",
641 		    25 - indent,
642 		    path,
643 		    options[0] != '\0' ? "-" : " ",
644 		    20,
645 		    options[0] != '\0' ? options : "",
646 		    20,
647 		    n->n_location != NULL ? n->n_location : n->n_map != NULL ? n->n_map : "",
648 		    node_is_direct_map(n) ? "direct" : "indirect",
649 		    indent == 0 ? "referenced" : "defined",
650 		    n->n_config_file, n->n_config_line);
651 	}
652 
653 	free(path);
654 	free(options);
655 
656 	TAILQ_FOREACH(child, &n->n_children, n_next)
657 		node_print_indent(child, cmdline_options, indent + 2);
658 }
659 
660 /*
661  * Recursively print node with all its children.  The cmdline_options
662  * argument is used for additional options to be prepended to all the
663  * others - usually those are the options passed by command line.
664  */
665 void
666 node_print(const struct node *n, const char *cmdline_options)
667 {
668 	const struct node *child;
669 
670 	TAILQ_FOREACH(child, &n->n_children, n_next)
671 		node_print_indent(child, cmdline_options, 0);
672 }
673 
674 static struct node *
675 node_find_x(struct node *node, const char *path)
676 {
677 	struct node *child, *found;
678 	char *tmp;
679 	size_t tmplen;
680 
681 	//log_debugx("looking up %s in %s", path, node_path(node));
682 
683 	if (!node_is_direct_key(node)) {
684 		tmp = node_path(node);
685 		tmplen = strlen(tmp);
686 		if (strncmp(tmp, path, tmplen) != 0) {
687 			free(tmp);
688 			return (NULL);
689 		}
690 		if (path[tmplen] != '/' && path[tmplen] != '\0') {
691 			/*
692 			 * If we have two map entries like 'foo' and 'foobar', make
693 			 * sure the search for 'foobar' won't match 'foo' instead.
694 			 */
695 			free(tmp);
696 			return (NULL);
697 		}
698 		free(tmp);
699 	}
700 
701 	TAILQ_FOREACH(child, &node->n_children, n_next) {
702 		found = node_find_x(child, path);
703 		if (found != NULL)
704 			return (found);
705 	}
706 
707 	if (node->n_parent == NULL || node_is_direct_key(node))
708 		return (NULL);
709 
710 	return (node);
711 }
712 
713 struct node *
714 node_find(struct node *root, const char *path)
715 {
716 	struct node *node;
717 
718 	assert(root->n_parent == NULL);
719 
720 	node = node_find_x(root, path);
721 	if (node != NULL)
722 		assert(node != root);
723 
724 	return (node);
725 }
726 
727 /*
728  * Canonical form of a map entry looks like this:
729  *
730  * key [-options] [ [/mountpoint] [-options2] location ... ]
731  *
732  * Entries for executable maps are slightly different, as they
733  * lack the 'key' field and are always single-line; the key field
734  * for those maps is taken from 'executable_key' argument.
735  *
736  * We parse it in such a way that a map always has two levels - first
737  * for key, and the second, for the mountpoint.
738  */
739 static void
740 parse_map_yyin(struct node *parent, const char *map, const char *executable_key)
741 {
742 	char *key = NULL, *options = NULL, *mountpoint = NULL,
743 	    *options2 = NULL, *location = NULL;
744 	int ret;
745 	struct node *node;
746 
747 	lineno = 1;
748 
749 	if (executable_key != NULL)
750 		key = checked_strdup(executable_key);
751 
752 	for (;;) {
753 		ret = yylex();
754 		if (ret == 0 || ret == NEWLINE) {
755 			/*
756 			 * In case of executable map, the key is always
757 			 * non-NULL, even if the map is empty.  So, make sure
758 			 * we don't fail empty maps here.
759 			 */
760 			if ((key != NULL && executable_key == NULL) ||
761 			    options != NULL) {
762 				log_errx(1, "truncated entry at %s, line %d",
763 				    map, lineno);
764 			}
765 			if (ret == 0 || executable_key != NULL) {
766 				/*
767 				 * End of file.
768 				 */
769 				break;
770 			} else {
771 				key = options = NULL;
772 				continue;
773 			}
774 		}
775 		if (key == NULL) {
776 			key = checked_strdup(yytext);
777 			if (key[0] == '+') {
778 				node_new(parent, key, NULL, NULL, map, lineno);
779 				key = options = NULL;
780 				continue;
781 			}
782 			continue;
783 		} else if (yytext[0] == '-') {
784 			if (options != NULL) {
785 				log_errx(1, "duplicated options at %s, line %d",
786 				    map, lineno);
787 			}
788 			/*
789 			 * +1 to skip leading "-".
