xref: /illumos-gate/usr/src/cmd/backup/restore/utilities.c (revision d9529689937cca41f8af4b28094109ebe366870d)
1 /*
2  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
3  * Use is subject to license terms.
4  */
5 
6 /*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
7 /*	  All Rights Reserved	*/
8 
9 /*
10  * Copyright (c) 1983 Regents of the University of California.
11  * All rights reserved.  The Berkeley software License Agreement
12  * specifies the terms and conditions for redistribution.
13  */
14 
15 #include "restore.h"
16 #include <ctype.h>
17 #include <errno.h>
18 #include <syslog.h>
19 #include <limits.h>
20 /* LINTED: this file really is necessary */
21 #include <euc.h>
22 #include <widec.h>
23 
24 /*
25  * Insure that all the components of a pathname exist. Note that
26  * lookupname() and addentry() both expect complex names as
27  * input arguments, so a double NULL needs to be added to each name.
28  */
29 void
pathcheck(char * name)30 pathcheck(char *name)
31 {
32 	char *cp, save;
33 	struct entry *ep;
34 	char *start;
35 
36 	start = strchr(name, '/');
37 	if (start == 0)
38 		return;
39 	for (cp = start; *cp != '\0'; cp++) {
40 		if (*cp != '/')
41 			continue;
42 		*cp = '\0';
43 		save = *(cp+1);
44 		*(cp+1) = '\0';
45 		ep = lookupname(name);
46 		if (ep == NIL) {
47 			ep = addentry(name, psearch(name), NODE);
48 			newnode(ep);
49 		}
50 		/* LINTED: result fits in a short */
51 		ep->e_flags |= NEW|KEEP;
52 		*cp = '/';
53 		*(cp+1) = save;
54 	}
55 }
56 
57 /*
58  * Change a name to a unique temporary name.
59  */
60 void
mktempname(struct entry * ep)61 mktempname(struct entry *ep)
62 {
63 	char *newname;
64 
65 	if (ep->e_flags & TMPNAME)
66 		badentry(ep, gettext("mktempname: called with TMPNAME"));
67 	/* LINTED: result fits in a short */
68 	ep->e_flags |= TMPNAME;
69 	newname = savename(gentempname(ep));
70 	renameit(myname(ep), newname);
71 	freename(ep->e_name);
72 	ep->e_name = newname;
73 	/* LINTED: savename guarantees strlen will fit */
74 	ep->e_namlen = strlen(ep->e_name);
75 }
76 
77 /*
78  * Generate a temporary name for an entry.
79  */
80 char *
gentempname(struct entry * ep)81 gentempname(struct entry *ep)
82 {
83 	static char name[MAXPATHLEN];
84 	struct entry *np;
85 	long i = 0;
86 
87 	for (np = lookupino(ep->e_ino); np != NIL && np != ep; np = np->e_links)
88 		i++;
89 	if (np == NIL)
90 		badentry(ep, gettext("not on ino list"));
91 	(void) snprintf(name, sizeof (name), "%s%ld%lu", TMPHDR, i, ep->e_ino);
92 	return (name);
93 }
94 
95 /*
96  * Rename a file or directory.
97  */
98 void
renameit(char * fp,char * tp)99 renameit(char *fp, char *tp)
100 {
101 	int fromfd, tofd;
102 	char *from, *to;
103 	char tobuf[MAXPATHLEN];
104 	char *pathend;
105 
106 	resolve(fp, &fromfd, &from);
107 	/*
108 	 * The to pointer argument is assumed to be either a fully
109 	 * specified path (starting with "./") or a simple temporary
110 	 * file name (starting with TMPHDR).  If passed a simple temp
111 	 * file name, we need to set up the descriptors explicitly.
112 	 */
113 	if (strncmp(tp, TMPHDR, sizeof (TMPHDR) - 1) == 0) {
114 		tofd = fromfd;
115 		if ((pathend = strrchr(from, '/')) != NULL) {
116 			strncpy(tobuf, from, pathend - from + 1);
117 			tobuf[pathend - from + 1] = '\0';
118 			strlcat(tobuf, tp, sizeof (tobuf));
119 			to = tobuf;
120 		} else {
121 			to = tp;
122 		}
123 	} else
124 		resolve(tp, &tofd, &to);
125 	if (renameat(fromfd, from, tofd, to) < 0) {
126 		int saverr = errno;
127 		(void) fprintf(stderr,
128 		    gettext("Warning: cannot rename %s to %s: %s\n"),
129 		    from, to, strerror(saverr));
130 		(void) fflush(stderr);
131 	} else {
132 		vprintf(stdout, gettext("rename %s to %s\n"), from, to);
133 	}
134 	if (fromfd != AT_FDCWD) (void) close(fromfd);
135 	if (tofd != AT_FDCWD) (void) close(tofd);
136 }
137 
138 /*
139  * Create a new node (directory). Note that, because we have no
140  * mkdirat() function, fchdir() must be used set up the appropriate
141  * name space context prior to the call to mkdir() if we are
142  * operating in attribute space.
