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 <stdint.h> 48 #include <stdlib.h> 49 #include <string.h> 50 #include <sysexits.h> 51 #include <unistd.h> 52 53 static int dflag, eval, fflag, iflag, Pflag, vflag, Wflag, stdin_ok; 54 static int rflag, Iflag, xflag; 55 static uid_t uid; 56 static volatile sig_atomic_t info; 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 #ifdef SIGINFO 65 static void siginfo(int); 66 #endif 67 static void usage(void); 68 69 /* 70 * rm -- 71 * This rm is different from historic rm's, but is expected to match 72 * POSIX 1003.2 behavior. The most visible difference is that -f 73 * has two specific effects now, ignore non-existent files and force 74 * file removal. 75 */ 76 int 77 main(int argc, char *argv[]) 78 { 79 int ch; 80 const char *p; 81 pid_t tty_pgrp; 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 = strrchr(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 = xflag = 0; 104 while ((ch = getopt(argc, argv, "dfiIPRrvWx")) != -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 'I': 118 /* 119 * The -I flag is intended to be generally aliasable 120 * in /etc/csh.cshrc. We apply it only to foreground 121 * processes. 122 */ 123 if (ioctl(0, TIOCGPGRP, &tty_pgrp) == 0) { 124 if (tty_pgrp == getpgrp()) 125 Iflag = 1; 126 } 127 break; 128 case 'P': 129 Pflag = 1; 130 break; 131 case 'R': 132 case 'r': /* Compatibility. */ 133 rflag = 1; 134 break; 135 case 'v': 136 vflag = 1; 137 break; 138 case 'W': 139 #ifdef S_IFWHT 140 Wflag = 1; 141 #endif 142 break; 143 case 'x': 144 xflag = 1; 145 break; 146 default: 147 usage(); 148 } 149 } 150 argc -= optind; 151 argv += optind; 152 153 if (argc < 1) { 154 if (fflag) 155 return 0; 156 usage(); 157 } 158 159 checkdot(argv); 160 uid = geteuid(); 161 162 #ifdef SIGINFO 163 signal(SIGINFO, siginfo); 164 #endif 165 166 if (*argv) { 167 stdin_ok = isatty(STDIN_FILENO); 168 169 if (Iflag && !iflag) { 170 if (check2(argv) == 0) 171 exit (1); 172 } 173 if (rflag) 174 rm_tree(argv); 175 else 176 rm_file(argv); 177 } 178 179 exit (eval); 180 } 181 182 static void 183 rm_tree(char **argv) 184 { 185 FTS *fts; 186 FTSENT *p; 187 int needstat; 188 int flags; 189 int rval; 190 191 /* 192 * Remove a file hierarchy. If forcing removal (-f), or interactive 193 * (-i) or can't ask anyway (stdin_ok), don't stat the file. 194 */ 195 needstat = !uid || (!fflag && !iflag && stdin_ok); 196 197 /* 198 * If the -i option is specified, the user can skip on the pre-order 199 * visit. The fts_number field flags skipped directories. 200 */ 201 #define SKIPPED 1 202 203 flags = FTS_PHYSICAL; 204 if (!needstat) 205 flags |= FTS_NOSTAT; 206 #ifdef S_IFWHT 207 if (Wflag) 208 flags |= FTS_WHITEOUT; 209 #endif 210 if (xflag) 211 flags |= FTS_XDEV; 212 if ((fts = fts_open(argv, flags, NULL)) == NULL) { 213 if (fflag && errno == ENOENT) 214 return; 215 err(1, "fts_open"); 216 } 217 while ((p = fts_read(fts)) != NULL) { 218 switch (p->fts_info) { 219 case FTS_DNR: 220 if (!fflag || p->fts_errno != ENOENT) { 221 warnx("%s: %s", 222 p->fts_path, strerror(p->fts_errno)); 223 eval = 1; 224 } 225 continue; 226 case FTS_ERR: 227 errx(1, "%s: %s", p->fts_path, strerror(p->fts_errno)); 228 case FTS_NS: 229 /* 230 * Assume that since fts_read() couldn't stat 231 * the file, it can't be unlinked. 232 */ 233 if (!needstat) 234 break; 235 if (!fflag || p->fts_errno != ENOENT) { 236 warnx("%s: %s", 237 p->fts_path, strerror(p->fts_errno)); 238 eval = 1; 239 } 240 continue; 241 case FTS_D: 242 /* Pre-order: give user chance to skip. */ 243 if (!fflag && !check(p->fts_path, p->fts_accpath, 244 p->fts_statp)) { 245 fts_set(fts, p, FTS_SKIP); 246 p->fts_number = SKIPPED; 247 } 248 #ifdef _ST_FLAGS_PRESENT_ 249 else if (!uid && 250 (p->fts_statp->st_flags & (UF_APPEND|UF_IMMUTABLE)) && 251 !(p->fts_statp->st_flags & (SF_APPEND|SF_IMMUTABLE)) && 252 lchflags(p->fts_accpath, 253 p->fts_statp->st_flags &= ~(UF_APPEND|UF_IMMUTABLE)) < 0) 254 goto err; 255 #endif 256 continue; 257 case FTS_DP: 258 /* Post-order: see if user skipped. */ 259 if (p->fts_number == SKIPPED) 260 continue; 261 break; 262 default: 263 if (!fflag && 264 !check(p->fts_path, p->fts_accpath, p->fts_statp)) 265 continue; 266 } 267 268 if (info) { 269 info = 0; 270 fprintf(stderr, "Currently removing: %s\n", p->fts_path); 271 } 272 273 rval = 0; 274 #ifdef _ST_FLAGS_PRESENT_ 275 if (!uid && 276 (p->fts_statp->st_flags & (UF_APPEND|UF_IMMUTABLE)) && 277 !