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. 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 * @(#) Copyright (c) 1990, 1993, 1994 The Regents of the University of California. All rights reserved. 30 * @(#)rm.c 8.5 (Berkeley) 4/18/94 31 * $FreeBSD: src/bin/rm/rm.c,v 1.29.2.5 2002/07/12 07:25:48 tjr Exp $ 32 */ 33 34 #include <sys/stat.h> 35 #include <sys/param.h> 36 #include <sys/mount.h> 37 #include <sys/ioctl.h> 38 39 #include <err.h> 40 #include <errno.h> 41 #include <fcntl.h> 42 #include <fts.h> 43 #include <grp.h> 44 #include <pwd.h> 45 #include <signal.h> 46 #include <stdio.h> 47 #include <stdlib.h> 48 #include <string.h> 49 #include <sysexits.h> 50 #include <unistd.h> 51 52 static int dflag, eval, fflag, iflag, Pflag, vflag, Wflag, stdin_ok; 53 static int rflag, Iflag, xflag; 54 static uid_t uid; 55 static volatile sig_atomic_t info; 56 57 static int check(const char *, const char *, struct stat *); 58 static int check2(char **); 59 static void checkdot(char **); 60 static void rm_file(char **); 61 static int rm_overwrite(const char *, struct stat *); 62 static void rm_tree(char **); 63 static void siginfo(int); 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 = xflag = 0; 101 while ((ch = getopt(argc, argv, "dfiIPRrvWx")) != -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 case 'x': 139 xflag = 1; 140 break; 141 default: 142 usage(); 143 } 144 } 145 argc -= optind; 146 argv += optind; 147 148 if (argc < 1) { 149 if (fflag) 150 return 0; 151 usage(); 152 } 153 154 checkdot(argv); 155 uid = geteuid(); 156 157 signal(SIGINFO, siginfo); 158 159 if (*argv) { 160 stdin_ok = isatty(STDIN_FILENO); 161 162 if (Iflag && !iflag) { 163 if (check2(argv) == 0) 164 exit (1); 165 } 166 if (rflag) 167 rm_tree(argv); 168 else 169 rm_file(argv); 170 } 171 172 exit (eval); 173 } 174 175 static void 176 rm_tree(char **argv) 177 { 178 FTS *fts; 179 FTSENT *p; 180 int needstat; 181 int flags; 182 int rval; 183 184 /* 185 * Remove a file hierarchy. If forcing removal (-f), or interactive 186 * (-i) or can't ask anyway (stdin_ok), don't stat the file. 187 */ 188 needstat = !uid || (!fflag && !iflag && stdin_ok); 189 190 /* 191 * If the -i option is specified, the user can skip on the pre-order 192 * visit. The fts_number field flags skipped directories. 193 */ 194 #define SKIPPED 1 195 196 flags = FTS_PHYSICAL; 197 if (!needstat) 198 flags |= FTS_NOSTAT; 199 if (Wflag) 200 flags |= FTS_WHITEOUT; 201 if (xflag) 202 flags |= FTS_XDEV; 203 if ((fts = fts_open(argv, flags, NULL)) == NULL) { 204 if (fflag && errno == ENOENT) 205 return; 206 err(1, "fts_open"); 207 } 208 while ((p = fts_read(fts)) != NULL) { 209 switch (p->fts_info) { 210 case FTS_DNR: 211 if (!fflag || p->fts_errno != ENOENT) { 212 warnx("%s: %s", 213 p->fts_path, strerror(p->fts_errno)); 214 eval = 1; 215 } 216 continue; 217 case FTS_ERR: 218 errx(1, "%s: %s", p->fts_path, strerror(p->fts_errno)); 219 case FTS_NS: 220 /* 221 * Assume that since fts_read() couldn't stat 222 * the file, it can't be unlinked. 