143  */
144 void
newnode(struct entry * np)145 newnode(struct entry *np)
146 {
147 	char *cp;
148 	int dfd;
149 
150 	if (np->e_type != NODE)
151 		badentry(np, gettext("newnode: not a node"));
152 	resolve(myname(np), &dfd, &cp);
153 	if (dfd != AT_FDCWD) {
154 		if (fchdir(dfd) < 0) {
155 			int saverr = errno;
156 			(void) fprintf(stderr,
157 			    gettext("Warning: cannot create %s: %s"),
158 			    cp, strerror(saverr));
159 			(void) fflush(stderr);
160 			(void) close(dfd);
161 			return;
162 		}
163 	}
164 	if (mkdir(cp, 0777) < 0) {
165 		int saverr = errno;
166 		/* LINTED: result fits in a short */
167 		np->e_flags |= EXISTED;
168 		(void) fprintf(stderr, gettext("Warning: "));
169 		(void) fflush(stderr);
170 		(void) fprintf(stderr, "%s: %s\n", cp, strerror(saverr));
171 	} else {
172 		vprintf(stdout, gettext("Make node %s\n"), cp);
173 	}
174 	if (dfd != AT_FDCWD) {
175 		fchdir(savepwd);
176 		(void) close(dfd);
177 	}
178 }
179 
180 /*
181  * Remove an old node (directory). See comment above on newnode()
182  * for explanation of fchdir() use below.
183  */
184 void
removenode(struct entry * ep)185 removenode(struct entry *ep)
186 {
187 	char *cp;
188 	int dfd;
189 
190 	if (ep->e_type != NODE)
191 		badentry(ep, gettext("removenode: not a node"));
192 	if (ep->e_entries != NIL)
193 		badentry(ep, gettext("removenode: non-empty directory"));
194 	/* LINTED: result fits in a short */
195 	ep->e_flags |= REMOVED;
196 	/* LINTED: result fits in a short */
197 	ep->e_flags &= ~TMPNAME;
198 	resolve(myname(ep), &dfd, &cp);
199 	if (dfd != AT_FDCWD) {
200 		if (fchdir(dfd) < 0) {
201 			int saverr = errno;
202 			(void) fprintf(stderr,
203 			    gettext("Warning: cannot remove %s: %s"),
204 			    cp, strerror(saverr));
205 			(void) fflush(stderr);
206 			(void) close(dfd);
207 			return;
208 		}
209 	}
210 	if (rmdir(cp) < 0) {	/* NOTE: could use unlinkat (..,REMOVEDIR) */
211 		int saverr = errno;
212 		(void) fprintf(stderr, gettext("Warning: %s: %s\n"),
213 		    cp, strerror(saverr));
214 		(void) fflush(stderr);
215 	} else {
216 		vprintf(stdout, gettext("Remove node %s\n"), cp);
217 	}
218 	if (dfd != AT_FDCWD) {
219 		(void) fchdir(savepwd);
220 		(void) close(dfd);
221 	}
222 }
223 
224 /*
225  * Remove a leaf.
226  */
227 void
removeleaf(struct entry * ep)228 removeleaf(struct entry *ep)
229 {
230 	char *cp;
231 	int dfd;
232 
233 	if (ep->e_type != LEAF)
234 		badentry(ep, gettext("removeleaf: not a leaf"));
235 	/* LINTED: result fits in a short */
236 	ep->e_flags |= REMOVED;
237 	/* LINTED: result fits in a short */
238 	ep->e_flags &= ~TMPNAME;
239 	resolve(myname(ep), &dfd, &cp);
240 	if (unlinkat(dfd, cp, 0) < 0) {
241 		int saverr = errno;
242 		(void) fprintf(stderr, gettext("Warning: %s: %s\n"),
243 		    cp, strerror(saverr));
244 		(void) fflush(stderr);
245 	} else {
246 		vprintf(stdout, gettext("Remove leaf %s\n"), cp);
247 	}
248 	if (dfd != AT_FDCWD)
249 		(void) close(dfd);
250 }
251 
252 /*
253  * Create a link.
254  *	This function assumes that the context has already been set
255  *	for the link file to be created (i.e., we have "fchdir-ed"
256  *	into attribute space already if this is an attribute link).
