xref: /freebsd/usr.sbin/makefs/mtree.c (revision 5dae51da3da0cc94d17bd67b308fad304ebec7e0)
1 /*-
2  * Copyright (c) 2011 Marcel Moolenaar
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17  * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24  */
25 
26 #include <sys/cdefs.h>
27 __FBSDID("$FreeBSD$");
28 
29 #include <sys/param.h>
30 #include <sys/queue.h>
31 #include <sys/sbuf.h>
32 #include <sys/stat.h>
33 #include <sys/types.h>
34 #include <assert.h>
35 #include <errno.h>
36 #include <fcntl.h>
37 #include <grp.h>
38 #include <inttypes.h>
39 #include <pwd.h>
40 #include <stdarg.h>
41 #include <stdbool.h>
42 #include <stddef.h>
43 #include <stdio.h>
44 #include <stdlib.h>
45 #include <string.h>
46 #include <strings.h>
47 #include <time.h>
48 #include <unistd.h>
49 
50 #include "makefs.h"
51 
52 #ifndef ENOATTR
53 #define	ENOATTR	ENOMSG
54 #endif
55 
56 #define	IS_DOT(nm)	((nm)[0] == '.' && (nm)[1] == '\0')
57 #define	IS_DOTDOT(nm)	((nm)[0] == '.' && (nm)[1] == '.' && (nm)[2] == '\0')
58 
59 struct mtree_fileinfo {
60 	SLIST_ENTRY(mtree_fileinfo) next;
61 	FILE *fp;
62 	const char *name;
63 	u_int line;
64 };
65 
66 /* Global state used while parsing. */
67 static SLIST_HEAD(, mtree_fileinfo) mtree_fileinfo =
68     SLIST_HEAD_INITIALIZER(mtree_fileinfo);
69 static fsnode *mtree_root;
70 static fsnode *mtree_current;
71 static fsnode mtree_global;
72 static fsinode mtree_global_inode;
73 static u_int errors, warnings;
74 
75 static void mtree_error(const char *, ...) __printflike(1, 2);
76 static void mtree_warning(const char *, ...) __printflike(1, 2);
77 
78 static int
79 mtree_file_push(const char *name, FILE *fp)
80 {
81 	struct mtree_fileinfo *fi;
82 
83 	fi = malloc(sizeof(*fi));
84 	if (fi == NULL)
85 		return (ENOMEM);
86 
87 	if (strcmp(name, "-") == 0)
88 		fi->name = strdup("(stdin)");
89 	else
90 		fi->name = strdup(name);
91 	if (fi->name == NULL) {
92 		free(fi);
93 		return (ENOMEM);
94 	}
95 
96 	fi->fp = fp;
97 	fi->line = 0;
98 
99 	SLIST_INSERT_HEAD(&mtree_fileinfo, fi, next);
100 	return (0);
101 }
102 
103 static void
104 mtree_print(const char *msgtype, const char *fmt, va_list ap)
105 {
106 	struct mtree_fileinfo *fi;
107 
108 	if (msgtype != NULL) {
109 		fi = SLIST_FIRST(&mtree_fileinfo);
110 		if (fi != NULL)
111 			fprintf(stderr, "%s:%u: ", fi->name, fi->line);
112 		fprintf(stderr, "%s: ", msgtype);
113 	}
114 	vfprintf(stderr, fmt, ap);
115 }
116 
117 static void
118 mtree_error(const char *fmt, ...)
119 {
120 	va_list ap;
121 
122 	va_start(ap, fmt);
123 	mtree_print("error", fmt, ap);
124 	va_end(ap);
125 
126 	errors++;
127 	fputc('\n', stderr);
128 }
129 
130 static void
131 mtree_warning(const char *fmt, ...)