223 */ 224 if (!needstat) 225 break; 226 if (!fflag || p->fts_errno != ENOENT) { 227 warnx("%s: %s", 228 p->fts_path, strerror(p->fts_errno)); 229 eval = 1; 230 } 231 continue; 232 case FTS_D: 233 /* Pre-order: give user chance to skip. */ 234 if (!fflag && !check(p->fts_path, p->fts_accpath, 235 p->fts_statp)) { 236 fts_set(fts, p, FTS_SKIP); 237 p->fts_number = SKIPPED; 238 } 239 else if (!uid && 240 (p->fts_statp->st_flags & (UF_APPEND|UF_IMMUTABLE)) && 241 !(p->fts_statp->st_flags & (SF_APPEND|SF_IMMUTABLE)) && 242 lchflags(p->fts_accpath, 243 p->fts_statp->st_flags &= ~(UF_APPEND|UF_IMMUTABLE)) < 0) 244 goto err; 245 continue; 246 case FTS_DP: 247 /* Post-order: see if user skipped. */ 248 if (p->fts_number == SKIPPED) 249 continue; 250 break; 251 default: 252 if (!fflag && 253 !check(p->fts_path, p->fts_accpath, p->fts_statp)) 254 continue; 255 } 256 257 if (info) { 258 info = 0; 259 fprintf(stderr, "Currently removing: %s\n", p->fts_path); 260 } 261 262 rval = 0; 263 if (!uid && 264 (p->fts_statp->st_flags & (UF_APPEND|UF_IMMUTABLE)) && 265 !(p->fts_statp->st_flags & (SF_APPEND|SF_IMMUTABLE))) 266 rval = lchflags(p->fts_accpath, 267 p->fts_statp->st_flags &= ~(UF_APPEND|UF_IMMUTABLE)); 268 269 if (rval == 0) { 270 /* 271 * If we can't read or search the directory, may still be 272 * able to remove it. Don't print out the un{read,search}able 273 * message unless the remove fails. 274 */ 275 switch (p->fts_info) { 276 case FTS_DP: 277 case FTS_DNR: 278 rval = rmdir(p->fts_accpath); 279 if (rval == 0 || (fflag && errno == ENOENT)) { 280 if (rval == 0 && vflag) 281 printf("%s\n", 282 p->fts_path); 283 continue; 284 } 285 break; 286 287 case FTS_W: 288 rval = undelete(p->fts_accpath); 289 if (rval == 0 && (fflag && errno == ENOENT)) { 290 if (vflag) 291 printf("%s\n", 292 p->fts_path); 293 continue; 294 } 295 break; 296 297 case FTS_NS: 298 /* 299 * Assume that since fts_read() couldn't stat 300 * the file, it can't be unlinked. 301 */ 302 if (fflag) 303 continue; 304 /* FALLTHROUGH */ 305 default: 306 if (Pflag) 307 if (!rm_overwrite(p->fts_accpath, NULL)) 308 continue; 309 rval = unlink(p->fts_accpath); 310 if (rval == 0 || (fflag && errno == ENOENT)) { 311 if (rval == 0 && vflag) 312 printf("%s\n", 313 p->fts_path); 314 continue; 315 } 316 } 317 } 318 err: 319 warn("%s", p->fts_path); 320 eval = 1; 321 } 322 if (errno) 323 err(1, "fts_read"); 324 fts_close(fts); 325 } 326 327 static void 328 rm_file(char **argv) 329 { 330 struct stat sb; 331 int rval; 332 const char *f; 333 334 /* 335 * Remove a file. POSIX 1003.2 states that, by default, attempting 336 * to remove a directory is an error, so must always stat the file. 337 */ 338 while ((f = *argv++) != NULL) { 339 if (info) { 340 info = 0; 341 fprintf(stderr, "Currently removing: %s\n", f); 342 } 343 344 /* Assume if can't stat the file, can't unlink it. */ 345 if (lstat(f, &sb)) { 346 if (Wflag) { 347 sb.st_mode = S_IFWHT|S_IWUSR|S_IRUSR; 348 } else { 349 if (!fflag || errno != ENOENT) { 350 warn("%s", f); 351 eval = 1; 352 } 353 continue; 354 } 355 } else if (Wflag) { 356 warnx("%s: %s", f, strerror(EEXIST)); 357 eval = 1; 358 continue; 359 } 360 361 if (S_ISDIR(sb.st_mode) && !dflag) { 362 warnx("%s: is a directory", f); 363 eval = 1; 364 continue; 365 } 366 if (!fflag && !S_ISWHT(sb.st_mode) && !check(f, f, &sb)) 367 continue; 368 rval = 0; 369 if (!uid && !S_ISWHT(sb.st_mode) && 370 (sb.st_flags & (UF_APPEND|UF_IMMUTABLE)) && 371 !