xref: /netbsd-src/usr.sbin/autofs/common.c (revision 5628820aad1597d6c95795148f19b1e219c2967f)
1 /*	$NetBSD: common.c,v 1.5 2022/05/04 11:27:54 tkusumi Exp $	*/
2 
3 /*-
4  * Copyright (c) 2017 The NetBSD Foundation, Inc.
5  * Copyright (c) 2016 The DragonFly Project
6  * Copyright (c) 2014 The FreeBSD Foundation
7  * All rights reserved.
8  *
9  * This code is derived from software contributed to The NetBSD Foundation
10  * by Tomohiro Kusumi <kusumi.tomohiro@gmail.com>.
11  *
12  * This software was developed by Edward Tomasz Napierala under sponsorship
13  * from the FreeBSD Foundation.
14  *
15  * Redistribution and use in source and binary forms, with or without
16  * modification, are permitted provided that the following conditions
17  * are met:
18  * 1. Redistributions of source code must retain the above copyright
19  *    notice, this list of conditions and the following disclaimer.
20  * 2. Redistributions in binary form must reproduce the above copyright
21  *    notice, this list of conditions and the following disclaimer in the
22  *    documentation and/or other materials provided with the distribution.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  *
36  * $FreeBSD: head/usr.sbin/autofs/common.c 303527 2016-07-30 01:10:05Z bapt $
37  */
38 #include <sys/cdefs.h>
39 __RCSID("$NetBSD: common.c,v 1.5 2022/05/04 11:27:54 tkusumi Exp $");
40 
41 #include <sys/types.h>
42 #include <sys/stat.h>
43 #include <assert.h>
44 #include <err.h>
45 #include <errno.h>
46 #include <fcntl.h>
47 #include <libgen.h>
48 #include <paths.h>
49 #include <stdio.h>
50 #include <stdlib.h>
51 #include <string.h>
52 #include <unistd.h>
53 
54 #include "common.h"
55 
56 extern FILE *yyin;
57 extern char *yytext;
58 extern int yylex(void);
59 
60 static void	parse_master_yyin(struct node *root, const char *master);
61 static void	parse_map_yyin(struct node *parent, const char *map,
62 		    const char *executable_key);
63 
64 char *
checked_strdup(const char * s)65 checked_strdup(const char *s)
66 {
67 	char *c;
68 
69 	assert(s != NULL);
70 
71 	c = strdup(s);
72 	if (c == NULL)
73 		log_err(1, "strdup");
74 	return c;
75 }
76 
77 /*
78  * Concatenate two strings, inserting separator between them, unless not needed.
79  */
80 char *
concat(const char * s1,char separator,const char * s2)81 concat(const char *s1, char separator, const char *s2)
82 {
83 	char *result;
84 	char s1last, s2first;
85 	int ret;
86 
87 	if (s1 == NULL)
88 		s1 = "";
89 	if (s2 == NULL)
90 		s2 = "";
91 
92 	if (s1[0] == '\0')
93 		s1last = '\0';
94 	else
95 		s1last = s1[strlen(s1) - 1];
96 
97 	s2first = s2[0];
98 
99 	if (s1last == separator && s2first == separator) {
100 		/*
101 		 * If s1 ends with the separator and s2 begins with
102 		 * it - skip the latter; otherwise concatenating "/"
103 		 * and "/foo" would end up returning "//foo".
104 		 */
105 		ret = asprintf(&result, "%s%s", s1, s2 + 1);
106 	} else if (s1last == separator || s2first == separator ||
107 	    s1[0] == '\0' || s2[0] == '\0') {
108 		ret = asprintf(&result, "%s%s", s1, s2);
109 	} else {
110 		ret = asprintf(&result, "%s%c%s", s1, separator, s2);
111 	}
112 	if (ret < 0)
113 		log_err(1, "asprintf");
114 
115 #if 0
116 	log_debugx("%s: got %s and %s, returning %s", __func__, s1, s2, result);
117 #endif
118 
119 	return result;
120 }
121 
122 void
create_directory(const char * path)123 create_directory(const char *path)
124 {
125 	char *component, *copy, *tofree, *partial, *tmp;
126 	int error;
127 
128 	assert(path[0] == '/');
129 
130 	/*
131 	 * +1 to skip the leading slash.