132 {
133 	va_list ap;
134 
135 	va_start(ap, fmt);
136 	mtree_print("warning", fmt, ap);
137 	va_end(ap);
138 
139 	warnings++;
140 	fputc('\n', stderr);
141 }
142 
143 #ifndef MAKEFS_MAX_TREE_DEPTH
144 # define MAKEFS_MAX_TREE_DEPTH (MAXPATHLEN/2)
145 #endif
146 
147 /* construct path to node->name */
148 static char *
149 mtree_file_path(fsnode *node)
150 {
151 	fsnode *pnode;
152 	struct sbuf *sb;
153 	char *res, *rp[MAKEFS_MAX_TREE_DEPTH];
154 	int depth;
155 
156 	depth = 0;
157 	rp[depth] = node->name;
158 	for (pnode = node->parent; pnode && depth < MAKEFS_MAX_TREE_DEPTH - 1;
159 	     pnode = pnode->parent) {
160 		if (strcmp(pnode->name, ".") == 0)
161 			break;
162 		rp[++depth] = pnode->name;
163 	}
164 
165 	sb = sbuf_new_auto();
166 	if (sb == NULL) {
167 		errno = ENOMEM;
168 		return (NULL);
169 	}
170 	while (depth > 0) {
171 		sbuf_cat(sb, rp[depth--]);
172 		sbuf_putc(sb, '/');
173 	}
174 	sbuf_cat(sb, rp[depth]);
175 	sbuf_finish(sb);
176 	res = strdup(sbuf_data(sb));
177 	sbuf_delete(sb);
178 	if (res == NULL)
179 		errno = ENOMEM;
180 	return res;
181 
182 }
183 
184 /* mtree_resolve() sets errno to indicate why NULL was returned. */
185 static char *
186 mtree_resolve(const char *spec, int *istemp)
187 {
188 	struct sbuf *sb;
189 	char *res, *var = NULL;
190 	const char *base, *p, *v;
191 	size_t len;
192 	int c, error, quoted, subst;
193 
194 	len = strlen(spec);
195 	if (len == 0) {
196 		errno = EINVAL;
197 		return (NULL);
198 	}
199 
200 	c = (len > 1) ? (spec[0] == spec[len - 1]) ? spec[0] : 0 : 0;
201 	*istemp = (c == '`') ? 1 : 0;
202 	subst = (c == '`' || c == '"') ? 1 : 0;
203 	quoted = (subst || c == '\'') ? 1 : 0;
204 
205 	if (!subst) {
206 		res = strdup(spec + quoted);
207 		if (res != NULL && quoted)
208 			res[len - 2] = '\0';
209 		return (res);
210 	}
211 
212 	sb = sbuf_new_auto();
213 	if (sb == NULL) {
214 		errno = ENOMEM;
215 		return (NULL);
216 	}
217 
218 	base = spec + 1;
219 	len -= 2;
220 	error = 0;
221 	while (len > 0) {
222 		p = strchr(base, '$');
223 		if (p == NULL) {
224 			sbuf_bcat(sb, base, len);
225 			base += len;
226 			len = 0;
227 			continue;
228 		}
229 		/* The following is safe. spec always starts with a quote. */
230 		if (p[-1] == '\\')
231 			p--;
232 		if (base != p) {
233 			sbuf_bcat(sb, base, p - base);
234 			len -= p - base;
235 			base = p;
236 		}
237 		if (*p == '\\') {
238 			sbuf_putc(sb, '$');
239 			base += 2;
240 			len -= 2;
241 			continue;
242 		}
243 		/* Skip the '$'. */
244 		base++;
245 		len--;
246 		/* Handle ${X} vs $X. */
247 		v = base;
248 		if (*base == '{') {
249 			p = strchr(v, '}');
250 			if (p == NULL)
251 				p = v;
252 		} else
253 			p = v;
254 		len -= (p + 1) - base;
255 		base = p + 1;
256 
257 		if (v == p) {
258 			sbuf_putc(sb, *v);
259 			continue;
260 		}
261 
262 		error = ENOMEM;
263 		var = calloc(p - v, 1);