257  */
258 int
lf_linkit(char * existing,char * new,int type)259 lf_linkit(char *existing, char *new, int type)
260 {
261 	char linkbuf[MAXPATHLEN];
262 	struct stat64 s1[1], s2[1];
263 	char *name;
264 	int dfd, l, result;
265 
266 	resolve(existing, &dfd, &name);
267 	if (dfd == -1) {
268 		(void) fprintf(stderr, gettext(
269 		    "Warning: cannot restore %s link %s->%s\n"),
270 		    (type == SYMLINK ? "symbolic" : "hard"), new, existing);
271 		result = FAIL;
272 		goto out;
273 	}
274 	if (type == SYMLINK) {
275 		if (symlink(name, new) < 0) {
276 			/* No trailing \0 from readlink(2) */
277 			if (((l = readlink(new, linkbuf, sizeof (linkbuf)))
278 			    > 0) &&
279 			    (l == strlen(name)) &&
280 			    (strncmp(linkbuf, name, l) == 0)) {
281 				vprintf(stdout,
282 				    gettext("Symbolic link %s->%s ok\n"),
283 				    new, name);
284 				result = GOOD;
285 				goto out;
286 			} else {
287 				int saverr = errno;
288 				(void) fprintf(stderr, gettext(
289 			    "Warning: cannot create symbolic link %s->%s: %s"),
290 				    new, name, strerror(saverr));
291 				(void) fflush(stderr);
292 				result = FAIL;
293 				goto out;
294 			}
295 		}
296 	} else if (type == HARDLINK) {
297 		if (link(name, new) < 0) {
298 			int saverr = errno;
299 			if ((stat64(name, s1) == 0) &&
300 			    (stat64(new, s2) == 0) &&
301 			    (s1->st_dev == s2->st_dev) &&
302 			    (s1->st_ino == s2->st_ino)) {
303 				vprintf(stdout,
304 				    gettext("Hard link %s->%s ok\n"),
305 				    new, name);
306 				result = GOOD;
307 				goto out;
308 			} else {
309 				(void) fprintf(stderr, gettext(
310 			    "Warning: cannot create hard link %s->%s: %s\n"),
311 				    new, name, strerror(saverr));
312 				(void) fflush(stderr);
313 				result = FAIL;
314 				goto out;
315 			}
316 		}
317 	} else {
318 		panic(gettext("%s: unknown type %d\n"), "linkit", type);
319 		result = FAIL;
320 		goto out;
321 	}
322 	result = GOOD;
323 	if (type == SYMLINK)
324 		vprintf(stdout, gettext("Create symbolic link %s->%s\n"),
325 		    new, name);
326 	else
327 		vprintf(stdout, gettext("Create hard link %s->%s\n"),
328 		    new, name);
329 out:
330 	if (dfd != AT_FDCWD) {
331 		(void) close(dfd);
332 	}
333 	return (result);
334 }
335 
336 /*
337  * Find lowest-numbered inode (above "start") that needs to be extracted.
338  * Caller knows that a return value of maxino means there's nothing left.
339  */
340 ino_t
lowerbnd(ino_t start)341 lowerbnd(ino_t start)
342 {
343 	struct entry *ep;
344 
345 	for (; start < maxino; start++) {
346 		ep = lookupino(start);
347 		if (ep == NIL || ep->e_type == NODE)
348 			continue;
349 		if (ep->e_flags & (NEW|EXTRACT))
350 			return (start);
351 	}
352 	return (start);
353 }
354 
355 /*
356  * Find highest-numbered inode (below "start") that needs to be extracted.
357  */
358 ino_t
upperbnd(ino_t start)359 upperbnd(ino_t start)
360 {
361 	struct entry *ep;
362 
363 	for (; start > ROOTINO; start--) {
364 		ep = lookupino(start);
365 		if (ep == NIL || ep->e_type == NODE)
366 			continue;
367 		if (ep->e_flags & (NEW|EXTRACT))
368 			return (start);
369 	}
370 	return (start);
371 }
372 
373 /*
374  * report on a badly formed entry
375  */
376 void
badentry(struct entry * ep,char * msg)377 badentry(struct entry *ep, char *msg)
378 {
379 
380 	(void) fprintf(stderr, gettext("bad entry: %s\n"), msg);
381 	(void) fprintf(stderr, gettext("name: %s\n"), myname(ep));
382 	(void) fprintf(stderr, gettext("parent name %s\n"),
383 	    myname(ep->e_parent));
384 	if (ep->e_sibling != NIL)
385 		(void) fprintf(stderr, gettext("sibling name: %s\n"),
386 		    myname(ep->e_sibling));
387 	if (ep->e_entries != NIL)
388 		(void) fprintf(stderr, gettext("next entry name: %s\n"),
389 		    myname(ep->e_entries));
390 	if (ep->e_links != NIL)
391 		(void) fprintf(stderr, gettext("next link name: %s\n"),
392 		    myname(ep->e_links));
393 	if (ep->e_xattrs != NIL)
394 		(void) fprintf(stderr, gettext("attribute root name: %s\n"),
395 		    myname(ep->e_xattrs));
396 	if (ep->e_next != NIL)
397 		(void) fprintf(stderr, gettext("next hashchain name: %s\n"),
398 		    myname(ep->e_next));
399 	(void) fprintf(stderr, gettext("entry type: %s\n"),
400 	    ep->e_type == NODE ? gettext("NODE") : gettext("LEAF"));
401 	(void) fprintf(stderr, gettext("inode number: %lu\n"), ep->e_ino);
402 	panic(gettext("flags: %s\n"), flagvalues(ep));
403 	/* Our callers are expected to handle our returning. */
404 }
405 
406 /*
407  * Construct a string indicating the active flag bits of an entry.