132 	 */
133 	copy = tofree = checked_strdup(path + 1);
134 
135 	partial = checked_strdup("/");
136 	for (;;) {
137 		component = strsep(&copy, "/");
138 		if (component == NULL)
139 			break;
140 		tmp = concat(partial, '/', component);
141 		free(partial);
142 		partial = tmp;
143 		//log_debugx("creating \"%s\"", partial);
144 		error = mkdir(partial, 0755);
145 		if (error != 0 && errno != EEXIST) {
146 			log_warn("cannot create %s", partial);
147 			return;
148 		}
149 	}
150 
151 	free(tofree);
152 }
153 
154 struct node *
node_new_root(void)155 node_new_root(void)
156 {
157 	struct node *n;
158 
159 	n = calloc(1, sizeof(*n));
160 	if (n == NULL)
161 		log_err(1, "calloc");
162 	// XXX
163 	n->n_key = checked_strdup("/");
164 	n->n_options = checked_strdup("");
165 
166 	TAILQ_INIT(&n->n_children);
167 
168 	return n;
169 }
170 
171 struct node *
node_new(struct node * parent,char * key,char * options,char * location,const char * config_file,int config_line)172 node_new(struct node *parent, char *key, char *options, char *location,
173     const char *config_file, int config_line)
174 {
175 	struct node *n;
176 
177 	n = calloc(1, sizeof(*n));
178 	if (n == NULL)
179 		log_err(1, "calloc");
180 
181 	TAILQ_INIT(&n->n_children);
182 	assert(key != NULL);
183 	assert(key[0] != '\0');
184 	n->n_key = key;
185 	if (options != NULL)
186 		n->n_options = options;
187 	else
188 		n->n_options = strdup("");
189 	n->n_location = location;
190 	assert(config_file != NULL);
191 	n->n_config_file = config_file;
192 	assert(config_line >= 0);
193 	n->n_config_line = config_line;
194 
195 	assert(parent != NULL);
196 	n->n_parent = parent;
197 	TAILQ_INSERT_TAIL(&parent->n_children, n, n_next);
198 
199 	return n;
200 }
201 
202 struct node *
node_new_map(struct node * parent,char * key,char * options,char * map,const char * config_file,int config_line)203 node_new_map(struct node *parent, char *key, char *options, char *map,
204     const char *config_file, int config_line)
205 {
206 	struct node *n;
207 
208 	n = calloc(1, sizeof(*n));
209 	if (n == NULL)
210 		log_err(1, "calloc");
211 
212 	TAILQ_INIT(&n->n_children);
213 	assert(key != NULL);
214 	assert(key[0] != '\0');
215 	n->n_key = key;
216 	if (options != NULL)
217 		n->n_options = options;
218 	else
219 		n->n_options = strdup("");
220 	n->n_map = map;
221 	assert(config_file != NULL);
222 	n->n_config_file = config_file;
223 	assert(config_line >= 0);
224 	n->n_config_line = config_line;
225 
226 	assert(parent != NULL);
227 	n->n_parent = parent;
228 	TAILQ_INSERT_TAIL(&parent->n_children, n, n_next);
229 
230 	return n;
231 }
232 
233 static struct node *
node_duplicate(const struct node * o,struct node * parent)234 node_duplicate(const struct node *o, struct node *parent)
235 {
236 	const struct node *child;
237 	struct node *n;
238 
239 	if (parent == NULL)
240 		parent = o->n_parent;
241 
242 	n = node_new(parent, o->n_key, o->n_options, o->n_location,
243 	    o->n_config_file, o->n_config_line);
244 
245 	TAILQ_FOREACH(child, &o->n_children, n_next)
246 		node_duplicate(child, n);
247 
248 	return n;
249 }
250 
251 static void
node_delete(struct node * n)252 node_delete(struct node *n)
253 {
254 	struct node *child, *tmp;
255 
256 	assert (n != NULL);
257 
258 	TAILQ_FOREACH_SAFE(child, &n->n_children, n_next, tmp)
259 		node_delete(child);
260 
261 	if (n->n_parent != NULL)
262 		TAILQ_REMOVE(&n->n_parent->n_children, n, n_next);
263 
264 	free(n);
265 }
266 
267 /*
268  * Move (reparent) node 'n' to make it sibling of 'previous', placed
269  * just after it.
270  */
271 static void
node_move_after(struct node * n,struct node * previous)272 node_move_after(struct node *n, struct node *previous)
273 {
274 
275 	TAILQ_REMOVE(&n->n_parent->n_children, n, n_next);
276 	n->n_parent = previous->n_parent;
277 	TAILQ_INSERT_AFTER(&previous->n_parent->n_children, previous, n, n_next);
278 }
279 
280 static void
node_expand_includes(struct node * root,bool is_master)281 node_expand_includes(struct node *root, bool is_master)
282 {
283 	struct node *n, *n2, *tmp, *tmp2, *tmproot;
284 	int error;
285 
286 	TAILQ_FOREACH_SAFE(n, &root->n_children, n_next, tmp) {
287 		if (n->n_key[0] != '+')
288 			continue;
289 
290 		error = access(AUTO_INCLUDE_PATH, F_OK);
291 		if (error != 0) {
292 			log_errx(1, "directory services not configured; "
293 			    "%s does not exist", AUTO_INCLUDE_PATH);
294 		}
295 
296 		/*
297 		 * "+1" to skip leading "+".
