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 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#) Copyright (c) 1990, 1993, 1994 The Regents of the University of California. All rights reserved. 34 * @(#)rm.c 8.5 (Berkeley) 4/18/94 35 * $FreeBSD: src/bin/rm/rm.c,v 1.29.2.5 2002/07/12 07:25:48 tjr Exp $ 36 * $DragonFly: src/bin/rm/rm.c,v 1.16 2006/06/19 12:08:25 corecode Exp $ 37 */ 38 39 #include <sys/stat.h> 40 #include <sys/param.h> 41 #include <sys/mount.h> 42 #include <sys/ioctl.h> 43 44 #include <err.h> 45 #include <errno.h> 46 #include <fcntl.h> 47 #include <fts.h> 48 #include <stdio.h> 49 #include <stdlib.h> 50 #include <string.h> 51 #include <sysexits.h> 52 #include <unistd.h> 53 54 int dflag, eval, fflag, iflag, Pflag, vflag, Wflag, stdin_ok; 55 int rflag, Iflag; 56 uid_t uid; 57 58 static int check(const char *, const char *, struct stat *); 59 static int check2(char **); 60 static void checkdot(char **); 61 static void rm_file(char **); 62 static int rm_overwrite(const char *, struct stat *); 63 static void rm_tree(char **); 64 static void usage(void); 65 66 /* 67 * rm -- 68 * This rm is different from historic rm's, but is expected to match 69 * POSIX 1003.2 behavior. The most visible difference is that -f 70 * has two specific effects now, ignore non-existent files and force 71 * file removal. 72 */ 73 int 74 main(int argc, char *argv[]) 75 { 76 int ch; 77 const char *p; 78 pid_t tty_pgrp; 79 80 /* 81 * Test for the special case where the utility is called as 82 * "unlink", for which the functionality provided is greatly 83 * simplified. 84 */ 85 if ((p = strrchr(argv[0], '/')) == NULL) 86 p = argv[0]; 87 else 88 ++p; 89 if (strcmp(p, "unlink") == 0) { 90 while (getopt(argc, argv, "") != -1) 91 usage(); 92 argc -= optind; 93 argv += optind; 94 if (argc != 1) 95 usage(); 96 rm_file(&argv[0]); 97 exit(eval); 98 } 99 100 Pflag = rflag = 0; 101 while ((ch = getopt(argc, argv, "dfiIPRrvW")) != -1) { 102 switch(ch) { 103 case 'd': 104 dflag = 1; 105 break; 106 case 'f': 107 fflag = 1; 108 iflag = 0; 109 break; 110 case 'i': 111 fflag = 0; 112 iflag = 1; 113 break; 114 case 'I': 115 /* 116 * The -I flag is intended to be generally aliasable 117 * in /etc/csh.cshrc. We apply it only to foreground 118 * processes. 119 */ 120 if (ioctl(0, TIOCGPGRP, &tty_pgrp) == 0) { 121 if (tty_pgrp == getpgrp()) 122 Iflag = 1; 123 } 124 break; 125 case 'P': 126 Pflag = 1; 127 break; 128 case 'R': 129 case 'r': /* Compatibility. */ 130 rflag = 1; 131 break; 132 case 'v': 133 vflag = 1; 134 break; 135 case 'W': 136 Wflag = 1; 137 break; 138 default: 139 usage(); 140 } 141 } 142 argc -= optind; 143 argv += optind; 144 145 if (argc < 1) { 146 if (fflag) 147 return 0; 148 usage(); 149 } 150 151 checkdot(argv); 152 uid = geteuid(); 153 154 if (*argv) { 155 stdin_ok = isatty(STDIN_FILENO); 156 157 if (Iflag && !iflag) { 158 if (check2(argv) == 0) 159 exit (1); 160 } 161 if (rflag) 162 rm_tree(argv); 163 else 164 rm_file(argv); 165 } 166 167 exit (eval); 168 } 169 170 static void 171 rm_tree(char **argv) 172 { 173 FTS *fts; 174 FTSENT *p; 175 int needstat; 176 int flags; 177 int rval; 178 179 /* 180 * Remove a file hierarchy. If forcing removal (-f), or interactive 181 * (-i) or can't ask anyway (stdin_ok), don't stat the file. 182 */ 183 needstat = !uid || (!fflag && !iflag && stdin_ok); 184 185 /* 186 * If the -i option is specified, the user can skip on the pre-order 187 * visit. The fts_number field flags skipped directories. 