264 		if (var == NULL)
265 			break;
266 
267 		memcpy(var, v + 1, p - v - 1);
268 		if (strcmp(var, ".CURDIR") == 0) {
269 			res = getcwd(NULL, 0);
270 			if (res == NULL)
271 				break;
272 		} else if (strcmp(var, ".PROG") == 0) {
273 			res = strdup(getprogname());
274 			if (res == NULL)
275 				break;
276 		} else {
277 			v = getenv(var);
278 			if (v != NULL) {
279 				res = strdup(v);
280 				if (res == NULL)
281 					break;
282 			} else
283 				res = NULL;
284 		}
285 		error = 0;
286 
287 		if (res != NULL) {
288 			sbuf_cat(sb, res);
289 			free(res);
290 		}
291 		free(var);
292 		var = NULL;
293 	}
294 
295 	free(var);
296 	sbuf_finish(sb);
297 	res = (error == 0) ? strdup(sbuf_data(sb)) : NULL;
298 	sbuf_delete(sb);
299 	if (res == NULL)
300 		errno = ENOMEM;
301 	return (res);
302 }
303 
304 static int
305 skip_over(FILE *fp, const char *cs)
306 {
307 	int c;
308 
309 	c = getc(fp);
310 	while (c != EOF && strchr(cs, c) != NULL)
311 		c = getc(fp);
312 	if (c != EOF) {
313 		ungetc(c, fp);
314 		return (0);
315 	}
316 	return (ferror(fp) ? errno : -1);
317 }
318 
319 static int
320 skip_to(FILE *fp, const char *cs)
321 {
322 	int c;
323 
324 	c = getc(fp);
325 	while (c != EOF && strchr(cs, c) == NULL)
326 		c = getc(fp);
327 	if (c != EOF) {
328 		ungetc(c, fp);
329 		return (0);
330 	}
331 	return (ferror(fp) ? errno : -1);
332 }
333 
334 static int
335 read_word(FILE *fp, char *buf, size_t bufsz)
336 {
337 	struct mtree_fileinfo *fi;
338 	size_t idx, qidx;
339 	int c, done, error, esc, qlvl;
340 
341 	if (bufsz == 0)
342 		return (EINVAL);
343 
344 	done = 0;
345 	esc = 0;
346 	idx = 0;
347 	qidx = -1;
348 	qlvl = 0;
349 	do {
350 		c = getc(fp);
351 		switch (c) {
352 		case EOF:
353 			buf[idx] = '\0';
354 			error = ferror(fp) ? errno : -1;
355 			if (error == -1)
356 				mtree_error("unexpected end of file");
357 			return (error);
358 		case '#':		/* comment -- skip to end of line. */
359 			if (!esc) {
360 				error = skip_to(fp, "\n");
361 				if (!error)
362 					continue;
363 			}
364 			break;
365 		case '\\':
366 			esc++;
367 			if (esc == 1)
368 				continue;
369 			break;
370 		case '`':
371 		case '\'':
372 		case '"':
373 			if (esc)
374 				break;
375 			if (qlvl == 0) {
376 				qlvl++;
377 				qidx = idx;
378 			} else if (c == buf[qidx]) {
379 				qlvl--;
380 				if (qlvl > 0) {
381 					do {
382 						qidx--;
383 					} while (buf[qidx] != '`' &&
384 					    buf[qidx] != '\'' &&
385 					    buf[qidx] != '"');
386 				} else
387 					qidx = -1;
388 			} else {
389 				qlvl++;
390 				qidx = idx;
391 			}
392 			break;
393 		case ' ':
394 		case '\t':
395 		case '\n':
396 			if (!esc && qlvl == 0) {
397 				ungetc(c, fp);
398 				c = '\0';
399 				done = 1;
400 				break;
401 			}
402 			if (c == '\n') {
403 				/*
404 				 * We going to eat the newline ourselves.