298 		 */
299 		yyin = auto_popen(AUTO_INCLUDE_PATH, n->n_key + 1, NULL);
300 		assert(yyin != NULL);
301 
302 		tmproot = node_new_root();
303 		if (is_master)
304 			parse_master_yyin(tmproot, n->n_key);
305 		else
306 			parse_map_yyin(tmproot, n->n_key, NULL);
307 
308 		error = auto_pclose(yyin);
309 		yyin = NULL;
310 		if (error != 0) {
311 			log_errx(1, "failed to handle include \"%s\"",
312 			    n->n_key);
313 		}
314 
315 		/*
316 		 * Entries to be included are now in tmproot.  We need to merge
317 		 * them with the rest, preserving their place and ordering.
318 		 */
319 		TAILQ_FOREACH_REVERSE_SAFE(n2,
320 		    &tmproot->n_children, nodehead, n_next, tmp2) {
321 			node_move_after(n2, n);
322 		}
323 
324 		node_delete(n);
325 		node_delete(tmproot);
326 	}
327 }
328 
329 static char *
expand_ampersand(char * string,const char * key)330 expand_ampersand(char *string, const char *key)
331 {
332 	char c, *expanded;
333 	int ret;
334 	size_t i, before_len = 0;
335 	bool backslashed = false;
336 
337 	assert(key[0] != '\0');
338 
339 	expanded = checked_strdup(string);
340 
341 	for (i = 0; string[i] != '\0'; i++) {
342 		c = string[i];
343 		if (c == '\\' && backslashed == false) {
344 			backslashed = true;
345 			continue;
346 		}
347 		if (backslashed) {
348 			backslashed = false;
349 			continue;
350 		}
351 		backslashed = false;
352 		if (c != '&')
353 			continue;
354 
355 		/*
356 		 * The 'before_len' variable contains the number
357 		 * of characters before the '&'.
358 		 */
359 		before_len = i;
360 		//assert(i < strlen(string));
361 
362 		ret = asprintf(&expanded, "%.*s%s%s",
363 		    (int)before_len, string, key, string + before_len + 1);
364 		if (ret < 0)
365 			log_err(1, "asprintf");
366 
367 		//log_debugx("\"%s\" expanded with key \"%s\" to \"%s\"",
368 		//    string, key, expanded);
369 
370 		/*
371 		 * Figure out where to start searching for next variable.
372 		 */
373 		string = expanded;
374 		i = before_len + strlen(key);
375 		if (i == strlen(string))
376 			break;
377 		backslashed = false;
378 		//assert(i < strlen(string));
379 	}
380 
381 	return expanded;
382 }
383 
384 /*
385  * Expand "&" in n_location.  If the key is NULL, try to use
386  * key from map entries themselves.  Keep in mind that maps
387  * consist of tho levels of node structures, the key is one
388  * level up.
389  *
390  * Variant with NULL key is for "automount -LL".
391  */
392 void
node_expand_ampersand(struct node * n,const char * key)393 node_expand_ampersand(struct node *n, const char *key)
394 {
395 	struct node *child;
396 
397 	if (n->n_location != NULL) {
398 		if (key == NULL) {
399 			if (n->n_parent != NULL &&
400 			    strcmp(n->n_parent->n_key, "*") != 0) {
401 				n->n_location = expand_ampersand(n->n_location,
402 				    n->n_parent->n_key);
403 			}
404 		} else {
405 			n->n_location = expand_ampersand(n->n_location, key);
406 		}
407 	}
408 
409 	TAILQ_FOREACH(child, &n->n_children, n_next)
410 		node_expand_ampersand(child, key);
411 }
412 
413 /*
414  * Expand "*" in n_key.
