1/*-
2 * Copyright (c) 1990, 1993, 1994
3 * The Regents of the University of California. 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 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#if 0
31#ifndef lint
32static const char copyright[] =
33"@(#) Copyright (c) 1990, 1993, 1994\n\
34 The Regents of the University of California. All rights reserved.\n";
35#endif /* not lint */
36
37#ifndef lint
38static char sccsid[] = "@(#)rm.c 8.5 (Berkeley) 4/18/94";
39#endif /* not lint */
40#endif
41#include <sys/cdefs.h>
42__FBSDID("$FreeBSD: head/bin/rm/rm.c 136113 2004-10-04 11:26:01Z des $");
43
44#include <sys/stat.h>
45#include <sys/param.h>
46#include <sys/mount.h>
47
48#include <err.h>
49#include <errno.h>
50#include <fcntl.h>
51#include <fts.h>
52#include <grp.h>
53#include <pwd.h>
54#include <stdio.h>
55#include <stdlib.h>
56#include <string.h>
57#include <sysexits.h>
58#include <unistd.h>
59
60int dflag, eval, fflag, iflag, Pflag, vflag, Wflag, stdin_ok;
61uid_t uid;
62
63int check(char *, char *, struct stat *);
64void checkdot(char **);
65void checkslash(char **);
66void rm_file(char **);
67int rm_overwrite(char *, struct stat *);
68void rm_tree(char **);
69void usage(void);
70
71/*
72 * rm --
73 * This rm is different from historic rm's, but is expected to match
74 * POSIX 1003.2 behavior. The most visible difference is that -f
75 * has two specific effects now, ignore non-existent files and force
76 * file removal.
77 */
78int
79main(int argc, char *argv[])
80{
81 int ch, rflag;
82 char *p;
83
84 /*
85 * Test for the special case where the utility is called as
86 * "unlink", for which the functionality provided is greatly
87 * simplified.
88 */
89 if ((p = rindex(argv[0], '/')) == NULL)
90 p = argv[0];
91 else
92 ++p;
93 if (strcmp(p, "unlink") == 0) {
94 while (getopt(argc, argv, "") != -1)
95 usage();
96 argc -= optind;
97 argv += optind;
98 if (argc != 1)
99 usage();
100 rm_file(&argv[0]);
101 exit(eval);
102 }
103
104 Pflag = rflag = 0;
105 while ((ch = getopt(argc, argv, "dfiPRrvW")) != -1)
106 switch(ch) {
107 case 'd':
108 dflag = 1;
109 break;
110 case 'f':
111 fflag = 1;
112 iflag = 0;
113 break;
114 case 'i':
115 fflag = 0;
116 iflag = 1;
117 break;
118 case 'P':
119 Pflag = 1;
120 break;
121 case 'R':
122 case 'r': /* Compatibility. */
123 rflag = 1;
124 break;
125 case 'v':
126 vflag = 1;
127 break;
128 case 'W':
129 Wflag = 1;
130 break;
131 default:
132 usage();
133 }
134 argc -= optind;
135 argv += optind;
136
137 if (argc < 1) {
138 if (fflag)
139 return (0);
140 usage();
141 }
142
143 checkdot(argv);
144 checkslash(argv);
145 uid = geteuid();
146
147 if (*argv) {
148 stdin_ok = isatty(STDIN_FILENO);
149
150 if (rflag)
151 rm_tree(argv);
152 else
153 rm_file(argv);
154 }
155
156 exit (eval);
157}
158
159void
160rm_tree(char **argv)
161{
162 FTS *fts;
163 FTSENT *p;
164 int needstat;
165 int flags;
166 int rval;
167
168 /*
169 * Remove a file hierarchy. If forcing removal (-f), or interactive
170 * (-i) or can't ask anyway (stdin_ok), don't stat the file.
171 */
172 needstat = !uid || (!fflag && !iflag && stdin_ok);
173
174 /*
175 * If the -i option is specified, the user can skip on the pre-order
176 * visit. The fts_number field flags skipped directories.
177 */
178#define SKIPPED 1
179
180 flags = FTS_PHYSICAL;
181 if (!needstat)
182 flags |= FTS_NOSTAT;
183 if (Wflag)
184 flags |= FTS_WHITEOUT;
185 if (!(fts = fts_open(argv, flags, NULL)))
186 err(1, "fts_open");
187 while ((p = fts_read(fts)) != NULL) {
188 switch (p->fts_info) {
189 case FTS_DNR:
190 if (!fflag || p->fts_errno != ENOENT) {
191 warnx("%s: %s",
192 p->fts_path, strerror(p->fts_errno));
193 eval = 1;
194 }
195 continue;
196 case FTS_ERR:
197 errx(1, "%s: %s", p->fts_path, strerror(p->fts_errno));
198 case FTS_NS:
199 /*
200 * Assume that since fts_read() couldn't stat the
201 * file, it can't be unlinked.