408  */
409 char *
flagvalues(struct entry * ep)410 flagvalues(struct entry *ep)
411 {
412 	static char flagbuf[BUFSIZ];
413 
414 	(void) strlcpy(flagbuf, gettext("|NIL"), sizeof (flagbuf));
415 	flagbuf[0] = '\0';
416 	if (ep->e_flags & REMOVED)
417 		(void) strlcat(flagbuf, gettext("|REMOVED"), sizeof (flagbuf));
418 	if (ep->e_flags & TMPNAME)
419 		(void) strlcat(flagbuf, gettext("|TMPNAME"), sizeof (flagbuf));
420 	if (ep->e_flags & EXTRACT)
421 		(void) strlcat(flagbuf, gettext("|EXTRACT"), sizeof (flagbuf));
422 	if (ep->e_flags & NEW)
423 		(void) strlcat(flagbuf, gettext("|NEW"), sizeof (flagbuf));
424 	if (ep->e_flags & KEEP)
425 		(void) strlcat(flagbuf, gettext("|KEEP"), sizeof (flagbuf));
426 	if (ep->e_flags & EXISTED)
427 		(void) strlcat(flagbuf, gettext("|EXISTED"), sizeof (flagbuf));
428 	if (ep->e_flags & XATTR)
429 		(void) strlcat(flagbuf, gettext("|XATTR"), sizeof (flagbuf));
430 	if (ep->e_flags & XATTRROOT)
431 		(void) strlcat(flagbuf, gettext("|XATTRROOT"),
432 		    sizeof (flagbuf));
433 	return (&flagbuf[1]);
434 }
435 
436 /*
437  * Check to see if a name is on a dump tape.
438  */
439 ino_t
dirlookup(char * name)440 dirlookup(char *name)
441 {
442 	ino_t ino;
443 
444 	ino = psearch(name);
445 	if (ino == 0 || BIT(ino, dumpmap) == 0)
446 		(void) fprintf(stderr, gettext("%s is not on volume\n"), name);
447 	return (ino);
448 }
449 
450 /*
451  * Elicit a reply.
452  */
453 int
reply(char * question)454 reply(char *question)
455 {
456 	char *yesorno = gettext("yn"); /* must be two characters, "yes" first */
457 	int c;
458 
459 	do	{
460 		(void) fprintf(stderr, "%s? [%s] ", question, yesorno);
461 		(void) fflush(stderr);
462 		c = getc(terminal);
463 		while (c != '\n' && getc(terminal) != '\n') {
464 			if (ferror(terminal)) {
465 				(void) fprintf(stderr, gettext(
466 				    "Error reading response\n"));
467 				(void) fflush(stderr);
468 				return (FAIL);
469 			}
470 			if (feof(terminal))
471 				return (FAIL);
472 		}
473 		if (isupper(c))
474 			c = tolower(c);
475 	} while (c != yesorno[0] && c != yesorno[1]);
476 	if (c == yesorno[0])
477 		return (GOOD);
478 	return (FAIL);
479 }
480 
481 /*
482  * handle unexpected inconsistencies
483  */
484 /*
485  * Note that a panic w/ EOF on the tty means all panics will return...
486  */
487 #include <stdarg.h>
488 
489 /* VARARGS1 */
490 void
panic(const char * msg,...)491 panic(const char *msg, ...)
492 {
493 	va_list	args;
494 
495 	va_start(args, msg);
496 	(void) vfprintf(stderr, msg, args);
497 	va_end(args);
498 	if (reply(gettext("abort")) == GOOD) {
499 		if (reply(gettext("dump core")) == GOOD)
500 			abort();
501 		done(1);
502 	}
503 }
504 
505 /*
506  * Locale-specific version of ctime
507  */
508 char *
lctime(time_t * tp)509 lctime(time_t *tp)
510 {
511 	static char buf[256];
512 	struct tm *tm;
513 
514 	tm = localtime(tp);
515 	(void) strftime(buf, sizeof (buf), "%c\n", tm);
516 	return (buf);
517 }
518 
519 static int
statcmp(const struct stat * left,const struct stat * right)520 statcmp(const struct stat *left, const struct stat *right)
521 {
522 	int result = 1;
523 
524 	if ((left->st_dev == right->st_dev) &&
525 	    (left->st_ino == right->st_ino) &&
526 	    (left->st_mode == right->st_mode) &&
527 	    (left->st_nlink == right->st_nlink) &&
528 	    (left->st_uid == right->st_uid) &&
529 	    (left->st_gid == right->st_gid) &&
530 	    (left->st_rdev == right->st_rdev) &&
531 	    (left->st_ctim.tv_sec == right->st_ctim.tv_sec) &&
532 	    (left->st_ctim.tv_nsec == right->st_ctim.tv_nsec) &&
533 	    (left->st_mtim.tv_sec == right->st_mtim.tv_sec) &&
534 	    (left->st_mtim.tv_nsec == right->st_mtim.tv_nsec) &&
535 	    (left->st_blksize == right->st_blksize) &&
536 	    (left->st_blocks == right->st_blocks)) {
537 		result = 0;
538 	}
539 
540 	return (result);
541 }
542 
543 /*
544  * Safely open a file.