790 			 */
791 			options = checked_strdup(yytext + 1);
792 			continue;
793 		}
794 
795 		/*
796 		 * We cannot properly handle a situation where the map key
797 		 * is "/".  Ignore such entries.
798 		 *
799 		 * XXX: According to Piete Brooks, Linux automounter uses
800 		 *	"/" as a wildcard character in LDAP maps.  Perhaps
801 		 *	we should work around this braindamage by substituting
802 		 *	"*" for "/"?
803 		 */
804 		if (strcmp(key, "/") == 0) {
805 			log_warnx("nonsensical map key \"/\" at %s, line %d; "
806 			    "ignoring map entry ", map, lineno);
807 
808 			/*
809 			 * Skip the rest of the entry.
810 			 */
811 			do {
812 				ret = yylex();
813 			} while (ret != 0 && ret != NEWLINE);
814 
815 			key = options = NULL;
816 			continue;
817 		}
818 
819 		//log_debugx("adding map node, %s", key);
820 		node = node_new(parent, key, options, NULL, map, lineno);
821 		key = options = NULL;
822 
823 		for (;;) {
824 			if (yytext[0] == '/') {
825 				if (mountpoint != NULL) {
826 					log_errx(1, "duplicated mountpoint "
827 					    "in %s, line %d", map, lineno);
828 				}
829 				if (options2 != NULL || location != NULL) {
830 					log_errx(1, "mountpoint out of order "
831 					    "in %s, line %d", map, lineno);
832 				}
833 				mountpoint = checked_strdup(yytext);
834 				goto again;
835 			}
836 
837 			if (yytext[0] == '-') {
838 				if (options2 != NULL) {
839 					log_errx(1, "duplicated options "
840 					    "in %s, line %d", map, lineno);
841 				}
842 				if (location != NULL) {
843 					log_errx(1, "options out of order "
844 					    "in %s, line %d", map, lineno);
845 				}
846 				options2 = checked_strdup(yytext + 1);
847 				goto again;
848 			}
849 
850 			if (location != NULL) {
851 				log_errx(1, "too many arguments "
852 				    "in %s, line %d", map, lineno);
853 			}
854 
855 			/*
856 			 * If location field starts with colon, e.g. ":/dev/cd0",
857 			 * then strip it.
858 			 */
859 			if (yytext[0] == ':') {
860 				location = checked_strdup(yytext + 1);
861 				if (location[0] == '\0') {
862 					log_errx(1, "empty location in %s, "
863 					    "line %d", map, lineno);
864 				}
865 			} else {
866 				location = checked_strdup(yytext);
867 			}
868 
869 			if (mountpoint == NULL)
870 				mountpoint = checked_strdup("/");
871 			if (options2 == NULL)
872 				options2 = checked_strdup("");
873 
874 #if 0
875 			log_debugx("adding map node, %s %s %s",
876 			    mountpoint, options2, location);
877 #endif
878 			node_new(node, mountpoint, options2, location,
879 			    map, lineno);
880 			mountpoint = options2 = location = NULL;
881 again:
882 			ret = yylex();
883 			if (ret == 0 || ret == NEWLINE) {
884 				if (mountpoint != NULL || options2 != NULL ||
885 				    location != NULL) {
886 					log_errx(1, "truncated entry "
887 					    "in %s, line %d", map, lineno);
888 				}
889 				break;
890 			}
891 		}
892 	}
893 }
894 
895 /*
896  * Parse output of a special map called without argument.  It is a list
897  * of keys, separated by newlines.  They can contain whitespace, so use
898  * getline(3) instead of lexer used for maps.
899  */
900 static void
901 parse_map_keys_yyin(struct node *parent, const char *map)
902 {
903 	char *line = NULL, *key;
904 	size_t linecap = 0;
905 	ssize_t linelen;
906 
907 	lineno = 1;
908 
909 	for (;;) {
910 		linelen = getline(&line, &linecap, yyin);
911 		if (linelen < 0) {
912 			/*
913 			 * End of file.
914 			 */
915 			break;
916 		}
917 		if (linelen <= 1) {
918 			/*
919 			 * Empty line, consisting of just the newline.
920 			 */
921 			continue;
922 		}
923 
924 		/*
925 		 * "-1" to strip the trailing newline.