415  */
416 void
node_expand_wildcard(struct node * n,const char * key)417 node_expand_wildcard(struct node *n, const char *key)
418 {
419 	struct node *child, *expanded;
420 
421 	assert(key != NULL);
422 
423 	if (strcmp(n->n_key, "*") == 0) {
424 		expanded = node_duplicate(n, NULL);
425 		expanded->n_key = checked_strdup(key);
426 		node_move_after(expanded, n);
427 	}
428 
429 	TAILQ_FOREACH(child, &n->n_children, n_next)
430 		node_expand_wildcard(child, key);
431 }
432 
433 int
node_expand_defined(struct node * n)434 node_expand_defined(struct node *n)
435 {
436 	struct node *child;
437 	int error, cummulative_error = 0;
438 
439 	if (n->n_location != NULL) {
440 		n->n_location = defined_expand(n->n_location);
441 		if (n->n_location == NULL) {
442 			log_warnx("failed to expand location for %s",
443 			    node_path(n));
444 			return EINVAL;
445 		}
446 	}
447 
448 	TAILQ_FOREACH(child, &n->n_children, n_next) {
449 		error = node_expand_defined(child);
450 		if (error != 0 && cummulative_error == 0)
451 			cummulative_error = error;
452 	}
453 
454 	return cummulative_error;
455 }
456 
457 static bool
node_is_direct_key(const struct node * n)458 node_is_direct_key(const struct node *n)
459 {
460 
461 	return n->n_parent != NULL && n->n_parent->n_parent == NULL &&
462 	    strcmp(n->n_key, "/-") == 0;
463 }
464 
465 bool
node_is_direct_map(const struct node * n)466 node_is_direct_map(const struct node *n)
467 {
468 
469 	for (;;) {
470 		assert(n->n_parent != NULL);
471 		if (n->n_parent->n_parent == NULL)
472 			break;
473 		n = n->n_parent;
474 	}
475 
476 	return node_is_direct_key(n);
477 }
478 
479 bool
node_has_wildcards(const struct node * n)480 node_has_wildcards(const struct node *n)
481 {
482 	const struct node *child;
483 
484 	TAILQ_FOREACH(child, &n->n_children, n_next) {
485 		if (strcmp(child->n_key, "*") == 0)
486 			return true;
487 	}
488 
489 	return false;
490 }
491 
492 static void
node_expand_maps(struct node * n,bool indirect)493 node_expand_maps(struct node *n, bool indirect)
494 {
495 	struct node *child, *tmp;
496 
497 	TAILQ_FOREACH_SAFE(child, &n->n_children, n_next, tmp) {
498 		if (node_is_direct_map(child)) {
499 			if (indirect)
500 				continue;
501 		} else {
502 			if (indirect == false)
503 				continue;
504 		}
505 
506 		/*
507 		 * This is the first-level map node; the one that contains
508 		 * the key and subnodes with mountpoints and actual map names.
509 		 */
510 		if (child->n_map == NULL)
511 			continue;
512 
513 		if (indirect) {
514 			log_debugx("map \"%s\" is an indirect map, parsing",
515 			    child->n_map);
516 		} else {
517 			log_debugx("map \"%s\" is a direct map, parsing",
518 			    child->n_map);
519 		}
520 		parse_map(child, child->n_map, NULL, NULL);
521 	}
522 }
523 
524 static void
node_expand_direct_maps(struct node * n)525 node_expand_direct_maps(struct node *n)
526 {
527 
528 	node_expand_maps(n, false);
529 }
530 
531 void
node_expand_indirect_maps(struct node * n)532 node_expand_indirect_maps(struct node *n)
533 {
534 
535 	node_expand_maps(n, true);
536 }
537 
538 static char *
node_path_x(const struct node * n,char * x)539 node_path_x(const struct node *n, char *x)
540 {
541 	char *path;
542 
543 	if (n->n_parent == NULL)
544 		return x;
545 
546 	/*
547 	 * Return "/-" for direct maps only if we were asked for path
548 	 * to the "/-" node itself, not to any of its subnodes.
549 	 */
550 	if (node_is_direct_key(n) && x[0] != '\0')
551 		return x;
552 
553 	assert(n->n_key[0] != '\0');
554 	path = concat(n->n_key, '/', x);
555 	free(x);
556 
557 	return node_path_x(n->n_parent, path);
558 }
559 
560 /*
561  * Return full path for node, consisting of concatenated
562  * paths of node itself and all its parents, up to the root.
563  */
564 char *
node_path(const struct node * n)565 node_path(const struct node *n)
566 {
567 	char *path;
568 	size_t len;
569 
570 	path = node_path_x(n, checked_strdup(""));
571 
572 	/*
573 	 * Strip trailing slash, unless the whole path is "/".
574 	 */
575 	len = strlen(path);
576 	if (len > 1 && path[len - 1] == '/')
577 		path[len - 1] = '\0';
578 
579 	return path;
580 }
581 
582 static char *
node_options_x(const struct node * n,char * x)583 node_options_x(const struct node *n, char *x)
584 {
585 	char *options;
586 
587 	if (n == NULL)
588 		return x;
589 
590 	options = concat(x, ',', n->n_options);
591 	free(x);
592 
593 	return node_options_x(n->n_parent, options);
594 }
595 
596 /*
597  * Return options for node, consisting of concatenated
598  * options from the node itself and all its parents,
599  * up to the root.
600  */
601 char *
node_options(const struct node * n)602 node_options(const struct node *n)
603 {
604 
605 	return node_options_x(n, checked_strdup(""));
606 }
607 
608 static void
node_print_indent(const struct node * n,const char * cmdline_options,int indent)609 node_print_indent(const struct node *n, const char *cmdline_options,
610     int indent)
611 {
612 	const struct node *child, *first_child;
613 	char *path, *options, *tmp;
614 
615 	path = node_path(n);
616 	tmp = node_options(n);
617 	options = concat(cmdline_options, ',', tmp);
618 	free(tmp);
619 
620 	/*
621 	 * Do not show both parent and child node if they have the same
622 	 * mountpoint; only show the child node.  This means the typical,
623 	 * "key location", map entries are shown in a single line;
624 	 * the "key mountpoint1 location2 mountpoint2 location2" entries
625 	 * take multiple lines.