545  */
546 int
safe_open(int dfd,const char * filename,int mode,int perms)547 safe_open(int dfd, const char *filename, int mode, int perms)
548 {
549 	static int init_syslog = 1;
550 	int fd;
551 	int working_mode;
552 	int saverr;
553 	char *errtext;
554 	struct stat pre_stat, pre_lstat;
555 	struct stat post_stat, post_lstat;
556 
557 	if (init_syslog) {
558 		openlog(progname, LOG_CONS, LOG_DAEMON);
559 		init_syslog = 0;
560 	}
561 
562 	/*
563 	 * Don't want to be spoofed into trashing something we
564 	 * shouldn't, thus the following rigamarole.  If it doesn't
565 	 * exist, we create it and proceed.  Otherwise, require that
566 	 * what's there be a real file with no extraneous links and
567 	 * owned by whoever ran us.
568 	 *
569 	 * The silliness with using both lstat() and fstat() is to avoid
570 	 * race-condition games with someone replacing the file with a
571 	 * symlink after we've opened it.  If there was an flstat(),
572 	 * we wouldn't need the fstat().
573 	 *
574 	 * The initial open with the hard-coded flags is ok even if we
575 	 * are intending to open only for reading.  If it succeeds,
576 	 * then the file did not exist, and we'll synthesize an appropriate
577 	 * complaint below.  Otherwise, it does exist, so we won't be
578 	 * truncating it with the open.
579 	 */
580 	if ((fd = openat(dfd, filename,
581 	    O_WRONLY|O_CREAT|O_TRUNC|O_EXCL|O_LARGEFILE, perms)) < 0) {
582 		if (errno == EEXIST) {
583 			if (fstatat(dfd, filename, &pre_lstat,
584 			    AT_SYMLINK_NOFOLLOW) < 0) {
585 				saverr = errno;
586 				(void) close(fd);
587 				errno = saverr;
588 				return (-1);
589 			}
590 
591 			if (fstatat(dfd, filename, &pre_stat, 0) < 0) {
592 				saverr = errno;
593 				(void) close(fd);
594 				errno = saverr;
595 				return (-1);
596 			}
597 
598 			working_mode = mode & (O_WRONLY|O_RDWR|O_RDONLY);
599 			working_mode |= O_LARGEFILE;
600 
601 			if ((fd = openat(dfd, filename, working_mode)) < 0) {
602 				if (errno == ENOENT) {
603 					errtext = gettext(
604 "Unexpected condition detected: %s used to exist, but doesn't any longer\n");
605 					(void) fprintf(stderr, errtext,
606 					    filename);
607 					syslog(LOG_WARNING, errtext, filename);
608 					errno = ENOENT;
609 				}
610 				return (-1);
611 			}
612 
613 			if (fstatat(fd, NULL, &post_lstat,
614 			    AT_SYMLINK_NOFOLLOW) < 0) {
615 				saverr = errno;
616 				(void) close(fd);
617 				errno = saverr;
618 				return (-1);
619 			}
620 
621 			if (fstatat(fd, NULL, &post_stat, 0) < 0) {
622 				saverr = errno;
623 				(void) close(fd);
624 				errno = saverr;
625 				return (-1);
626 			}
627 
628 			if (statcmp(&pre_lstat, &post_lstat) != 0) {
629 				errtext = gettext(
630 "Unexpected condition detected: %s's lstat(2) information changed\n");
631 				(void) fprintf(stderr, errtext, filename);
632 				syslog(LOG_WARNING, errtext, filename);
633 				errno = EPERM;
634 				return (-1);
635 			}
636 
637 			if (statcmp(&pre_stat, &post_stat) != 0) {
638 				errtext = gettext(
639 "Unexpected condition detected: %s's stat(2) information changed\n");
640 				(void) fprintf(stderr, errtext, filename);
641 				syslog(LOG_WARNING, errtext, filename);
642 				errno = EPERM;
643 				return (-1);
644 			}
645 
646 			/*
647 			 * If inode, device, or type are wrong, bail out.
648 			 */
649 			if ((!S_ISREG(post_lstat.st_mode) ||
650 			    (post_stat.st_ino != post_lstat.st_ino) ||
651 			    (post_stat.st_dev != post_lstat.st_dev))) {
652 				errtext = gettext(
653 	    "Unexpected condition detected: %s is not a regular file\n");
654 				(void) fprintf(stderr, errtext, filename);
655 				syslog(LOG_WARNING, errtext, filename);
656 				(void) close(fd);
657 				errno = EPERM;
658 				return (-1);
659 			}
660 
661 			/*
662 			 * Bad link count implies someone's linked our
663 			 * target to something else, which we probably
664 			 * shouldn't step on.
665 			 */
666 			if (post_lstat.st_nlink != 1) {
667 				errtext = gettext(
668 	    "Unexpected condition detected: %s must have exactly one link\n");
669 				(void) fprintf(stderr, errtext, filename);
670 				syslog(LOG_WARNING, errtext, filename);
671 				(void) close(fd);
672 				errno = EPERM;
673 				return (-1);
674 			}
675 			/*
676 			 * Root might make a file, but non-root might
677 			 * need to open it.  If the permissions let us
678 			 * get this far, then let it through.