(sb.st_flags & (SF_APPEND|SF_IMMUTABLE))) 372 rval = lchflags(f, sb.st_flags & ~(UF_APPEND|UF_IMMUTABLE)); 373 if (rval == 0) { 374 if (S_ISWHT(sb.st_mode)) 375 rval = undelete(f); 376 else if (S_ISDIR(sb.st_mode)) 377 rval = rmdir(f); 378 else { 379 if (Pflag) 380 if (!rm_overwrite(f, &sb)) 381 continue; 382 rval = unlink(f); 383 } 384 } 385 if (rval && (!fflag || errno != ENOENT)) { 386 warn("%s", f); 387 eval = 1; 388 } 389 if (vflag && rval == 0) 390 printf("%s\n", f); 391 } 392 } 393 394 /* 395 * rm_overwrite -- 396 * Overwrite the file 3 times with varying bit patterns. 397 * 398 * XXX 399 * This is a cheap way to *really* delete files. Note that only regular 400 * files are deleted, directories (and therefore names) will remain. 401 * Also, this assumes a fixed-block filesystem (like FFS, or a V7 or a 402 * System V filesystem). In a logging filesystem, you'll have to have 403 * kernel support. 404 */ 405 static int 406 rm_overwrite(const char *file, struct stat *sbp) 407 { 408 struct stat sb; 409 struct statfs fsb; 410 off_t len; 411 int bsize, fd, wlen; 412 char *buf = NULL; 413 414 fd = -1; 415 if (sbp == NULL) { 416 if (lstat(file, &sb)) 417 goto err; 418 sbp = &sb; 419 } 420 if (!S_ISREG(sbp->st_mode)) { 421 warnx("%s: cannot overwrite a non-regular file", file); 422 return (1); 423 } 424 if (sbp->st_nlink > 1) { 425 warnx("%s (inode %ju): not overwritten due to multiple links", 426 file, (uintmax_t)sbp->st_ino); 427 return (0); 428 } 429 if ((fd = open(file, O_WRONLY, 0)) == -1) 430 goto err; 431 if (fstatfs(fd, &fsb) == -1) 432 goto err; 433 bsize = MAX(fsb.f_iosize, 1024); 434 if ((buf = malloc(bsize)) == NULL) 435 err(1, "%s malloc failed", file); 436 437 #define PASS(byte) { \ 438 memset(buf, byte, bsize); \ 439 for (len = sbp->st_size; len > 0; len -= wlen) { \ 440 wlen = len < bsize ? len : bsize; \ 441 if (write(fd, buf, wlen) != wlen) \ 442 goto err; \ 443 } \ 444 } 445 PASS(0xff); 446 if (fsync(fd) || lseek(fd, (off_t)0, SEEK_SET)) 447 goto err; 448 PASS(0x00); 449 if (fsync(fd) || lseek(fd, (off_t)0, SEEK_SET)) 450 goto err; 451 PASS(0xff); 452 if (!fsync(fd) && !close(fd)) { 453 free(buf); 454 return (1); 455 } 456 457 err: eval = 1; 458 if (buf) 459 free(buf); 460 if (fd != -1) 461 close(fd); 462 warn("%s", file); 463 return (0); 464 } 465 466 467 static int 468 check(const char *path, const char *name, struct stat *sp) 469 { 470 static int perm_answer = -1; 471 struct choice { 472 int ch; 473 const char *str; 474 int res; 475 int perm; 476 } *choice, choices[] = { 477 { 'y', "yes" , 1, 0 }, 478 { 'n', "no" , 0, 0 }, 479 { 'a', "always", 1, 1 }, 480 { 'v', "never" , 0, 1 }, 481 { 0, NULL, 0, 0 } 482 }; 483 char modep[15], *flagsp; 484 485 if (perm_answer != -1) 486 return (perm_answer); 487 488 /* Check -i first. */ 489 if (iflag) 490 fprintf(stderr, "remove %s? ", path); 491 else { 492 /* 493 * If it's not a symbolic link and it's unwritable and we're 494 * talking to a terminal, ask. Symbolic links are excluded 495 * because their permissions are meaningless. Check stdin_ok 496 * first because we may not have stat'ed the file. 497 * Also skip this check if the -P option was specified because 498 * we will not be able to overwrite file contents and will 499 * barf later. 