626 	 */
627 	first_child = TAILQ_FIRST(&n->n_children);
628 	if (first_child == NULL || TAILQ_NEXT(first_child, n_next) != NULL ||
629 	    strcmp(path, node_path(first_child)) != 0) {
630 		assert(n->n_location == NULL || n->n_map == NULL);
631 		printf("%*.s%-*s %s%-*s %-*s # %s map %s at %s:%d\n",
632 		    indent, "",
633 		    25 - indent,
634 		    path,
635 		    options[0] != '\0' ? "-" : " ",
636 		    20,
637 		    options[0] != '\0' ? options : "",
638 		    20,
639 		    n->n_location != NULL ? n->n_location : n->n_map != NULL ? n->n_map : "",
640 		    node_is_direct_map(n) ? "direct" : "indirect",
641 		    indent == 0 ? "referenced" : "defined",
642 		    n->n_config_file, n->n_config_line);
643 	}
644 
645 	free(path);
646 	free(options);
647 
648 	TAILQ_FOREACH(child, &n->n_children, n_next)
649 		node_print_indent(child, cmdline_options, indent + 2);
650 }
651 
652 /*
653  * Recursively print node with all its children.  The cmdline_options
654  * argument is used for additional options to be prepended to all the
655  * others - usually those are the options passed by command line.
656  */
657 void
node_print(const struct node * n,const char * cmdline_options)658 node_print(const struct node *n, const char *cmdline_options)
659 {
660 	const struct node *child;
661 
662 	TAILQ_FOREACH(child, &n->n_children, n_next)
663 		node_print_indent(child, cmdline_options, 0);
664 }
665 
666 static struct node *
node_find_x(struct node * node,const char * path)667 node_find_x(struct node *node, const char *path)
668 {
669 	struct node *child, *found;
670 	char *tmp;
671 	size_t tmplen;
672 
673 	//log_debugx("looking up %s in %s", path, node_path(node));
674 
675 	if (!node_is_direct_key(node)) {
676 		tmp = node_path(node);
677 		tmplen = strlen(tmp);
678 		if (strncmp(tmp, path, tmplen) != 0) {
679 			free(tmp);
680 			return NULL;
681 		}
682 		if (path[tmplen] != '/' && path[tmplen] != '\0') {
683 			/*
684 			 * If we have two map entries like 'foo' and 'foobar', make
685 			 * sure the search for 'foobar' won't match 'foo' instead.
686 			 */
687 			free(tmp);
688 			return NULL;
689 		}
690 		free(tmp);
691 	}
692 
693 	TAILQ_FOREACH(child, &node->n_children, n_next) {
694 		found = node_find_x(child, path);
695 		if (found != NULL)
696 			return found;
697 	}
698 
699 	if (node->n_parent == NULL || node_is_direct_key(node))
700 		return NULL;
701 
702 	return node;
703 }
704 
705 struct node *
node_find(struct node * root,const char * path)706 node_find(struct node *root, const char *path)
707 {
708 	struct node *node;
709 
710 	assert(root->n_parent == NULL);
711 
712 	node = node_find_x(root, path);
713 	if (node != NULL)
714 		assert(node != root);
715 
716 	return node;
717 }
718 
719 /*
720  * Canonical form of a map entry looks like this:
721  *
722  * key [-options] [ [/mountpoint] [-options2] location ... ]
723  *
724  * Entries for executable maps are slightly different, as they
725  * lack the 'key' field and are always single-line; the key field
726  * for those maps is taken from 'executable_key' argument.
727  *
728  * We parse it in such a way that a map always has two levels - first
729  * for key, and the second, for the mountpoint.
730  */
731 static void
parse_map_yyin(struct node * parent,const char * map,const char * executable_key)732 parse_map_yyin(struct node *parent, const char *map, const char *executable_key)
733 {
734 	char *key = NULL, *options = NULL, *mountpoint = NULL,
735 	    *options2 = NULL, *location = NULL;
736 	int ret;
737 	struct node *node;
738 
739 	lineno = 1;
740 
741 	if (executable_key != NULL)
742 		key = checked_strdup(executable_key);
743 
744 	for (;;) {
745 		ret = yylex();
746 		if (ret == 0 || ret == NEWLINE) {
747 			/*
748 			 * In case of executable map, the key is always
749 			 * non-NULL, even if the map is empty.  So, make sure
750 			 * we don't fail empty maps here.
751 			 */
752 			if ((key != NULL && executable_key == NULL) ||
753 			    options != NULL) {
754 				log_errx(1, "truncated entry at %s, line %d",
755 				    map, lineno);
756 			}
757 			if (ret == 0 || executable_key != NULL) {
758 				/*
759 				 * End of file.