679 			 */
680 			if (post_lstat.st_uid != getuid() &&
681 			    post_lstat.st_uid != 0) {
682 				errtext = gettext(
683 "Unsupported condition detected: %s must be owned by uid %ld or 0\n");
684 				(void) fprintf(stderr, errtext, filename,
685 				    (long)getuid());
686 				syslog(LOG_WARNING, errtext, filename,
687 				    (long)getuid());
688 				(void) close(fd);
689 				errno = EPERM;
690 				return (-1);
691 			}
692 			if (mode & (O_WRONLY|O_TRUNC)) {
693 				if (ftruncate(fd, (off_t)0) < 0) {
694 					(void) fprintf(stderr,
695 					    "ftruncate(%s): %s\n",
696 					    filename, strerror(errno));
697 					(void) close(fd);
698 					return (-1);
699 				}
700 			}
701 		} else {
702 			/*
703 			 * Didn't exist, but couldn't open it.
704 			 */
705 			return (-1);
706 		}
707 	} else {
708 		/*
709 		 * If truncating open succeeded for a read-only open,
710 		 * bail out, as we really shouldn't have succeeded.
711 		 */
712 		if (mode & O_RDONLY) {
713 			/* Undo the O_CREAT */
714 			(void) unlinkat(dfd, filename, 0);
715 			(void) fprintf(stderr, "open(%s): %s\n",
716 			    filename, strerror(ENOENT));
717 			(void) close(fd);
718 			errno = ENOENT;
719 			return (-1);
720 		}
721 	}
722 
723 	return (fd);
724 }
725 
726 /*
727  * STDIO version of safe_open.  Equivalent to fopen64(...).
728  */
729 FILE *
safe_fopen(const char * filename,const char * smode,int perms)730 safe_fopen(const char *filename, const char *smode, int perms)
731 {
732 	int fd;
733 	int bmode;
734 
735 	/*
736 	 * accepts only modes  "r", "r+", and "w"
737 	 */
738 	if (smode[0] == 'r') {
739 		if (smode[1] == '\0') {
740 			bmode = O_RDONLY;
741 		} else if ((smode[1] == '+') && (smode[2] == '\0')) {
742 			bmode = O_RDWR;
743 		}
744 	} else if ((smode[0] == 'w') && (smode[1] == '\0')) {
745 		bmode = O_WRONLY;
746 	} else {
747 		(void) fprintf(stderr,
748 		    gettext("internal error: safe_fopen: invalid mode `%s'\n"),
749 		    smode);
750 		return (NULL);
751 	}
752 
753 	fd = safe_open(AT_FDCWD, filename, bmode, perms);
754 
755 	/*
756 	 * caller is expected to report error.
757 	 */
758 	if (fd >= 0)
759 		return (fdopen(fd, smode));
760 
761 	return ((FILE *)NULL);
762 }
763 
764 /*
765  * Read the contents of a directory.
766  */
767 int
mkentry(char * name,ino_t ino,struct arglist * ap)768 mkentry(char *name, ino_t ino, struct arglist *ap)
769 {
770 	struct afile *fp;
771 
772 	if (ap->base == NULL) {
773 		ap->nent = 20;
774 		ap->base = (struct afile *)calloc((unsigned)ap->nent,
775 		    sizeof (*(ap->base)));
776 		if (ap->base == NULL) {
777 			(void) fprintf(stderr,
778 			    gettext("%s: out of memory\n"), ap->cmd);
779 			return (FAIL);
780 		}
781 	}
782 	if (ap->head == NULL)
783 		ap->head = ap->last = ap->base;
784 	fp = ap->last;
785 	fp->fnum = ino;
786 	fp->fname = savename(name);
787 	fp++;
788 	if (fp == ap->head + ap->nent) {
789 		ap->base = (struct afile *)realloc((char *)ap->base,
790 		    (size_t)(2 * ap->nent * (size_t)sizeof (*(ap->base))));
791 		if (ap->base == NULL) {
792 			(void) fprintf(stderr,
793 			    gettext("%s: out of memory\n"), ap->cmd);
794 			return (FAIL);
795 		}
796 		ap->head = ap->base;
797 		fp = ap->head + ap->nent;
798 		ap->nent *= 2;
799 	}
800 	ap->last = fp;
801 	return (GOOD);
802 }
803 
804 static int gmatch(wchar_t *, wchar_t *);
805 static int addg(struct direct *, char *, char *, struct arglist *);
806 
807 /*
808  * XXX  This value is ASCII (but not language) dependent.  In
809  * ASCII, it is the DEL character (unlikely to appear in paths).
810  * If you are compiling on an EBCDIC-based machine, re-define
811  * this (0x7f is '"') to be something like 0x7 (DEL).  It's
812  * either this hack or re-write the expand() algorithm...
813  */
814 #define	DELIMCHAR	((char)0x7f)
815 
816 /*
817  * Expand a file name.
818  * "as" is the pattern to expand.
819  * "rflg" non-zero indicates that we're recursing.
820  * "ap" is where to put the results of the expansion.
821  *
822  * Our caller guarantees that "as" is at least the string ".".