405 				 */
406 				if (qlvl > 0)
407 					mtree_warning("quoted word straddles "
408 					    "onto next line.");
409 				fi = SLIST_FIRST(&mtree_fileinfo);
410 				fi->line++;
411 			}
412 			break;
413 		case 'a':
414 			if (esc)
415 				c = '\a';
416 			break;
417 		case 'b':
418 			if (esc)
419 				c = '\b';
420 			break;
421 		case 'f':
422 			if (esc)
423 				c = '\f';
424 			break;
425 		case 'n':
426 			if (esc)
427 				c = '\n';
428 			break;
429 		case 'r':
430 			if (esc)
431 				c = '\r';
432 			break;
433 		case 't':
434 			if (esc)
435 				c = '\t';
436 			break;
437 		case 'v':
438 			if (esc)
439 				c = '\v';
440 			break;
441 		}
442 		buf[idx++] = c;
443 		esc = 0;
444 	} while (idx < bufsz && !done);
445 
446 	if (idx >= bufsz) {
447 		mtree_error("word too long to fit buffer (max %zu characters)",
448 		    bufsz);
449 		skip_to(fp, " \t\n");
450 	}
451 	return (0);
452 }
453 
454 static fsnode *
455 create_node(const char *name, u_int type, fsnode *parent, fsnode *global)
456 {
457 	fsnode *n;
458 
459 	n = calloc(1, sizeof(*n));
460 	if (n == NULL)
461 		return (NULL);
462 
463 	n->name = strdup(name);
464 	if (n->name == NULL) {
465 		free(n);
466 		return (NULL);
467 	}
468 
469 	n->type = (type == 0) ? global->type : type;
470 	n->parent = parent;
471 
472 	n->inode = calloc(1, sizeof(*n->inode));
473 	if (n->inode == NULL) {
474 		free(n->name);
475 		free(n);
476 		return (NULL);
477 	}
478 
479 	/* Assign global options/defaults. */
480 	bcopy(global->inode, n->inode, sizeof(*n->inode));
481 	n->inode->st.st_mode = (n->inode->st.st_mode & ~S_IFMT) | n->type;
482 
483 	if (n->type == S_IFLNK)
484 		n->symlink = global->symlink;
485 	else if (n->type == S_IFREG)
486 		n->contents = global->contents;
487 
488 	return (n);
489 }
490 
491 static void
492 destroy_node(fsnode *n)
493 {
494 
495 	assert(n != NULL);
496 	assert(n->name != NULL);
497 	assert(n->inode != NULL);
498 
499 	free(n->inode);
500 	free(n->name);
501 	free(n);
502 }
503 
504 static int
505 read_number(const char *tok, u_int base, intmax_t *res, intmax_t min,
506     intmax_t max)
507 {
508 	char *end;
509 	intmax_t val;
510 
511 	val = strtoimax(tok, &end, base);
512 	if (end == tok || end[0] != '\0')
513 		return (EINVAL);
514 	if (val < min || val > max)
515 		return (EDOM);
516 	*res = val;
517 	return (0);
518 }
519 
520 static int
521 read_mtree_keywords(FILE *fp, fsnode *node)
522 {
523 	char keyword[PATH_MAX];
524 	char *name, *p, *value;
525 	gid_t gid;
526 	uid_t uid;
527 	struct stat *st, sb;
528 	intmax_t num;
529 	u_long flset, flclr;
530 	int error, istemp, type;
531 
532 	st = &node->inode->st;
533 	do {
534 		error = skip_over(fp, " \t");
535 		if (error)
536 			break;
537 
538 		error = read_word(fp, keyword, sizeof(keyword));
539 		if (error)
540 			break;
541 
542 		if (keyword[0] == '\0')
543 			break;
544 
545 		value = strchr(keyword, '=');
546 		if (value != NULL)
547 			*value++ = '\0';
548 
549 		/*
550 		 * We use EINVAL, ENOATTR, ENOSYS and ENXIO to signal
551 		 * certain conditions:
552 		 *   EINVAL -	Value provided for a keyword that does
553 		 *		not take a value. The value is ignored.
554 		 *   ENOATTR -	Value missing for a keyword that needs
555 		 *		a value. The keyword is ignored.
556 		 *   ENOSYS -	Unsupported keyword encountered. The
557 		 *		keyword is ignored.
558 		 *   ENXIO -	Value provided for a keyword that does
559 		 *		not take a value. The value is ignored.
