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 136112 2004-10-04 11:14:12Z 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 rm_file(char **);
66int rm_overwrite(char *, struct stat *);
67void rm_tree(char **);
68void usage(void);
69
70/*
71 * rm --
72 * This rm is different from historic rm's, but is expected to match
73 * POSIX 1003.2 behavior. The most visible difference is that -f
74 * has two specific effects now, ignore non-existent files and force
75 * file removal.
76 */
77int
78main(int argc, char *argv[])
79{
80 int ch, rflag;
81 char *p;
82
83 /*
84 * Test for the special case where the utility is called as
85 * "unlink", for which the functionality provided is greatly
86 * simplified.
87 */
88 if ((p = rindex(argv[0], '/')) == NULL)
89 p = argv[0];
90 else
91 ++p;
92 if (strcmp(p, "unlink") == 0) {
93 while (getopt(argc, argv, "") != -1)
94 usage();
95 argc -= optind;
96 argv += optind;
97 if (argc != 1)
98 usage();
99 rm_file(&argv[0]);
100 exit(eval);
101 }
102
103 Pflag = rflag = 0;
104 while ((ch = getopt(argc, argv, "dfiPRrvW")) != -1)
105 switch(ch) {
106 case 'd':
107 dflag = 1;
108 break;
109 case 'f':
110 fflag = 1;
111 iflag = 0;
112 break;
113 case 'i':
114 fflag = 0;
115 iflag = 1;
116 break;
117 case 'P':
118 Pflag = 1;
119 break;
120 case 'R':
121 case 'r': /* Compatibility. */
122 rflag = 1;
123 break;
124 case 'v':
125 vflag = 1;
126 break;
127 case 'W':
128 Wflag = 1;
129 break;
130 default:
131 usage();
132 }
133 argc -= optind;
134 argv += optind;
135
136 if (argc < 1) {
137 if (fflag)
138 return (0);
139 usage();
140 }
141
142 checkdot(argv);
143 uid = geteuid();
144
145 if (*argv) {
146 stdin_ok = isatty(STDIN_FILENO);
147
148 if (rflag)
149 rm_tree(argv);
150 else
151 rm_file(argv);
152 }
153
154 exit (eval);
155}
156
157void
158rm_tree(char **argv)
159{
160 FTS *fts;
161 FTSENT *p;
162 int needstat;
163 int flags;
164 int rval;
165
166 /*
167 * Remove a file hierarchy. If forcing removal (-f), or interactive
168 * (-i) or can't ask anyway (stdin_ok), don't stat the file.
169 */
170 needstat = !uid || (!fflag && !iflag && stdin_ok);
171
172 /*
173 * If the -i option is specified, the user can skip on the pre-order
174 * visit. The fts_number field flags skipped directories.
175 */
176#define SKIPPED 1
177
178 flags = FTS_PHYSICAL;
179 if (!needstat)
180 flags |= FTS_NOSTAT;
181 if (Wflag)
182 flags |= FTS_WHITEOUT;
183 if (!(fts = fts_open(argv, flags, NULL)))
184 err(1, "fts_open");
185 while ((p = fts_read(fts)) != NULL) {
186 switch (p->fts_info) {
187 case FTS_DNR:
188 if (!fflag || p->fts_errno != ENOENT) {
189 warnx("%s: %s",
190 p->fts_path, strerror(p->fts_errno));
191 eval = 1;
192 }
193 continue;
194 case FTS_ERR:
195 errx(1, "%s: %s", p->fts_path, strerror(p->fts_errno));
196 case FTS_NS:
197 /*
198 * Assume that since fts_read() couldn't stat the
199 * file, it can't be unlinked.