760 				 */
761 				break;
762 			} else {
763 				key = options = NULL;
764 				continue;
765 			}
766 		}
767 		if (key == NULL) {
768 			key = checked_strdup(yytext);
769 			if (key[0] == '+') {
770 				node_new(parent, key, NULL, NULL, map, lineno);
771 				key = options = NULL;
772 				continue;
773 			}
774 			continue;
775 		} else if (yytext[0] == '-') {
776 			if (options != NULL) {
777 				log_errx(1, "duplicated options at %s, line %d",
778 				    map, lineno);
779 			}
780 			/*
781 			 * +1 to skip leading "-".
782 			 */
783 			options = checked_strdup(yytext + 1);
784 			continue;
785 		}
786 
787 		/*
788 		 * We cannot properly handle a situation where the map key
789 		 * is "/".  Ignore such entries.
790 		 *
791 		 * XXX: According to Piete Brooks, Linux automounter uses
792 		 *	"/" as a wildcard character in LDAP maps.  Perhaps
793 		 *	we should work around this braindamage by substituting
794 		 *	"*" for "/"?
795 		 */
796 		if (strcmp(key, "/") == 0) {
797 			log_warnx("nonsensical map key \"/\" at %s, line %d; "
798 			    "ignoring map entry ", map, lineno);
799 
800 			/*
801 			 * Skip the rest of the entry.
802 			 */
803 			do {
804 				ret = yylex();
805 			} while (ret != 0 && ret != NEWLINE);
806 
807 			key = options = NULL;
808 			continue;
809 		}
810 
811 		//log_debugx("adding map node, %s", key);
812 		node = node_new(parent, key, options, NULL, map, lineno);
813 		key = options = NULL;
814 
815 		for (;;) {
816 			if (yytext[0] == '/') {
817 				if (mountpoint != NULL) {
818 					log_errx(1, "duplicated mountpoint "
819 					    "in %s, line %d", map, lineno);
820 				}
821 				if (options2 != NULL || location != NULL) {
822 					log_errx(1, "mountpoint out of order "
823 					    "in %s, line %d", map, lineno);
824 				}
825 				mountpoint = checked_strdup(yytext);
826 				goto again;
827 			}
828 
829 			if (yytext[0] == '-') {
830 				if (options2 != NULL) {
831 					log_errx(1, "duplicated options "
832 					    "in %s, line %d", map, lineno);
833 				}
834 				if (location != NULL) {
835 					log_errx(1, "options out of order "
836 					    "in %s, line %d", map, lineno);
837 				}
838 				options2 = checked_strdup(yytext + 1);
839 				goto again;
840 			}
841 
842 			if (location != NULL) {
843 				log_errx(1, "too many arguments "
844 				    "in %s, line %d", map, lineno);
845 			}
846 
847 			/*
848 			 * If location field starts with colon, e.g. ":/dev/cd0",
849 			 * then strip it.
850 			 */
851 			if (yytext[0] == ':') {
852 				location = checked_strdup(yytext + 1);
853 				if (location[0] == '\0') {
854 					log_errx(1, "empty location in %s, "
855 					    "line %d", map, lineno);
856 				}
857 			} else {
858 				location = checked_strdup(yytext);
859 			}
860 
861 			if (mountpoint == NULL)
862 				mountpoint = checked_strdup("/");
863 			if (options2 == NULL)
864 				options2 = checked_strdup("");
865 
866 #if 0
867 			log_debugx("adding map node, %s %s %s",
868 			    mountpoint, options2, location);
869 #endif
870 			node_new(node, mountpoint, options2, location,
871 			    map, lineno);
872 			mountpoint = options2 = location = NULL;
873 again:
874 			ret = yylex();
875 			if (ret == 0 || ret == NEWLINE) {
876 				if (mountpoint != NULL || options2 != NULL ||
877 				    location != NULL) {
878 					log_errx(1, "truncated entry "
879 					    "in %s, line %d", map, lineno);
880 				}
881 				break;
882 			}
883 		}
884 	}
885 }
886 
887 /*
888  * Parse output of a special map called without argument.  It is a list
889  * of keys, separated by newlines.  They can contain whitespace, so use
890  * getline(3) instead of lexer used for maps.
891  */
892 static void
parse_map_keys_yyin(struct node * parent,const char * map)893 parse_map_keys_yyin(struct node *parent, const char *map)
894 {
895 	char *line = NULL, *key;
896 	size_t linecap = 0;
897 	ssize_t linelen;
898 
899 	lineno = 1;
900 
901 	for (;;) {
902 		linelen = getline(&line, &linecap, yyin);
903 		if (linelen < 0) {
904 			/*
905 			 * End of file.
906 			 */
907 			break;
908 		}
909 		if (linelen <= 1) {
910 			/*
911 			 * Empty line, consisting of just the newline.
912 			 */
913 			continue;
914 		}
915 
916 		/*
917 		 * "-1" to strip the trailing newline.