560 		 */
561 		switch (keyword[0]) {
562 		case 'c':
563 			if (strcmp(keyword, "contents") == 0) {
564 				if (value == NULL) {
565 					error = ENOATTR;
566 					break;
567 				}
568 				node->contents = strdup(value);
569 			} else
570 				error = ENOSYS;
571 			break;
572 		case 'f':
573 			if (strcmp(keyword, "flags") == 0) {
574 				if (value == NULL) {
575 					error = ENOATTR;
576 					break;
577 				}
578 				flset = flclr = 0;
579 				if (!strtofflags(&value, &flset, &flclr)) {
580 					st->st_flags &= ~flclr;
581 					st->st_flags |= flset;
582 				} else
583 					error = errno;
584 			} else
585 				error = ENOSYS;
586 			break;
587 		case 'g':
588 			if (strcmp(keyword, "gid") == 0) {
589 				if (value == NULL) {
590 					error = ENOATTR;
591 					break;
592 				}
593 				error = read_number(value, 10, &num,
594 				    0, UINT_MAX);
595 				if (!error)
596 					st->st_gid = num;
597 			} else if (strcmp(keyword, "gname") == 0) {
598 				if (value == NULL) {
599 					error = ENOATTR;
600 					break;
601 				}
602 				if (gid_from_group(value, &gid) == 0)
603 					st->st_gid = gid;
604 				else
605 					error = EINVAL;
606 			} else
607 				error = ENOSYS;
608 			break;
609 		case 'l':
610 			if (strcmp(keyword, "link") == 0) {
611 				if (value == NULL) {
612 					error = ENOATTR;
613 					break;
614 				}
615 				node->symlink = strdup(value);
616 			} else
617 				error = ENOSYS;
618 			break;
619 		case 'm':
620 			if (strcmp(keyword, "mode") == 0) {
621 				if (value == NULL) {
622 					error = ENOATTR;
623 					break;
624 				}
625 				if (value[0] >= '0' && value[0] <= '9') {
626 					error = read_number(value, 8, &num,
627 					    0, 07777);
628 					if (!error) {
629 						st->st_mode &= S_IFMT;
630 						st->st_mode |= num;
631 					}
632 				} else {
633 					/* Symbolic mode not supported. */
634 					error = EINVAL;
635 					break;
636 				}
637 			} else
638 				error = ENOSYS;
639 			break;
640 		case 'o':
641 			if (strcmp(keyword, "optional") == 0) {
642 				if (value != NULL)
643 					error = ENXIO;
644 				node->flags |= FSNODE_F_OPTIONAL;
645 			} else
646 				error = ENOSYS;
647 			break;
648 		case 's':
649 			if (strcmp(keyword, "size") == 0) {
650 				if (value == NULL) {
651 					error = ENOATTR;
652 					break;
653 				}
654 				error = read_number(value, 10, &num,
655 				    0, INTMAX_MAX);
656 				if (!error)
657 					st->st_size = num;
658 			} else
659 				error = ENOSYS;
660 			break;
661 		case 't':
662 			if (strcmp(keyword, "time") == 0) {
663 				if (value == NULL) {
664 					error = ENOATTR;
665 					break;
666 				}
667 				p = strchr(value, '.');
668 				if (p != NULL)
669 					*p++ = '\0';
670 				error = read_number(value, 10, &num, 0,
671 				    INTMAX_MAX);
672 				if (error)
673 					break;
674 				st->st_atime = num;
675 				st->st_ctime = num;
676 				st->st_mtime = num;
677 				if (p == NULL)
678 					break;
679 				error = read_number(p, 10, &num, 0,
680 				    INTMAX_MAX);
681 				if (error)
682 					break;
683 				if (num != 0)
684 					error = EINVAL;
685 			} else if (strcmp(keyword, "type") == 0) {
686 				if (value == NULL) {
687 					error = ENOATTR;
688 					break;
689 				}
690 				if (strcmp(value, "dir") == 0)
691 					node->type = S_IFDIR;
692 				else if (strcmp(value, "file") == 0)
693 					node->type = S_IFREG;
694 				else if (strcmp(value, "link") == 0)
695 					node->type = S_IFLNK;
696 				else
697 					error = EINVAL;
698 			} else
699 				error = ENOSYS;
700 			break;
701 		case 'u':
702 			if (strcmp(keyword, "uid") == 0) {
703 				if (value == NULL) {
704 					error = ENOATTR;
705 					break;
706 				}
707 				error = read_number(value, 10, &num,
708 				    0, UINT_MAX);
709 				if (!error)
710 					st->st_uid = num;
711 			} else if (strcmp(keyword, "uname") == 0) {
712 				if (value == NULL) {
713 					error = ENOATTR;
714 					break;
715 				}
716 				if (uid_from_user(value, &uid) == 0)
717 					st->st_uid = uid;
718 				else
719 					error = EINVAL;
720 			} else
721 				error = ENOSYS;
722 			break;
723 		default:
724 			error = ENOSYS;
725 			break;
726 		}
727 
728 		switch (error) {
729 		case EINVAL:
730 			mtree_error("%s: invalid value '%s'", keyword, value);
731 			break;
732 		case ENOATTR:
733 			mtree_error("%s: keyword needs a value", keyword);
734 			break;
735 		case ENOSYS:
736 			mtree_warning("%s: unsupported keyword", keyword);
737 			break;
738 		case ENXIO:
739 			mtree_error("%s: keyword does not take a value",
740 			    keyword);
741 			break;
742 		}
743 	} while (1);
744 
745 	if (error)
746 		return (error);
747 
748 	st->st_mode = (st->st_mode & ~S_IFMT) | node->type;
749 
750 	/* Nothing more to do for the global defaults. */
751 	if (node->name == NULL)
752 		return (0);
753 
754 	/*
755 	 * Be intelligent about the file type.