926 		 */
927 		key = strndup(line, linelen - 1);
928 
929 		log_debugx("adding key \"%s\"", key);
930 		node_new(parent, key, NULL, NULL, map, lineno);
931 		lineno++;
932 	}
933 	free(line);
934 }
935 
936 static bool
937 file_is_executable(const char *path)
938 {
939 	struct stat sb;
940 	int error;
941 
942 	error = stat(path, &sb);
943 	if (error != 0)
944 		log_err(1, "cannot stat %s", path);
945 	if ((sb.st_mode & S_IXUSR) || (sb.st_mode & S_IXGRP) ||
946 	    (sb.st_mode & S_IXOTH))
947 		return (true);
948 	return (false);
949 }
950 
951 /*
952  * Parse a special map, e.g. "-hosts".
953  */
954 static void
955 parse_special_map(struct node *parent, const char *map, const char *key)
956 {
957 	char *path;
958 	int error, ret;
959 
960 	assert(map[0] == '-');
961 
962 	/*
963 	 * +1 to skip leading "-" in map name.
964 	 */
965 	ret = asprintf(&path, "%s/special_%s", AUTO_SPECIAL_PREFIX, map + 1);
966 	if (ret < 0)
967 		log_err(1, "asprintf");
968 
969 	yyin = auto_popen(path, key, NULL);
970 	assert(yyin != NULL);
971 
972 	if (key == NULL) {
973 		parse_map_keys_yyin(parent, map);
974 	} else {
975 		parse_map_yyin(parent, map, key);
976 	}
977 
978 	error = auto_pclose(yyin);
979 	yyin = NULL;
980 	if (error != 0)
981 		log_errx(1, "failed to handle special map \"%s\"", map);
982 
983 	node_expand_includes(parent, false);
984 	node_expand_direct_maps(parent);
985 
986 	free(path);
987 }
988 
989 /*
990  * Retrieve and parse map from directory services, e.g. LDAP.
991  * Note that it is different from executable maps, in that
992  * the include script outputs the whole map to standard output
993  * (as opposed to executable maps that only output a single
994  * entry, without the key), and it takes the map name as an
995  * argument, instead of key.
996  */
997 static void
998 parse_included_map(struct node *parent, const char *map)
999 {
1000 	int error;
1001 
1002 	assert(map[0] != '-');
1003 	assert(map[0] != '/');
1004 
1005 	error = access(AUTO_INCLUDE_PATH, F_OK);
1006 	if (error != 0) {
1007 		log_errx(1, "directory services not configured;"
1008 		    " %s does not exist", AUTO_INCLUDE_PATH);
1009 	}
1010 
1011 	yyin = auto_popen(AUTO_INCLUDE_PATH, map, NULL);
1012 	assert(yyin != NULL);
1013 
1014 	parse_map_yyin(parent, map, NULL);
1015 
1016 	error = auto_pclose(yyin);
1017 	yyin = NULL;
1018 	if (error != 0)
1019 		log_errx(1, "failed to handle remote map \"%s\"", map);
1020 
1021 	node_expand_includes(parent, false);
1022 	node_expand_direct_maps(parent);
1023 }
1024 
1025 void
1026 parse_map(struct node *parent, const char *map, const char *key,
1027     bool *wildcards)
1028 {
1029 	char *path = NULL;
1030 	int error, ret;
1031 	bool executable;
1032 
1033 	assert(map != NULL);
1034 	assert(map[0] != '\0');
1035 
1036 	log_debugx("parsing map \"%s\"", map);
1037 
1038 	if (wildcards != NULL)
1039 		*wildcards = false;
1040 
1041 	if (map[0] == '-') {
1042 		if (wildcards != NULL)
1043 			*wildcards = true;
1044 		return (parse_special_map(parent, map, key));
1045 	}
1046 
1047 	if (map[0] == '/') {
1048 		path = checked_strdup(map);
1049 	} else {
1050 		ret = asprintf(&path, "%s/%s", AUTO_MAP_PREFIX, map);
1051 		if (ret < 0)
1052 			log_err(1, "asprintf");
1053 		log_debugx("map \"%s\" maps to \"%s\"", map, path);
1054 
1055 		/*
1056 		 * See if the file exists.  If not, try to obtain the map
1057 		 * from directory services.