200 */
201 if (!needstat)
202 break;
203 if (!fflag || p->fts_errno != ENOENT) {
204 warnx("%s: %s",
205 p->fts_path, strerror(p->fts_errno));
206 eval = 1;
207 }
208 continue;
209 case FTS_D:
210 /* Pre-order: give user chance to skip. */
211 if (!fflag && !check(p->fts_path, p->fts_accpath,
212 p->fts_statp)) {
213 (void)fts_set(fts, p, FTS_SKIP);
214 p->fts_number = SKIPPED;
215 }
216 else if (!uid &&
217 (p->fts_statp->st_flags & (UF_APPEND|UF_IMMUTABLE)) &&
218 !(p->fts_statp->st_flags & (SF_APPEND|SF_IMMUTABLE)) &&
219 chflags(p->fts_accpath,
220 p->fts_statp->st_flags &= ~(UF_APPEND|UF_IMMUTABLE)) < 0)
221 goto err;
222 continue;
223 case FTS_DP:
224 /* Post-order: see if user skipped. */
225 if (p->fts_number == SKIPPED)
226 continue;
227 break;
228 default:
229 if (!fflag &&
230 !check(p->fts_path, p->fts_accpath, p->fts_statp))
231 continue;
232 }
233
234 rval = 0;
235 if (!uid &&
236 (p->fts_statp->st_flags & (UF_APPEND|UF_IMMUTABLE)) &&
237 !(p->fts_statp->st_flags & (SF_APPEND|SF_IMMUTABLE)))
238 rval = chflags(p->fts_accpath,
239 p->fts_statp->st_flags &= ~(UF_APPEND|UF_IMMUTABLE));
240 if (rval == 0) {
241 /*
242 * If we can't read or search the directory, may still be
243 * able to remove it. Don't print out the un{read,search}able
244 * message unless the remove fails.
245 */
246 switch (p->fts_info) {
247 case FTS_DP:
248 case FTS_DNR:
249 rval = rmdir(p->fts_accpath);
250 if (rval == 0 || (fflag && errno == ENOENT)) {
251 if (rval == 0 && vflag)
252 (void)printf("%s\n",
253 p->fts_path);
254 continue;
255 }
256 break;
257
258 case FTS_W:
259 rval = undelete(p->fts_accpath);
260 if (rval == 0 && (fflag && errno == ENOENT)) {
261 if (vflag)
262 (void)printf("%s\n",
263 p->fts_path);
264 continue;
265 }
266 break;
267
268 case FTS_NS:
269 /*
270 * Assume that since fts_read() couldn't stat
271 * the file, it can't be unlinked.
272 */
273 if (fflag)
274 continue;
275 /* FALLTHROUGH */
276 default:
277 if (Pflag)
278 if (!rm_overwrite(p->fts_accpath, NULL))
279 continue;
280 rval = unlink(p->fts_accpath);
281 if (rval == 0 || (fflag && errno == ENOENT)) {
282 if (rval == 0 && vflag)
283 (void)printf("%s\n",
284 p->fts_path);
285 continue;
286 }
287 }
288 }
289err:
290 warn("%s", p->fts_path);
291 eval = 1;
292 }
293 if (errno)
294 err(1, "fts_read");
295}
296
297void
298rm_file(char **argv)
299{
300 struct stat sb;
301 int rval;
302 char *f;
303
304 /*
305 * Remove a file. POSIX 1003.2 states that, by default, attempting
306 * to remove a directory is an error, so must always stat the file.
307 */
308 while ((f = *argv++) != NULL) {
309 /* Assume if can't stat the file, can't unlink it. */
310 if (lstat(f, &sb)) {
311 if (Wflag) {
312 sb.st_mode = S_IFWHT|S_IWUSR|S_IRUSR;
313 } else {
314 if (!fflag || errno != ENOENT) {
315 warn("%s", f);
316 eval = 1;
317 }
318 continue;
319 }
320 } else if (Wflag) {
321 warnx("%s: %s", f, strerror(EEXIST));
322 eval = 1;
323 continue;
324 }
325
326 if (S_ISDIR(sb.st_mode) && !dflag) {
327 warnx("%s: is a directory", f);
328 eval = 1;
329 continue;
330 }
331 if (!fflag && !S_ISWHT(sb.st_mode) && !check(f, f, &sb))
332 continue;
333 rval = 0;
334 if (!uid &&
335 (sb.st_flags & (UF_APPEND|UF_IMMUTABLE)) &&
336 !(sb.st_flags & (SF_APPEND|SF_IMMUTABLE)))
337 rval = chflags(f, sb.st_flags & ~(UF_APPEND|UF_IMMUTABLE));
338 if (rval == 0) {
339 if (S_ISWHT(sb.st_mode))
340 rval = undelete(f);
341 else if (S_ISDIR(sb.st_mode))
342 rval = rmdir(f);
343 else {
344 if (Pflag)
345 if (!rm_overwrite(f, &sb))
346 continue;
347 rval = unlink(f);
348 }
349 }
350 if (rval && (!fflag || errno != ENOENT)) {
351 warn("%s", f);
352 eval = 1;
353 }
354 if (vflag && rval == 0)
355 (void)printf("%s\n", f);
356 }
357}
358
359/*
360 * rm_overwrite --
361 * Overwrite the file 3 times with varying bit patterns.
362 *
363 * XXX
364 * This is a cheap way to *really* delete files. Note that only regular
365 * files are deleted, directories (and therefore names) will remain.