188 */ 189 #define SKIPPED 1 190 191 flags = FTS_PHYSICAL; 192 if (!needstat) 193 flags |= FTS_NOSTAT; 194 if (Wflag) 195 flags |= FTS_WHITEOUT; 196 if ((fts = fts_open(argv, flags, NULL)) == NULL) { 197 if (fflag && errno == ENOENT) 198 return; 199 err(1, NULL); 200 } 201 while ((p = fts_read(fts)) != NULL) { 202 switch (p->fts_info) { 203 case FTS_DNR: 204 if (!fflag || p->fts_errno != ENOENT) { 205 warnx("%s: %s", 206 p->fts_path, strerror(p->fts_errno)); 207 eval = 1; 208 } 209 continue; 210 case FTS_ERR: 211 errx(1, "%s: %s", p->fts_path, strerror(p->fts_errno)); 212 case FTS_NS: 213 /* 214 * Assume that since fts_read() couldn't stat 215 * the file, it can't be unlinked. 216 */ 217 if (!needstat) 218 break; 219 if (!fflag || p->fts_errno != ENOENT) { 220 warnx("%s: %s", 221 p->fts_path, strerror(p->fts_errno)); 222 eval = 1; 223 } 224 continue; 225 case FTS_D: 226 /* Pre-order: give user chance to skip. */ 227 if (!fflag && !check(p->fts_path, p->fts_accpath, 228 p->fts_statp)) { 229 fts_set(fts, p, FTS_SKIP); 230 p->fts_number = SKIPPED; 231 } 232 else if (!uid && 233 (p->fts_statp->st_flags & (UF_APPEND|UF_IMMUTABLE)) && 234 !(p->fts_statp->st_flags & (SF_APPEND|SF_IMMUTABLE)) && 235 chflags(p->fts_accpath, 236 p->fts_statp->st_flags &= ~(UF_APPEND|UF_IMMUTABLE)) < 0) 237 goto err; 238 continue; 239 case FTS_DP: 240 /* Post-order: see if user skipped. */ 241 if (p->fts_number == SKIPPED) 242 continue; 243 break; 244 default: 245 if (!fflag && 246 !check(p->fts_path, p->fts_accpath, p->fts_statp)) 247 continue; 248 } 249 250 rval = 0; 251 if (!uid && 252 (p->fts_statp->st_flags & (UF_APPEND|UF_IMMUTABLE)) && 253 !(p->fts_statp->st_flags & (SF_APPEND|SF_IMMUTABLE))) 254 rval = chflags(p->fts_accpath, 255 p->fts_statp->st_flags &= ~(UF_APPEND|UF_IMMUTABLE)); 256 if (rval == 0) { 257 /* 258 * If we can't read or search the directory, may still be 259 * able to remove it. Don't print out the un{read,search}able 260 * message unless the remove fails. 261 */ 262 switch (p->fts_info) { 263 case FTS_DP: 264 case FTS_DNR: 265 rval = rmdir(p->fts_accpath); 266 if (rval == 0 || (fflag && errno == ENOENT)) { 267 if (rval == 0 && vflag) 268 printf("%s\n", 269 p->fts_path); 270 continue; 271 } 272 break; 273 274 case FTS_W: 275 rval = undelete(p->fts_accpath); 276 if (rval == 0 && (fflag && errno == ENOENT)) { 277 if (vflag) 278 printf("%s\n", 279 p->fts_path); 280 continue; 281 } 282 break; 283 284 case FTS_NS: 285 /* 286 * Assume that since fts_read() couldn't stat 287 * the file, it can't be unlinked. 288 */ 289 if (fflag) 290 continue; 291 /* FALLTHROUGH */ 292 default: 293 if (Pflag) 294 if (!rm_overwrite(p->fts_accpath, NULL)) 295 continue; 296 rval = unlink(p->fts_accpath); 297 if (rval == 0 || (fflag && errno == ENOENT)) { 298 if (rval == 0 && vflag) 299 printf("%s\n", 300 p->fts_path); 301 continue; 302 } 303 } 304 } 305 err: 306 warn("%s", p->fts_path); 307 eval = 1; 308 } 309 if (errno) 310 err(1, "fts_read"); 311 fts_close(fts); 312 } 313 314 static void 315 rm_file(char **argv) 316 { 317 struct stat sb; 318 int rval; 319 const char *f; 320 321 /* 322 * Remove a file. POSIX 1003.2 states that, by default, attempting 323 * to remove a directory is an error, so must always stat the file. 324 */ 325 while ((f = *argv++) != NULL) { 326 /* Assume if can't stat the file, can't unlink it. */ 327 if (lstat(f, &sb)) { 328 if (Wflag) { 329 sb.st_mode = S_IFWHT|S_IWUSR|S_IRUSR; 330 } else { 331 if (!fflag || errno != ENOENT) { 332 warn("%s", f); 333 eval = 1; 334 } 335 continue; 336 } 337 } else if (Wflag) { 338 warnx("%s: %s", f, strerror(EEXIST)); 339 eval = 1; 340 continue; 341 } 342 343 if (S_ISDIR(sb.st_mode) && !dflag) { 344 warnx("%s: is a directory", f); 345 eval = 1; 346 continue; 347 } 348 if (!fflag && !S_ISWHT(sb.st_mode) && !check(f, f, &sb)) 349 continue; 350 rval = 0; 351 if (!uid && 352 (sb.st_flags & (UF_APPEND|UF_IMMUTABLE)) && 353 !(sb.st_flags & (SF_APPEND|SF_IMMUTABLE))) 354 rval = chflags(f, sb.st_flags & ~(UF_APPEND|UF_IMMUTABLE)); 355 if (rval == 0) { 356 if (S_ISWHT(sb.st_mode)) 357 rval = undelete(f); 358 else if (S_ISDIR(sb.st_mode)) 359 rval = rmdir(f); 360 else { 361 if (Pflag) 362 if (!rm_overwrite(f, &sb)) 363 continue; 364 rval = unlink(f); 365 } 366 } 367 if (rval && (!fflag || errno != ENOENT)) { 368 warn("%s", f); 369 eval = 1; 370 } 371 if (vflag && rval == 0) 372 printf("%s\n", f); 373 } 374 } 375 376 /* 377 * rm_overwrite -- 378 * Overwrite the file 3 times with varying bit patterns. 379 * 380 * XXX 381 * This is a cheap way to *really* delete files. Note that only regular 382 * files are deleted, directories (and therefore names) will remain. 383 * Also, this assumes a fixed-block filesystem (like FFS, or a V7 or a 384 * System V filesystem). In a logging filesystem, you'll have to have 385 * kernel support. 386 */ 387 static int 388 rm_overwrite(const char *file, struct stat *sbp) 389 { 390 struct stat sb; 391 struct statfs fsb; 392 off_t len; 393 int bsize, fd, wlen; 394 char *buf = NULL; 395 396 fd = -1; 397 if (sbp == NULL) { 398 if (lstat(file, &sb)) 399 goto err; 400 sbp = &sb; 401 } 402 if (!S_ISREG(sbp->st_mode)) { 403 warnx("%s: cannot overwrite a non-regular file", file); 404 return (1); 405 } 406 if ((fd = open(file, O_WRONLY, 0)) == -1) 407 goto err; 408 if (fstatfs(fd, &fsb) == -1) 409 goto err; 410 bsize = MAX(fsb.f_iosize, 1024); 411 if ((buf = malloc(bsize)) == NULL) 412 err(1, "%s malloc failed", file); 413 414 #define PASS(byte) { \ 415 memset(buf, byte, bsize); \ 416 for (len = sbp->st_size; len > 0; len -= wlen) { \ 417 wlen = len < bsize ? len : bsize; \ 418 if (write(fd, buf, wlen) != wlen) \ 419 goto err; \ 420 } \ 421 } 422 PASS(0xff); 423 if (fsync(fd) || lseek(fd, (off_t)0, SEEK_SET)) 424 goto err; 425 PASS(0x00); 426 if (fsync(fd) || lseek(fd, (off_t)0, SEEK_SET)) 427 goto err; 428 PASS(0xff); 429 if (!fsync(fd) && !close(fd)) { 430 free(buf); 431 return (1); 432 } 433 434 err: eval = 1; 435 if (buf) 436 free(buf); 437 if (fd != -1) 438 close(fd); 439 warn("%s", file); 440 return (0); 441 } 442 443 444 static int 445 check(const char *path, const char *name, struct stat *sp) 446 { 447 static int perm_answer = -1; 448 struct choice { 449 int ch; 450 const char *str; 451 int res; 452 int perm; 453 } *choice, choices[] = { 454 { 'y', "yes" , 1, 0 }, 455 { 'n', "no" , 0, 0 }, 456 { 'a', "always", 1, 1 }, 457 { 'v', "never" , 0, 1 }, 458 { 0, NULL, 0, 0 } 459 }; 460 char modep[15], *flagsp; 461 462 if (perm_answer != -1) 463 return (perm_answer); 464 465 /* Check -i first. */ 466 if (iflag) 467 fprintf(stderr, "remove %s? ", path); 468 else { 469 /* 470 * If it's not a symbolic link and it's unwritable and we're 471 * talking to a terminal, ask. Symbolic links are excluded 472 * because their permissions are meaningless. Check stdin_ok 473 * first because we may not have stat'ed the file. 474 * Also skip this check if the -P option was specified because 475 * we will not be able to overwrite file contents and will 476 * barf later. 