500 */ 501 if (!stdin_ok || S_ISLNK(sp->st_mode) || Pflag || 502 (!access(name, W_OK) && 503 !(sp->st_flags & (SF_APPEND|SF_IMMUTABLE)) && 504 (!(sp->st_flags & (UF_APPEND|UF_IMMUTABLE)) || !uid))) 505 return (1); 506 strmode(sp->st_mode, modep); 507 if ((flagsp = fflagstostr(sp->st_flags)) == NULL) 508 err(1, NULL); 509 fprintf(stderr, "override %s%s%s/%s %s%sfor %s? ", 510 modep + 1, modep[9] == ' ' ? "" : " ", 511 user_from_uid(sp->st_uid, 0), 512 group_from_gid(sp->st_gid, 0), 513 *flagsp ? flagsp : "", *flagsp ? " " : "", 514 path); 515 free(flagsp); 516 } 517 fflush(stderr); 518 519 for (;;) { 520 size_t len; 521 char *answer; 522 523 answer = fgetln(stdin, &len); 524 /* clearerr(stdin); */ 525 if (answer == NULL) 526 return (0); 527 if (answer[len - 1] == '\n') 528 len--; 529 if (len == 0) 530 continue; 531 532 for (choice = choices; choice->str != NULL; choice++) { 533 if (len == 1 && choice->ch == answer[0]) 534 goto valid_choice; 535 if (strncasecmp(answer, choice->str, len) == 0) 536 goto valid_choice; 537 } 538 539 fprintf(stderr, "invalid answer, try again (y/n/a/v): "); 540 } 541 542 valid_choice: 543 if (choice->perm) 544 perm_answer = choice->res; 545 return (choice->res); 546 } 547 548 static int 549 check2(char **argv) 550 { 551 struct stat st; 552 int first; 553 int ch; 554 int fcount = 0; 555 int dcount = 0; 556 int i; 557 const char *dname = NULL; 558 559 for (i = 0; argv[i]; ++i) { 560 if (lstat(argv[i], &st) == 0) { 561 if (S_ISDIR(st.st_mode)) { 562 ++dcount; 563 dname = argv[i]; /* only used if 1 dir */ 564 } else { 565 ++fcount; 566 } 567 } 568 } 569 first = 0; 570 while (first != 'n' && first != 'N' && first != 'y' && first != 'Y') { 571 if (dcount && rflag) { 572 fprintf(stderr, "recursively remove"); 573 if (dcount == 1) 574 fprintf(stderr, " %s", dname); 575 else 576 fprintf(stderr, " %d dirs", dcount); 577 if (fcount == 1) 578 fprintf(stderr, " and 1 file"); 579 else if (fcount > 1) 580 fprintf(stderr, " and %d files", fcount); 581 } else if (dcount + fcount > 3) { 582 fprintf(stderr, "remove %d files", dcount + fcount); 583 } else { 584 return(1); 585 } 586 fprintf(stderr, "? "); 587 fflush(stderr); 588 589 first = ch = getchar(); 590 while (ch != '\n' && ch != EOF) 591 ch = getchar(); 592 if (ch == EOF) 593 break; 594 } 595 return (first == 'y' || first == 'Y'); 596 } 597 598 #define ISDOT(a) ((a)[0] == '.' && (!(a)[1] || ((a)[1] == '.' && !(a)[2]))) 599 static void 600 checkdot(char **argv) 601 { 602 char *p, **save, **t; 603 int complained; 604 605 complained = 0; 606 for (t = argv; *t;) { 607 if ((p = strrchr(*t, '/')) != NULL) 608 ++p; 609 else 610 p = *t; 611 if (ISDOT(p)) { 612 if (!complained++) 613 warnx("\".\" and \"..\" may not be removed"); 614 eval = 1; 615 for (save = t; (t[0] = t[1]) != NULL; ++t) 616 continue; 617 t = save; 618 } else 619 ++t; 620 } 621 } 622 623 static void 624 usage(void) 625 { 626 627 fprintf(stderr, "%s\n%s\n", 628 "usage: rm [-f | -i] [-dIPRrvWx] file ...", 629 " unlink file"); 630 exit(EX_USAGE); 631 } 632 633 static void 634 siginfo(int notused __unused) 635 { 636 info = 1; 637 } 638