918 		 */
919 		key = strndup(line, (size_t)linelen - 1);
920 
921 		log_debugx("adding key \"%s\"", key);
922 		node_new(parent, key, NULL, NULL, map, lineno);
923 		lineno++;
924 	}
925 	free(line);
926 }
927 
928 static bool
file_is_executable(const char * path)929 file_is_executable(const char *path)
930 {
931 	struct stat sb;
932 	int error;
933 
934 	error = stat(path, &sb);
935 	if (error != 0)
936 		log_err(1, "cannot stat %s", path);
937 	return (sb.st_mode & S_IXUSR) || (sb.st_mode & S_IXGRP) ||
938 	    (sb.st_mode & S_IXOTH);
939 }
940 
941 /*
942  * Parse a special map, e.g. "-hosts".
943  */
944 static void
parse_special_map(struct node * parent,const char * map,const char * key)945 parse_special_map(struct node *parent, const char *map, const char *key)
946 {
947 	char *path;
948 	int error, ret;
949 
950 	assert(map[0] == '-');
951 
952 	/*
953 	 * +1 to skip leading "-" in map name.
954 	 */
955 	ret = asprintf(&path, "%s/special_%s", AUTO_SPECIAL_PREFIX, map + 1);
956 	if (ret < 0)
957 		log_err(1, "asprintf");
958 
959 	yyin = auto_popen(path, key, NULL);
960 	assert(yyin != NULL);
961 
962 	if (key == NULL) {
963 		parse_map_keys_yyin(parent, map);
964 	} else {
965 		parse_map_yyin(parent, map, key);
966 	}
967 
968 	error = auto_pclose(yyin);
969 	yyin = NULL;
970 	if (error != 0)
971 		log_errx(1, "failed to handle special map \"%s\"", map);
972 
973 	node_expand_includes(parent, false);
974 	node_expand_direct_maps(parent);
975 
976 	free(path);
977 }
978 
979 /*
980  * Retrieve and parse map from directory services, e.g. LDAP.
981  * Note that it is different from executable maps, in that
982  * the include script outputs the whole map to standard output
983  * (as opposed to executable maps that only output a single
984  * entry, without the key), and it takes the map name as an
985  * argument, instead of key.
986  */
987 static void
parse_included_map(struct node * parent,const char * map)988 parse_included_map(struct node *parent, const char *map)
989 {
990 	int error;
991 
992 	assert(map[0] != '-');
993 	assert(map[0] != '/');
994 
995 	error = access(AUTO_INCLUDE_PATH, F_OK);
996 	if (error != 0) {
997 		log_errx(1, "directory services not configured;"
998 		    " %s does not exist", AUTO_INCLUDE_PATH);
999 	}
1000 
1001 	yyin = auto_popen(AUTO_INCLUDE_PATH, map, NULL);
1002 	assert(yyin != NULL);
1003 
1004 	parse_map_yyin(parent, map, NULL);
1005 
1006 	error = auto_pclose(yyin);
1007 	yyin = NULL;
1008 	if (error != 0)
1009 		log_errx(1, "failed to handle remote map \"%s\"", map);
1010 
1011 	node_expand_includes(parent, false);
1012 	node_expand_direct_maps(parent);
1013 }
1014 
1015 void
parse_map(struct node * parent,const char * map,const char * key,bool * wildcards)1016 parse_map(struct node *parent, const char *map, const char *key,
1017     bool *wildcards)
1018 {
1019 	char *path = NULL;
1020 	int error, ret;
1021 	bool executable;
1022 
1023 	assert(map != NULL);
1024 	assert(map[0] != '\0');
1025 
1026 	log_debugx("parsing map \"%s\"", map);
1027 
1028 	if (wildcards != NULL)
1029 		*wildcards = false;
1030 
1031 	if (map[0] == '-') {
1032 		if (wildcards != NULL)
1033 			*wildcards = true;
1034 		parse_special_map(parent, map, key);
1035 		return;
1036 	}
1037 
1038 	if (map[0] == '/') {
1039 		path = checked_strdup(map);
1040 	} else {
1041 		ret = asprintf(&path, "%s/%s", AUTO_MAP_PREFIX, map);
1042 		if (ret < 0)
1043 			log_err(1, "asprintf");
1044 		log_debugx("map \"%s\" maps to \"%s\"", map, path);
1045 
1046 		/*
1047 		 * See if the file exists.  If not, try to obtain the map
1048 		 * from directory services.