756 	 */
757 	if (node->contents != NULL) {
758 		if (node->symlink != NULL) {
759 			mtree_error("%s: both link and contents keywords "
760 			    "defined", node->name);
761 			return (0);
762 		}
763 		type = S_IFREG;
764 	} else if (node->type != 0) {
765 		type = node->type;
766 		if (type == S_IFREG) {
767 			/* the named path is the default contents */
768 			node->contents = mtree_file_path(node);
769 		}
770 	} else
771 		type = (node->symlink != NULL) ? S_IFLNK : S_IFDIR;
772 
773 	if (node->type == 0)
774 		node->type = type;
775 
776 	if (node->type != type) {
777 		mtree_error("%s: file type and defined keywords to not match",
778 		    node->name);
779 		return (0);
780 	}
781 
782 	st->st_mode = (st->st_mode & ~S_IFMT) | node->type;
783 
784 	if (node->contents == NULL)
785 		return (0);
786 
787 	name = mtree_resolve(node->contents, &istemp);
788 	if (name == NULL)
789 		return (errno);
790 
791 	if (stat(name, &sb) != 0) {
792 		mtree_error("%s: contents file '%s' not found", node->name,
793 		    name);
794 		free(name);
795 		return (0);
796 	}
797 
798 	/*
799          * Check for hardlinks. If the contents key is used, then the check
800          * will only trigger if the contents file is a link even if it is used
801          * by more than one file
802 	 */
803 	if (sb.st_nlink > 1) {
804 		fsinode *curino;
805 
806 		st->st_ino = sb.st_ino;
807 		st->st_dev = sb.st_dev;
808 		curino = link_check(node->inode);
809 		if (curino != NULL) {
810 			free(node->inode);
811 			node->inode = curino;
812 			node->inode->nlink++;
813 		}
814 	}
815 
816 	free(node->contents);
817 	node->contents = name;
818 	st->st_size = sb.st_size;
819 	return (0);
820 }
821 
822 static int
823 read_mtree_command(FILE *fp)
824 {
825 	char cmd[10];
826 	int error;
827 
828 	error = read_word(fp, cmd, sizeof(cmd));
829 	if (error)
830 		goto out;
831 
832 	error = read_mtree_keywords(fp, &mtree_global);
833 
834  out:
835 	skip_to(fp, "\n");
836 	(void)getc(fp);
837 	return (error);
838 }
839 
840 static int
841 read_mtree_spec1(FILE *fp, bool def, const char *name)
842 {
843 	fsnode *last, *node, *parent;
844 	u_int type;
845 	int error;
846 
847 	assert(name[0] != '\0');
848 
849 	/*
850 	 * Treat '..' specially, because it only changes our current
851 	 * directory. We don't create a node for it. We simply ignore
852 	 * any keywords that may appear on the line as well.
853 	 * Going up a directory is a little non-obvious. A directory
854 	 * node has a corresponding '.' child. The parent of '.' is
855 	 * not the '.' node of the parent directory, but the directory
856 	 * node within the parent to which the child relates. However,
857 	 * going up a directory means we need to find the '.' node to
858 	 * which the directoy node is linked.  This we can do via the
859 	 * first * pointer, because '.' is always the first entry in a
860 	 * directory.