202 */
203 if (!needstat)
204 break;
205 if (!fflag || p->fts_errno != ENOENT) {
206 warnx("%s: %s",
207 p->fts_path, strerror(p->fts_errno));
208 eval = 1;
209 }
210 continue;
211 case FTS_D:
212 /* Pre-order: give user chance to skip. */
213 if (!fflag && !check(p->fts_path, p->fts_accpath,
214 p->fts_statp)) {
215 (void)fts_set(fts, p, FTS_SKIP);
216 p->fts_number = SKIPPED;
217 }
218 else if (!uid &&
219 (p->fts_statp->st_flags & (UF_APPEND|UF_IMMUTABLE)) &&
220 !(p->fts_statp->st_flags & (SF_APPEND|SF_IMMUTABLE)) &&
221 chflags(p->fts_accpath,
222 p->fts_statp->st_flags &= ~(UF_APPEND|UF_IMMUTABLE)) < 0)
223 goto err;
224 continue;
225 case FTS_DP:
226 /* Post-order: see if user skipped. */
227 if (p->fts_number == SKIPPED)
228 continue;
229 break;
230 default:
231 if (!fflag &&
232 !check(p->fts_path, p->fts_accpath, p->fts_statp))
233 continue;
234 }
235
236 rval = 0;
237 if (!uid &&
238 (p->fts_statp->st_flags & (UF_APPEND|UF_IMMUTABLE)) &&
239 !(p->fts_statp->st_flags & (SF_APPEND|SF_IMMUTABLE)))
240 rval = chflags(p->fts_accpath,
241 p->fts_statp->st_flags &= ~(UF_APPEND|UF_IMMUTABLE));
242 if (rval == 0) {
243 /*
244 * If we can't read or search the directory, may still be
245 * able to remove it. Don't print out the un{read,search}able
246 * message unless the remove fails.
247 */
248 switch (p->fts_info) {
249 case FTS_DP:
250 case FTS_DNR:
251 rval = rmdir(p->fts_accpath);
252 if (rval == 0 || (fflag && errno == ENOENT)) {
253 if (rval == 0 && vflag)
254 (void)printf("%s\n",
255 p->fts_path);
256 continue;
257 }
258 break;
259
260 case FTS_W:
261 rval = undelete(p->fts_accpath);
262 if (rval == 0 && (fflag && errno == ENOENT)) {
263 if (vflag)
264 (void)printf("%s\n",
265 p->fts_path);
266 continue;
267 }
268 break;
269
270 case FTS_NS:
271 /*
272 * Assume that since fts_read() couldn't stat
273 * the file, it can't be unlinked.
274 */
275 if (fflag)
276 continue;
277 /* FALLTHROUGH */
278 default:
279 if (Pflag)
280 if (!rm_overwrite(p->fts_accpath, NULL))
281 continue;
282 rval = unlink(p->fts_accpath);
283 if (rval == 0 || (fflag && errno == ENOENT)) {
284 if (rval == 0 && vflag)
285 (void)printf("%s\n",
286 p->fts_path);
287 continue;
288 }
289 }
290 }
291err:
292 warn("%s", p->fts_path);
293 eval = 1;
294 }
295 if (errno)
296 err(1, "fts_read");
297}
298
299void
300rm_file(char **argv)
301{
302 struct stat sb;
303 int rval;
304 char *f;
305
306 /*
307 * Remove a file. POSIX 1003.2 states that, by default, attempting
308 * to remove a directory is an error, so must always stat the file.
309 */
310 while ((f = *argv++) != NULL) {
311 /* Assume if can't stat the file, can't unlink it. */
312 if (lstat(f, &sb)) {
313 if (Wflag) {
314 sb.st_mode = S_IFWHT|S_IWUSR|S_IRUSR;
315 } else {
316 if (!fflag || errno != ENOENT) {
317 warn("%s", f);
318 eval = 1;
319 }
320 continue;
321 }
322 } else if (Wflag) {
323 warnx("%s: %s", f, strerror(EEXIST));
324 eval = 1;
325 continue;
326 }
327
328 if (S_ISDIR(sb.st_mode) && !dflag) {
329 warnx("%s: is a directory", f);
330 eval = 1;
331 continue;
332 }
333 if (!fflag && !S_ISWHT(sb.st_mode) && !check(f, f, &sb))
334 continue;
335 rval = 0;
336 if (!uid &&
337 (sb.st_flags & (UF_APPEND|UF_IMMUTABLE)) &&
338 !(sb.st_flags & (SF_APPEND|SF_IMMUTABLE)))
339 rval = chflags(f, sb.st_flags & ~(UF_APPEND|UF_IMMUTABLE));
340 if (rval == 0) {
341 if (S_ISWHT(sb.st_mode))
342 rval = undelete(f);
343 else if (S_ISDIR(sb.st_mode))
344 rval = rmdir(f);
345 else {
346 if (Pflag)
347 if (!rm_overwrite(f, &sb))
348 continue;
349 rval = unlink(f);
350 }
351 }
352 if (rval && (!fflag || errno != ENOENT)) {
353 warn("%s", f);
354 eval = 1;
355 }
356 if (vflag && rval == 0)
357 (void)printf("%s\n", f);
358 }
359}
360
361/*
362 * rm_overwrite --
363 * Overwrite the file 3 times with varying bit patterns.