823  */
824 int
expand(char * as,int rflg,struct arglist * ap)825 expand(char *as, int rflg, struct arglist *ap)
826 {
827 	int		count, size;
828 	char		dir = 0;
829 	char		*rescan = 0;
830 	RST_DIR		*dirp;
831 	char		*s, *cs;
832 	int		sindex, rindexa, lindex;
833 	struct direct	*dp;
834 	char		slash;
835 	char		*rs;
836 	char		c;
837 	wchar_t		w_fname[PATH_MAX+1];
838 	wchar_t		w_pname[PATH_MAX+1];
839 
840 	/*
841 	 * check for meta chars
842 	 */
843 	s = cs = as;
844 	slash = 0;
845 	while (*cs != '*' && *cs != '?' && *cs != '[') {
846 		if (*cs++ == 0) {
847 			if (rflg && slash)
848 				break;
849 			else
850 				return (0);
851 		} else if (*cs == '/') {
852 			slash++;
853 		}
854 	}
855 	for (;;) {
856 		if (cs == s) {
857 			s = "";
858 			break;
859 		} else if (*--cs == '/') {
860 			*cs = 0;
861 			if (s == cs)
862 				s = "/";
863 			break;
864 		}
865 	}
866 	if ((dirp = rst_opendir(s)) != NULL)
867 		dir++;
868 	count = 0;
869 	if (*cs == 0)
870 		*cs++ = DELIMCHAR;
871 	if (dir) {
872 		/*
873 		 * check for rescan
874 		 */
875 		rs = cs;
876 		do {
877 			if (*rs == '/') {
878 				rescan = rs;
879 				*rs = 0;
880 			}
881 		} while (*rs++);
882 		/* LINTED: result fits into an int */
883 		sindex = (int)(ap->last - ap->head);
884 		(void) mbstowcs(w_pname, cs, PATH_MAX);
885 		w_pname[PATH_MAX - 1] = 0;
886 		while ((dp = rst_readdir(dirp)) != NULL && dp->d_ino != 0) {
887 			if (!dflag && BIT(dp->d_ino, dumpmap) == 0)
888 				continue;
889 			if ((*dp->d_name == '.' && *cs != '.'))
890 				continue;
891 			(void) mbstowcs(w_fname, dp->d_name, PATH_MAX);
892 			w_fname[PATH_MAX - 1] = 0;
893 			if (gmatch(w_fname, w_pname)) {
894 				if (addg(dp, s, rescan, ap) < 0) {
895 					rst_closedir(dirp);
896 					return (-1);
897 				}
898 				count++;
899 			}
900 		}
901 		if (rescan) {
902 			rindexa = sindex;
903 			/* LINTED: result fits into an int */
904 			lindex = (int)(ap->last - ap->head);
905 			if (count) {
906 				count = 0;
907 				while (rindexa < lindex) {
908 					size = expand(ap->head[rindexa].fname,
909 					    1, ap);
910 					if (size < 0) {
911 						rst_closedir(dirp);
912 						return (size);
913 					}
914 					count += size;
915 					rindexa++;
916 				}
917 			}
918 			/* LINTED: lint is confused about pointer size/type */
919 			bcopy((void *)(&ap->head[lindex]),
920 			    (void *)(&ap->head[sindex]),
921 			    (size_t)((ap->last - &ap->head[rindexa])) *
922 			    sizeof (*ap->head));
923 			ap->last -= lindex - sindex;
924 			*rescan = '/';
925 		}
926 		rst_closedir(dirp);
927 	}
928 	s = as;
929 	while ((c = *s) != '\0')
930 		*s++ = (c != DELIMCHAR ? c : '/');
931 
932 	return (count);
933 }
934 
935 /*
936  * Check for a name match
937  */
938 static int
gmatch(wchar_t * s,wchar_t * p)939 gmatch(wchar_t *s, wchar_t *p)
940 {
941 	long	scc;	/* source character to text */
942 	wchar_t	c;	/* pattern character to match */
943 	char	ok;	/* [x-y] range match status */
944 	long	lc;	/* left character of [x-y] range */
945 
946 	scc = *s++;
947 	switch (c = *p++) {
948 
949 	case '[':
950 		ok = 0;
951 		lc = -1;
952 		while (c = *p++) {
953 			if (c == ']') {
954 				return (ok ? gmatch(s, p) : 0);
955 			} else if (c == '-') {
956 				wchar_t rc = *p++;
957 				/*
958 				 * Check both ends must belong to
959 				 * the same codeset.
960 				 */
961 				if (wcsetno(lc) != wcsetno(rc)) {
962 					/*
963 					 * If not, ignore the '-'
964 					 * operator and [x-y] is
965 					 * treated as if it were
966 					 * [xy].
967 					 */
968 					if (scc == lc)
969 						ok++;
970 					if (scc == (lc = rc))
971 						ok++;
972 				} else if (lc <= scc && scc <= rc)
973 					ok++;
974 			} else {
975 				lc = c;
976 				if (scc == lc)
977 					ok++;
978 			}
979 		}
980 		/* No closing bracket => failure */
981 		return (0);
982 
983 	default:
984 		if (c != scc)
985 			return (0);
986 		/*FALLTHROUGH*/
987 
988 	case '?':
989 		return (scc ? gmatch(s, p) : 0);
990 
991 	case '*':
992 		if (*p == 0)
993 			return (1);
994 		s--;
995 		while (*s) {
996 			if (gmatch(s++, p))
997 				return (1);
998 		}
999 		return (0);
1000 
1001 	case 0:
1002 		return (scc == 0);
1003 	}
1004 }
1005 
1006 /*
1007  * Construct a matched name.