861 	 */
862 	if (IS_DOTDOT(name)) {
863 		/* This deals with NULL pointers as well. */
864 		if (mtree_current == mtree_root) {
865 			mtree_warning("ignoring .. in root directory");
866 			return (0);
867 		}
868 
869 		node = mtree_current;
870 
871 		assert(node != NULL);
872 		assert(IS_DOT(node->name));
873 		assert(node->first == node);
874 
875 		/* Get the corresponding directory node in the parent. */
876 		node = mtree_current->parent;
877 
878 		assert(node != NULL);
879 		assert(!IS_DOT(node->name));
880 
881 		node = node->first;
882 
883 		assert(node != NULL);
884 		assert(IS_DOT(node->name));
885 		assert(node->first == node);
886 
887 		mtree_current = node;
888 		return (0);
889 	}
890 
891 	/*
892 	 * If we don't have a current directory and the first specification
893 	 * (either implicit or defined) is not '.', then we need to create
894 	 * a '.' node first (using a recursive call).
895 	 */
896 	if (!IS_DOT(name) && mtree_current == NULL) {
897 		error = read_mtree_spec1(fp, false, ".");
898 		if (error)
899 			return (error);
900 	}
901 
902 	/*
903 	 * Lookup the name in the current directory (if we have a current
904 	 * directory) to make sure we do not create multiple nodes for the
905 	 * same component. For non-definitions, if we find a node with the
906 	 * same name, simply change the current directory. For definitions
907 	 * more happens.
908 	 */
909 	last = NULL;
910 	node = mtree_current;
911 	while (node != NULL) {
912 		assert(node->first == mtree_current);
913 
914 		if (strcmp(name, node->name) == 0) {
915 			if (def == true) {
916 				if (!dupsok)
917 					mtree_error(
918 					    "duplicate definition of %s",
919 					    name);
920 				else
921 					mtree_warning(
922 					    "duplicate definition of %s",
923 					    name);
924 				return (0);
925 			}
926 
927 			if (node->type != S_IFDIR) {
928 				mtree_error("%s is not a directory", name);
929 				return (0);
930 			}
931 
932 			assert(!IS_DOT(name));
933 
934 			node = node->child;
935 
936 			assert(node != NULL);
937 			assert(IS_DOT(node->name));
938 
939 			mtree_current = node;
940 			return (0);
941 		}
942 
943 		last = node;
944 		node = last->next;
945 	}
946 
947 	parent = (mtree_current != NULL) ? mtree_current->parent : NULL;
948 	type = (def == false || IS_DOT(name)) ? S_IFDIR : 0;
949 	node = create_node(name, type, parent, &mtree_global);
950 	if (node == NULL)
951 		return (ENOMEM);
952 
953 	if (def == true) {
954 		error = read_mtree_keywords(fp, node);
955 		if (error) {
956 			destroy_node(node);
957 			return (error);
958 		}
959 	}
960 
961 	node->first = (mtree_current != NULL) ? mtree_current : node;
962 
963 	if (last != NULL)
964 		last->next = node;
965 
966 	if (node->type != S_IFDIR)
967 		return (0);
968 
969 	if (!IS_DOT(node->name)) {
970 		parent = node;
971 		node = create_node(".", S_IFDIR, parent, parent);
972 		if (node == NULL) {
973 			last->next = NULL;
974 			destroy_node(parent);
975 			return (ENOMEM);
976 		}
977 		parent->child = node;
978 		node->first = node;
979 	}
980 
981 	assert(node != NULL);
982 	assert(IS_DOT(node->name));
983 	assert(node->first == node);
984 
985 	mtree_current = node;
986 	if (mtree_root == NULL)
987 		mtree_root = node;
988 
989 	return (0);
990 }
991 
992 static int
993 read_mtree_spec(FILE *fp)
994 {
995 	char pathspec[PATH_MAX];
996 	char *cp;
997 	int error;
998 
999 	error = read_word(fp, pathspec, sizeof(pathspec));
1000 	if (error)
1001 		goto out;
1002 
1003 	cp = strchr(pathspec, '/');