1058 		 */
1059 		error = access(path, F_OK);
1060 		if (error != 0) {
1061 			log_debugx("map file \"%s\" does not exist; falling "
1062 			    "back to directory services", path);
1063 			return (parse_included_map(parent, map));
1064 		}
1065 	}
1066 
1067 	executable = file_is_executable(path);
1068 
1069 	if (executable) {
1070 		log_debugx("map \"%s\" is executable", map);
1071 
1072 		if (wildcards != NULL)
1073 			*wildcards = true;
1074 
1075 		if (key != NULL) {
1076 			yyin = auto_popen(path, key, NULL);
1077 		} else {
1078 			yyin = auto_popen(path, NULL);
1079 		}
1080 		assert(yyin != NULL);
1081 	} else {
1082 		yyin = fopen(path, "r");
1083 		if (yyin == NULL)
1084 			log_err(1, "unable to open \"%s\"", path);
1085 	}
1086 
1087 	free(path);
1088 	path = NULL;
1089 
1090 	parse_map_yyin(parent, map, executable ? key : NULL);
1091 
1092 	if (executable) {
1093 		error = auto_pclose(yyin);
1094 		yyin = NULL;
1095 		if (error != 0) {
1096 			log_errx(1, "failed to handle executable map \"%s\"",
1097 			    map);
1098 		}
1099 	} else {
1100 		fclose(yyin);
1101 	}
1102 	yyin = NULL;
1103 
1104 	log_debugx("done parsing map \"%s\"", map);
1105 
1106 	node_expand_includes(parent, false);
1107 	node_expand_direct_maps(parent);
1108 }
1109 
1110 static void
1111 parse_master_yyin(struct node *root, const char *master)
1112 {
1113 	char *mountpoint = NULL, *map = NULL, *options = NULL;
1114 	int ret;
1115 
1116 	/*
1117 	 * XXX: 1 gives incorrect values; wtf?
1118 	 */
1119 	lineno = 0;
1120 
1121 	for (;;) {
1122 		ret = yylex();
1123 		if (ret == 0 || ret == NEWLINE) {
1124 			if (mountpoint != NULL) {
1125 				//log_debugx("adding map for %s", mountpoint);
1126 				node_new_map(root, mountpoint, options, map,
1127 				    master, lineno);
1128 			}
1129 			if (ret == 0) {
1130 				break;
1131 			} else {
1132 				mountpoint = map = options = NULL;
1133 				continue;
1134 			}
1135 		}
1136 		if (mountpoint == NULL) {
1137 			mountpoint = checked_strdup(yytext);
1138 		} else if (map == NULL) {
1139 			map = checked_strdup(yytext);
1140 		} else if (options == NULL) {
1141 			/*
1142 			 * +1 to skip leading "-".
1143 			 */
1144 			options = checked_strdup(yytext + 1);
1145 		} else {
1146 			log_errx(1, "too many arguments at %s, line %d",
1147 			    master, lineno);
1148 		}
1149 	}
1150 }
1151 
1152 void
1153 parse_master(struct node *root, const char *master)
1154 {
1155 
1156 	log_debugx("parsing auto_master file at \"%s\"", master);
1157 
1158 	yyin = fopen(master, "r");
1159 	if (yyin == NULL)
1160 		err(1, "unable to open %s", master);
1161 
1162 	parse_master_yyin(root, master);
1163 
1164 	fclose(yyin);
1165 	yyin = NULL;
1166 
1167 	log_debugx("done parsing \"%s\"", master);
1168 
1169 	node_expand_includes(root, true);
1170 	node_expand_direct_maps(root);
1171 }
1172 
1173 /*
1174  * Two things daemon(3) does, that we actually also want to do
1175  * when running in foreground, is closing the stdin and chdiring
1176  * to "/".  This is what we do here.
1177  */
1178 void
1179 lesser_daemon(void)
1180 {
1181 	int error, fd;
1182 
1183 	error = chdir("/");
1184 	if (error != 0)
1185 		log_warn("chdir");
1186 
1187 	fd = open(_PATH_DEVNULL, O_RDWR, 0);
1188 	if (fd < 0) {
1189 		log_warn("cannot open %s", _PATH_DEVNULL);
1190 		return;
1191 	}
1192 
1193 	error = dup2(fd, STDIN_FILENO);
1194 	if (error != 0)
1195 		log_warn("dup2");
1196 
1197 	error = close(fd);
1198 	if (error != 0) {
1199 		/* Bloody hell. */
1200 		log_warn("close");
1201 	}
1202 }
1203 
1204 int
1205 main(int argc, char **argv)
1206 {
1207 	char *cmdname;
1208 
1209 	if (argv[0] == NULL)
1210 		log_errx(1, "NULL command name");
1211 
1212 	cmdname = basename(argv[0]);
1213 
1214 	if (strcmp(cmdname, "automount") == 0)
1215 		return (main_automount(argc, argv));
1216 	else if (strcmp(cmdname, "automountd") == 0)
1217 		return (main_automountd(argc, argv));
1218 	else if (strcmp(cmdname, "autounmountd") == 0)
1219 		return (main_autounmountd(argc, argv));
1220 	else
1221 		log_errx(1, "binary name should be either \"automount\", "
1222 		    "\"automountd\", or \"autounmountd\"");
1223 }
1224