1008  */
1009 static int
addg(struct direct * dp,char * as1,char * as3,struct arglist * ap)1010 addg(struct direct *dp, char *as1, char *as3, struct arglist *ap)
1011 {
1012 	char	*s1, *s2, *limit;
1013 	int	c;
1014 	char	buf[MAXPATHLEN + 1];
1015 
1016 	s2 = buf;
1017 	limit = buf + sizeof (buf) - 1;
1018 	s1 = as1;
1019 	while ((c = *s1++) != '\0' && s2 < limit) {
1020 		if (c == DELIMCHAR) {
1021 			*s2++ = '/';
1022 			break;
1023 		}
1024 		/* LINTED narrowing cast */
1025 		*s2++ = (char)c;
1026 	}
1027 	s1 = dp->d_name;
1028 	while ((*s2 = *s1++) != '\0' && s2 < limit)
1029 		s2++;
1030 	s1 = as3;
1031 	if (s1 != NULL && s2 < limit) {
1032 		*s2++ = '/';
1033 
1034 		while ((*s2++ = *++s1) != '\0' && s2 < limit) {
1035 			continue;
1036 			/*LINTED [empty loop body]*/
1037 		}
1038 	}
1039 	*s2 = '\0';
1040 	if (mkentry(buf, dp->d_ino, ap) == FAIL)
1041 		return (-1);
1042 	return (0);
1043 }
1044 
1045 
1046 /*
1047  * Resolve a "complex" pathname (as generated by myname()) into
1048  * a file descriptor and a relative path.  The file descriptor
1049  * will reference the hidden directory containing the attribute
1050  * named by the relative path.  If the provided path is not
1051  * complex, the returned file descriptor will be AT_FDCWD and rpath
1052  * will equal path.
1053  *
1054  * This function is intended to be used to transform a complex
1055  * pathname into a pair of handles that can be used to actually
1056  * manipulate the named file.  Since extended attributes have
1057  * an independant name space, a file descriptor for a directory
1058  * in the attribute name space is necessary to actually manipulate
1059  * the attribute file (via the path-relative xxxat() system calls
1060  * or a call to fchdir()).
1061  *
1062  * In the event of an error, the returned file descriptor will be
1063  * -1.  It is expected that callers will either check for this
1064  * condition directly, or attempt to use the descriptor, fail, and
1065  * generate an appropriate context-specific error message.
1066  *
1067  * This function is pretty much a no-op for "simple" (non-attribute)
1068  * paths.
1069  */
1070 void
resolve(char * path,int * fd,char ** rpath)1071 resolve(char *path, int *fd, char **rpath)
1072 {
1073 	int	tfd;
1074 
1075 	*fd = tfd = AT_FDCWD;
1076 	*rpath = path;
1077 	path = *rpath + strlen(*rpath) +1;
1078 	while (*path != '\0' &&
1079 	    (*fd = openat64(tfd, *rpath, O_RDONLY)) > 0) {
1080 		if (tfd != AT_FDCWD)
1081 			(void) close(tfd);
1082 		tfd = *fd;
1083 		*rpath = path;
1084 		path = *rpath + strlen(*rpath) +1;
1085 	}
1086 	if (*fd == AT_FDCWD)
1087 		return;
1088 	if (*fd < 0 || (*fd = openat64(tfd, ".", O_RDONLY|O_XATTR)) < 0) {
1089 		int saverr = errno;
1090 		(void) fprintf(stderr,
1091 		    gettext("Warning: cannot fully resolve %s: %s"),
1092 		    path, strerror(saverr));
1093 		(void) fflush(stderr);
1094 	}
1095 	if (tfd != AT_FDCWD) (void) close(tfd);
1096 }
1097 
1098 /*
1099  * Copy a complex pathname to another string.  Note that the
1100  * length returned by this function is the number of characters
1101  * up to (but not including) the final NULL.
1102  */
1103 int
complexcpy(char * s1,char * s2,int max)1104 complexcpy(char *s1, char *s2, int max)
1105 {
1106 	int	nullseen = 0;
1107 	int	len = 0;
1108 
1109 	while (len++ < max) {
1110 		*s1++ = *s2;
1111 		if (*s2++ == '\0') {
1112 			if (nullseen)
1113 				return (len-1);
1114 			else
1115 				nullseen = 1;
1116 		} else {
1117 			nullseen = 0;
1118 		}
1119 	}
1120 	*s1 = '\0';
1121 	if (nullseen == 0)
1122 		*--s1 = '\0';
1123 	fprintf(stderr,
1124 	    gettext("Warning: unterminated source string in complexcpy\n"));
1125 	return (max-1);
1126 }
1127