1004 	if (cp != NULL) {
1005 		/* Absolute pathname */
1006 		mtree_current = mtree_root;
1007 
1008 		do {
1009 			*cp++ = '\0';
1010 
1011 			/* Disallow '..' as a component. */
1012 			if (IS_DOTDOT(pathspec)) {
1013 				mtree_error("absolute path cannot contain "
1014 				    ".. component");
1015 				goto out;
1016 			}
1017 
1018 			/* Ignore multiple adjacent slashes and '.'. */
1019 			if (pathspec[0] != '\0' && !IS_DOT(pathspec))
1020 				error = read_mtree_spec1(fp, false, pathspec);
1021 			memmove(pathspec, cp, strlen(cp) + 1);
1022 			cp = strchr(pathspec, '/');
1023 		} while (!error && cp != NULL);
1024 
1025 		/* Disallow '.' and '..' as the last component. */
1026 		if (!error && (IS_DOT(pathspec) || IS_DOTDOT(pathspec))) {
1027 			mtree_error("absolute path cannot contain . or .. "
1028 			    "components");
1029 			goto out;
1030 		}
1031 	}
1032 
1033 	/* Ignore absolute specfications that end with a slash. */
1034 	if (!error && pathspec[0] != '\0')
1035 		error = read_mtree_spec1(fp, true, pathspec);
1036 
1037  out:
1038 	skip_to(fp, "\n");
1039 	(void)getc(fp);
1040 	return (error);
1041 }
1042 
1043 fsnode *
1044 read_mtree(const char *fname, fsnode *node)
1045 {
1046 	struct mtree_fileinfo *fi;
1047 	FILE *fp;
1048 	int c, error;
1049 
1050 	/* We do not yet support nesting... */
1051 	assert(node == NULL);
1052 
1053 	if (strcmp(fname, "-") == 0)
1054 		fp = stdin;
1055 	else {
1056 		fp = fopen(fname, "r");
1057 		if (fp == NULL)
1058 			err(1, "Can't open `%s'", fname);
1059 	}
1060 
1061 	error = mtree_file_push(fname, fp);
1062 	if (error)
1063 		goto out;
1064 
1065 	bzero(&mtree_global, sizeof(mtree_global));
1066 	bzero(&mtree_global_inode, sizeof(mtree_global_inode));
1067 	mtree_global.inode = &mtree_global_inode;
1068 	mtree_global_inode.nlink = 1;
1069 	mtree_global_inode.st.st_nlink = 1;
1070 	mtree_global_inode.st.st_atime = mtree_global_inode.st.st_ctime =
1071 	    mtree_global_inode.st.st_mtime = time(NULL);
1072 	errors = warnings = 0;
1073 
1074 	setgroupent(1);
1075 	setpassent(1);
1076 
1077 	mtree_root = node;
1078 	mtree_current = node;
1079 	do {
1080 		/* Start of a new line... */
1081 		fi = SLIST_FIRST(&mtree_fileinfo);
1082 		fi->line++;
1083 
1084 		error = skip_over(fp, " \t");
1085 		if (error)
1086 			break;
1087 
1088 		c = getc(fp);
1089 		if (c == EOF) {
1090 			error = ferror(fp) ? errno : -1;
1091 			break;
1092 		}
1093 
1094 		switch (c) {
1095 		case '\n':		/* empty line */
1096 			error = 0;
1097 			break;
1098 		case '#':		/* comment -- skip to end of line. */
1099 			error = skip_to(fp, "\n");
1100 			if (!error)
1101 				(void)getc(fp);
1102 			break;
1103 		case '/':		/* special commands */
1104 			error = read_mtree_command(fp);
1105 			break;
1106 		default:		/* specification */
1107 			ungetc(c, fp);
1108 			error = read_mtree_spec(fp);
1109 			break;
1110 		}
1111 	} while (!error);
1112 
1113 	endpwent();
1114 	endgrent();
1115 
1116 	if (error <= 0 && (errors || warnings)) {
1117 		warnx("%u error(s) and %u warning(s) in mtree manifest",
1118 		    errors, warnings);
1119 		if (errors)
1120 			exit(1);
1121 	}
1122 
1123  out:
1124 	if (error > 0)
1125 		errc(1, error, "Error reading mtree file");
1126 
1127 	if (fp != stdin)
1128 		fclose(fp);
1129 
1130 	if (mtree_root != NULL)
1131 		return (mtree_root);
1132 
1133 	/* Handle empty specifications. */
1134 	node = create_node(".", S_IFDIR, NULL, &mtree_global);
1135 	node->first = node;
1136 	return (node);
1137 }
1138