477 */ 478 if (!stdin_ok || S_ISLNK(sp->st_mode) || Pflag || 479 (!access(name, W_OK) && 480 !(sp->st_flags & (SF_APPEND|SF_IMMUTABLE)) && 481 (!(sp->st_flags & (UF_APPEND|UF_IMMUTABLE)) || !uid))) 482 return (1); 483 strmode(sp->st_mode, modep); 484 if ((flagsp = fflagstostr(sp->st_flags)) == NULL) 485 err(1, NULL); 486 fprintf(stderr, "override %s%s%s/%s %s%sfor %s? ", 487 modep + 1, modep[9] == ' ' ? "" : " ", 488 user_from_uid(sp->st_uid, 0), 489 group_from_gid(sp->st_gid, 0), 490 *flagsp ? flagsp : "", *flagsp ? " " : "", 491 path); 492 free(flagsp); 493 } 494 fflush(stderr); 495 496 for (;;) { 497 size_t len; 498 char *answer; 499 500 answer = fgetln(stdin, &len); 501 /* clearerr(stdin); */ 502 if (answer == NULL) 503 return (0); 504 if (answer[len - 1] == '\n') 505 len--; 506 if (len == 0) 507 continue; 508 509 for (choice = choices; choice->str != NULL; choice++) { 510 if (len == 1 && choice->ch == answer[0]) 511 goto valid_choice; 512 if (strncasecmp(answer, choice->str, len) == 0) 513 goto valid_choice; 514 } 515 516 fprintf(stderr, "invalid answer, try again (y/n/a/v): "); 517 } 518 519 valid_choice: 520 if (choice->perm) 521 perm_answer = choice->res; 522 return (choice->res); 523 } 524 525 static int 526 check2(char **argv) 527 { 528 struct stat st; 529 int first; 530 int ch; 531 int fcount = 0; 532 int dcount = 0; 533 int i; 534 const char *dname = NULL; 535 536 for (i = 0; argv[i]; ++i) { 537 if (lstat(argv[i], &st) == 0) { 538 if (S_ISDIR(st.st_mode)) { 539 ++dcount; 540 dname = argv[i]; /* only used if 1 dir */ 541 } else { 542 ++fcount; 543 } 544 } 545 } 546 first = 0; 547 while (first != 'n' && first != 'N' && first != 'y' && first != 'Y') { 548 if (dcount && rflag) { 549 fprintf(stderr, "recursively remove"); 550 if (dcount == 1) 551 fprintf(stderr, " %s", dname); 552 else 553 fprintf(stderr, " %d dirs", dcount); 554 if (fcount == 1) 555 fprintf(stderr, " and 1 file"); 556 else if (fcount > 1) 557 fprintf(stderr, " and %d files", fcount); 558 } else if (dcount + fcount > 3) { 559 fprintf(stderr, "remove %d files", dcount + fcount); 560 } else { 561 return(1); 562 } 563 fprintf(stderr, "? "); 564 fflush(stderr); 565 566 first = ch = getchar(); 567 while (ch != '\n' && ch != EOF) 568 ch = getchar(); 569 if (ch == EOF) 570 break; 571 } 572 return (first == 'y' || first == 'Y'); 573 } 574 575 #define ISDOT(a) ((a)[0] == '.' && (!(a)[1] || ((a)[1] == '.' && !(a)[2]))) 576 static void 577 checkdot(char **argv) 578 { 579 char *p, **save, **t; 580 int complained; 581 582 complained = 0; 583 for (t = argv; *t;) { 584 if ((p = strrchr(*t, '/')) != NULL) 585 ++p; 586 else 587 p = *t; 588 if (ISDOT(p)) { 589 if (!complained++) 590 warnx("\".\" and \"..\" may not be removed"); 591 eval = 1; 592 for (save = t; (t[0] = t[1]) != NULL; ++t) 593 continue; 594 t = save; 595 } else 596 ++t; 597 } 598 } 599 600 static void 601 usage(void) 602 { 603 604 fprintf(stderr, "%s\n%s\n", 605 "usage: rm [-f | -i] [-dIPRrvW] file ...", 606 " unlink file"); 607 exit(EX_USAGE); 608 } 609