1049 		 */
1050 		error = access(path, F_OK);
1051 		if (error != 0) {
1052 			log_debugx("map file \"%s\" does not exist; falling "
1053 			    "back to directory services", path);
1054 			parse_included_map(parent, map);
1055 			return;
1056 		}
1057 	}
1058 
1059 	executable = file_is_executable(path);
1060 
1061 	if (executable) {
1062 		log_debugx("map \"%s\" is executable", map);
1063 
1064 		if (wildcards != NULL)
1065 			*wildcards = true;
1066 
1067 		if (key != NULL) {
1068 			yyin = auto_popen(path, key, NULL);
1069 		} else {
1070 			yyin = auto_popen(path, NULL);
1071 		}
1072 		assert(yyin != NULL);
1073 	} else {
1074 		yyin = fopen(path, "r");
1075 		if (yyin == NULL)
1076 			log_err(1, "unable to open \"%s\"", path);
1077 	}
1078 
1079 	free(path);
1080 	path = NULL;
1081 
1082 	parse_map_yyin(parent, map, executable ? key : NULL);
1083 
1084 	if (executable) {
1085 		error = auto_pclose(yyin);
1086 		yyin = NULL;
1087 		if (error != 0) {
1088 			log_errx(1, "failed to handle executable map \"%s\"",
1089 			    map);
1090 		}
1091 	} else {
1092 		fclose(yyin);
1093 	}
1094 	yyin = NULL;
1095 
1096 	log_debugx("done parsing map \"%s\"", map);
1097 
1098 	node_expand_includes(parent, false);
1099 	node_expand_direct_maps(parent);
1100 }
1101 
1102 static void
parse_master_yyin(struct node * root,const char * master)1103 parse_master_yyin(struct node *root, const char *master)
1104 {
1105 	char *mountpoint = NULL, *map = NULL, *options = NULL;
1106 	int ret;
1107 
1108 	/*
1109 	 * XXX: 1 gives incorrect values; wtf?
1110 	 */
1111 	lineno = 0;
1112 
1113 	for (;;) {
1114 		ret = yylex();
1115 		if (ret == 0 || ret == NEWLINE) {
1116 			if (mountpoint != NULL) {
1117 				//log_debugx("adding map for %s", mountpoint);
1118 				node_new_map(root, mountpoint, options, map,
1119 				    master, lineno);
1120 			}
1121 			if (ret == 0) {
1122 				break;
1123 			} else {
1124 				mountpoint = map = options = NULL;
1125 				continue;
1126 			}
1127 		}
1128 		if (mountpoint == NULL) {
1129 			mountpoint = checked_strdup(yytext);
1130 		} else if (map == NULL) {
1131 			map = checked_strdup(yytext);
1132 		} else if (options == NULL) {
1133 			/*
1134 			 * +1 to skip leading "-".
1135 			 */
1136 			options = checked_strdup(yytext + 1);
1137 		} else {
1138 			log_errx(1, "too many arguments at %s, line %d",
1139 			    master, lineno);
1140 		}
1141 	}
1142 }
1143 
1144 void
parse_master(struct node * root,const char * master)1145 parse_master(struct node *root, const char *master)
1146 {
1147 
1148 	log_debugx("parsing auto_master file at \"%s\"", master);
1149 
1150 	yyin = fopen(master, "r");
1151 	if (yyin == NULL)
1152 		err(1, "unable to open %s", master);
1153 
1154 	parse_master_yyin(root, master);
1155 
1156 	fclose(yyin);
1157 	yyin = NULL;
1158 
1159 	log_debugx("done parsing \"%s\"", master);
1160 
1161 	node_expand_includes(root, true);
1162 	node_expand_direct_maps(root);
1163 }
1164 
1165 /*
1166  * Two things daemon(3) does, that we actually also want to do
1167  * when running in foreground, is closing the stdin and chdiring
1168  * to "/".  This is what we do here.
1169  */
1170 void
lesser_daemon(void)1171 lesser_daemon(void)
1172 {
1173 	int error, fd;
1174 
1175 	error = chdir("/");
1176 	if (error != 0)
1177 		log_warn("chdir");
1178 
1179 	fd = open(_PATH_DEVNULL, O_RDWR, 0);
1180 	if (fd < 0) {
1181 		log_warn("cannot open %s", _PATH_DEVNULL);
1182 		return;
1183 	}
1184 
1185 	error = dup2(fd, STDIN_FILENO);
1186 	if (error != 0)
1187 		log_warn("dup2");
1188 
1189 	error = close(fd);
1190 	if (error != 0) {
1191 		/* Bloody hell. */
1192 		log_warn("close");
1193 	}
1194 }
1195 
1196 int
main(int argc,char ** argv)1197 main(int argc, char **argv)
1198 {
1199 	char *cmdname;
1200 
1201 	if (argv[0] == NULL)
1202 		log_errx(1, "NULL command name");
1203 
1204 	cmdname = basename(argv[0]);
1205 
1206 	if (strcmp(cmdname, "automount") == 0)
1207 		return main_automount(argc, argv);
1208 	else if (strcmp(cmdname, "automountd") == 0)
1209 		return main_automountd(argc, argv);
1210 	else if (strcmp(cmdname, "autounmountd") == 0)
1211 		return main_autounmountd(argc, argv);
1212 	else
1213 		log_errx(1, "binary name should be either \"automount\", "
1214 		    "\"automountd\", or \"autounmountd\"");
1215 }
1216