366 * Also, this assumes a fixed-block file system (like FFS, or a V7 or a
367 * System V file system). In a logging file system, you'll have to have
368 * kernel support.
369 */
370int
371rm_overwrite(char *file, struct stat *sbp)
372{
373 struct stat sb;
374 struct statfs fsb;
375 off_t len;
376 int bsize, fd, wlen;
377 char *buf = NULL;
378
379 fd = -1;
380 if (sbp == NULL) {
381 if (lstat(file, &sb))
382 goto err;
383 sbp = &sb;
384 }
385 if (!S_ISREG(sbp->st_mode))
386 return (1);
387 if ((fd = open(file, O_WRONLY, 0)) == -1)
388 goto err;
389 if (fstatfs(fd, &fsb) == -1)
390 goto err;
391 bsize = MAX(fsb.f_iosize, 1024);
392 if ((buf = malloc(bsize)) == NULL)
393 err(1, "%s: malloc", file);
394
395#define PASS(byte) { \
396 memset(buf, byte, bsize); \
397 for (len = sbp->st_size; len > 0; len -= wlen) { \
398 wlen = len < bsize ? len : bsize; \
399 if (write(fd, buf, wlen) != wlen) \
400 goto err; \
401 } \
402}
403 PASS(0xff);
404 if (fsync(fd) || lseek(fd, (off_t)0, SEEK_SET))
405 goto err;
406 PASS(0x00);
407 if (fsync(fd) || lseek(fd, (off_t)0, SEEK_SET))
408 goto err;
409 PASS(0xff);
410 if (!fsync(fd) && !close(fd)) {
411 free(buf);
412 return (1);
413 }
414
415err: eval = 1;
416 if (buf)
417 free(buf);
418 if (fd != -1)
419 close(fd);
420 warn("%s", file);
421 return (0);
422}
423
424
425int
426check(char *path, char *name, struct stat *sp)
427{
428 int ch, first;
429 char modep[15], *flagsp;
430
431 /* Check -i first. */
432 if (iflag)
433 (void)fprintf(stderr, "remove %s? ", path);
434 else {
435 /*
436 * If it's not a symbolic link and it's unwritable and we're
437 * talking to a terminal, ask. Symbolic links are excluded
438 * because their permissions are meaningless. Check stdin_ok
439 * first because we may not have stat'ed the file.
440 * Also skip this check if the -P option was specified because
441 * we will not be able to overwrite file contents and will
442 * barf later.
443 */
444 if (!stdin_ok || S_ISLNK(sp->st_mode) || Pflag ||
445 (!access(name, W_OK) &&
446 !(sp->st_flags & (SF_APPEND|SF_IMMUTABLE)) &&
447 (!(sp->st_flags & (UF_APPEND|UF_IMMUTABLE)) || !uid)))
448 return (1);
449 strmode(sp->st_mode, modep);
450 if ((flagsp = fflagstostr(sp->st_flags)) == NULL)
451 err(1, "fflagstostr");
452 (void)fprintf(stderr, "override %s%s%s/%s %s%sfor %s? ",
453 modep + 1, modep[9] == ' ' ? "" : " ",
454 user_from_uid(sp->st_uid, 0),
455 group_from_gid(sp->st_gid, 0),
456 *flagsp ? flagsp : "", *flagsp ? " " : "",
457 path);
458 free(flagsp);
459 }
460 (void)fflush(stderr);
461
462 first = ch = getchar();
463 while (ch != '\n' && ch != EOF)
464 ch = getchar();
465 return (first == 'y' || first == 'Y');
466}
467
468#define ISDOT(a) ((a)[0] == '.' && (!(a)[1] || ((a)[1] == '.' && !(a)[2])))
469void
470checkdot(char **argv)
471{
472 char *p, **save, **t;
473 int complained;
474
475 complained = 0;
476 for (t = argv; *t;) {
477 if ((p = strrchr(*t, '/')) != NULL)
478 ++p;
479 else
480 p = *t;
481 if (ISDOT(p)) {
482 if (!complained++)
483 warnx("\".\" and \"..\" may not be removed");
484 eval = 1;
485 for (save = t; (t[0] = t[1]) != NULL; ++t)
486 continue;
487 t = save;
488 } else
489 ++t;
490 }
491}
492
493void
494usage(void)
495{
496
497 (void)fprintf(stderr, "%s\n%s\n",
498 "usage: rm [-f | -i] [-dPRrvW] file ...",
499 " unlink file");
500 exit(EX_USAGE);
501}