364 *
365 * XXX
366 * This is a cheap way to *really* delete files. Note that only regular
367 * files are deleted, directories (and therefore names) will remain.
368 * Also, this assumes a fixed-block file system (like FFS, or a V7 or a
369 * System V file system). In a logging file system, you'll have to have
370 * kernel support.
371 */
372int
373rm_overwrite(char *file, struct stat *sbp)
374{
375 struct stat sb;
376 struct statfs fsb;
377 off_t len;
378 int bsize, fd, wlen;
379 char *buf = NULL;
380
381 fd = -1;
382 if (sbp == NULL) {
383 if (lstat(file, &sb))
384 goto err;
385 sbp = &sb;
386 }
387 if (!S_ISREG(sbp->st_mode))
388 return (1);
389 if ((fd = open(file, O_WRONLY, 0)) == -1)
390 goto err;
391 if (fstatfs(fd, &fsb) == -1)
392 goto err;
393 bsize = MAX(fsb.f_iosize, 1024);
394 if ((buf = malloc(bsize)) == NULL)
395 err(1, "%s: malloc", file);
396
397#define PASS(byte) { \
398 memset(buf, byte, bsize); \
399 for (len = sbp->st_size; len > 0; len -= wlen) { \
400 wlen = len < bsize ? len : bsize; \
401 if (write(fd, buf, wlen) != wlen) \
402 goto err; \
403 } \
404}
405 PASS(0xff);
406 if (fsync(fd) || lseek(fd, (off_t)0, SEEK_SET))
407 goto err;
408 PASS(0x00);
409 if (fsync(fd) || lseek(fd, (off_t)0, SEEK_SET))
410 goto err;
411 PASS(0xff);
412 if (!fsync(fd) && !close(fd)) {
413 free(buf);
414 return (1);
415 }
416
417err: eval = 1;
418 if (buf)
419 free(buf);
420 if (fd != -1)
421 close(fd);
422 warn("%s", file);
423 return (0);
424}
425
426
427int
428check(char *path, char *name, struct stat *sp)
429{
430 int ch, first;
431 char modep[15], *flagsp;
432
433 /* Check -i first. */
434 if (iflag)
435 (void)fprintf(stderr, "remove %s? ", path);
436 else {
437 /*
438 * If it's not a symbolic link and it's unwritable and we're
439 * talking to a terminal, ask. Symbolic links are excluded
440 * because their permissions are meaningless. Check stdin_ok
441 * first because we may not have stat'ed the file.
442 * Also skip this check if the -P option was specified because
443 * we will not be able to overwrite file contents and will
444 * barf later.
445 */
446 if (!stdin_ok || S_ISLNK(sp->st_mode) || Pflag ||
447 (!access(name, W_OK) &&
448 !(sp->st_flags & (SF_APPEND|SF_IMMUTABLE)) &&
449 (!(sp->st_flags & (UF_APPEND|UF_IMMUTABLE)) || !uid)))
450 return (1);
451 strmode(sp->st_mode, modep);
452 if ((flagsp = fflagstostr(sp->st_flags)) == NULL)
453 err(1, "fflagstostr");
454 (void)fprintf(stderr, "override %s%s%s/%s %s%sfor %s? ",
455 modep + 1, modep[9] == ' ' ? "" : " ",
456 user_from_uid(sp->st_uid, 0),
457 group_from_gid(sp->st_gid, 0),
458 *flagsp ? flagsp : "", *flagsp ? " " : "",
459 path);
460 free(flagsp);
461 }
462 (void)fflush(stderr);
463
464 first = ch = getchar();
465 while (ch != '\n' && ch != EOF)
466 ch = getchar();
467 return (first == 'y' || first == 'Y');
468}
469
470#define ISSLASH(a) ((a)[0] == '/' && (a)[1] == '\0')
471void
472checkslash(char **argv)
473{
474 char **t, **u;
475 int complained;
476
477 complained = 0;
478 for (t = argv; *t;) {
479 if (ISSLASH(*t)) {
480 if (!complained++)
481 warnx("\"/\" may not be removed");
482 eval = 1;
483 for (u = t; u[0] != NULL; ++u)
484 u[0] = u[1];
485 } else {
486 ++t;
487 }
488 }
489}
490
491#define ISDOT(a) ((a)[0] == '.' && (!(a)[1] || ((a)[1] == '.' && !(a)[2])))
492void
493checkdot(char **argv)
494{
495 char *p, **save, **t;
496 int complained;
497
498 complained = 0;
499 for (t = argv; *t;) {
500 if ((p = strrchr(*t, '/')) != NULL)
501 ++p;
502 else
503 p = *t;
504 if (ISDOT(p)) {
505 if (!complained++)
506 warnx("\".\" and \"..\" may not be removed");
507 eval = 1;
508 for (save = t; (t[0] = t[1]) != NULL; ++t)
509 continue;
510 t = save;
511 } else
512 ++t;
513 }
514}
515
516void
517usage(void)
518{
519
520 (void)fprintf(stderr, "%s\n%s\n",
521 "usage: rm [-f | -i] [-dPRrvW] file ...",
522 " unlink file");
523 exit(EX_USAGE);
524}