(p->fts_statp->st_flags & (SF_APPEND|SF_IMMUTABLE))) 278 rval = lchflags(p->fts_accpath, 279 p->fts_statp->st_flags &= ~(UF_APPEND|UF_IMMUTABLE)); 280 #endif 281 282 if (rval == 0) { 283 /* 284 * If we can't read or search the directory, may still be 285 * able to remove it. Don't print out the un{read,search}able 286 * message unless the remove fails. 287 */ 288 switch (p->fts_info) { 289 case FTS_DP: 290 case FTS_DNR: 291 rval = rmdir(p->fts_accpath); 292 if (rval == 0 || (fflag && errno == ENOENT)) { 293 if (rval == 0 && vflag) 294 printf("%s\n", 295 p->fts_path); 296 continue; 297 } 298 break; 299 #ifdef S_IFWHT 300 case FTS_W: 301 rval = undelete(p->fts_accpath); 302 if (rval == 0 && (fflag && errno == ENOENT)) { 303 if (vflag) 304 printf("%s\n", 305 p->fts_path); 306 continue; 307 } 308 break; 309 #endif 310 case FTS_NS: 311 /* 312 * Assume that since fts_read() couldn't stat 313 * the file, it can't be unlinked. 314 */ 315 if (fflag) 316 continue; 317 /* FALLTHROUGH */ 318 default: 319 if (Pflag) 320 if (!rm_overwrite(p->fts_accpath, NULL)) 321 continue; 322 rval = unlink(p->fts_accpath); 323 if (rval == 0 || (fflag && errno == ENOENT)) { 324 if (rval == 0 && vflag) 325 printf("%s\n", 326 p->fts_path); 327 continue; 328 } 329 } 330 } 331 #ifdef _ST_FLAGS_PRESENT_ 332 err: 333 #endif 334 warn("%s", p->fts_path); 335 eval = 1; 336 } 337 if (errno) 338 err(1, "fts_read"); 339 fts_close(fts); 340 } 341 342 static void 343 rm_file(char **argv) 344 { 345 struct stat sb; 346 int rval; 347 const char *f; 348 349 /* 350 * Remove a file. POSIX 1003.2 states that, by default, attempting 351 * to remove a directory is an error, so must always stat the file. 352 */ 353 while ((f = *argv++) != NULL) { 354 if (info) { 355 info = 0; 356 fprintf(stderr, "Currently removing: %s\n", f); 357 } 358 359 /* Assume if can't stat the file, can't unlink it. */ 360 if (lstat(f, &sb)) { 361 if (Wflag) { 362 #ifdef S_IFWHT 363 sb.st_mode = S_IFWHT|S_IWUSR|S_IRUSR; 364 #endif 365 } else { 366 if (!fflag || errno != ENOENT) { 367 warn("%s", f); 368 eval = 1; 369 } 370 continue; 371 } 372 } else if (Wflag) { 373 warnx("%s: %s", f, strerror(EEXIST)); 374 eval = 1; 375 continue; 376 } 377 378 if (S_ISDIR(sb.st_mode) && !dflag) { 379 warnx("%s: is a directory", f); 380 eval = 1; 381 continue; 382 } 383 if (!fflag && !S_ISWHT(sb.st_mode) && !check(f, f, &sb)) 384 continue; 385 rval = 0; 386 #ifdef _ST_FLAGS_PRESENT_ 387 if (!uid && !S_ISWHT(sb.st_mode) && 388 (sb.st_flags & (UF_APPEND|UF_IMMUTABLE)) && 389 !(sb.st_flags & (SF_APPEND|SF_IMMUTABLE))) 390 rval = lchflags(f, sb.st_flags & ~(UF_APPEND|UF_IMMUTABLE)); 391 #endif 392 if (rval == 0) { 393 #ifdef S_IFWHT 394 if (S_ISWHT(sb.st_mode)) 395 rval = undelete(f); 396 else 397 #endif 398 if (S_ISDIR(sb.st_mode)) 399 rval = rmdir(f); 400 else { 401 if (Pflag) 402 if (!rm_overwrite(f, &sb)) 403 continue; 404 rval = unlink(f); 405 } 406 } 407 if (rval && (!fflag || errno != ENOENT)) { 408 warn("%s", f); 409 eval = 1; 410 } 411 if (vflag && rval == 0) 412 printf("%s\n", f); 413 } 414 } 415 416 /* 417 * rm_overwrite -- 418 * Overwrite the file 3 times with varying bit patterns. 419 * 420 * XXX 421 * This is a cheap way to *really* delete files. Note that only regular 422 * files are deleted, directories (and therefore names) will remain. 423 * Also, this assumes a fixed-block filesystem (like FFS, or a V7 or a 424 * System V filesystem). In a logging filesystem, you'll have to have 425 * kernel support. 426 */ 427 static int 428 rm_overwrite(const char *file, struct stat *sbp) 429 { 430 struct stat sb; 431 struct statfs fsb; 432 off_t len; 433 int bsize, fd, wlen; 434 char *buf = NULL; 435 436 fd = -1; 437 if (sbp == NULL) { 438 if (lstat(file, &sb)) 439 goto err; 440 sbp = &sb; 441 } 442 if (!S_ISREG(sbp->st_mode)) { 443 warnx("%s: cannot overwrite a non-regular file", file); 444 return (1); 445 } 446 if (sbp->st_nlink > 1) { 447 warnx("%s (inode %ju): not overwritten due to multiple links", 448 file, (uintmax_t)sbp->st_ino); 449 return (0); 450 } 451 if ((fd = open(file, O_WRONLY, 0)) == -1) 452 goto err; 453 if (fstatfs(fd, &fsb) == -1) 454 goto err; 455 bsize = MAX(fsb.f_iosize, 1024); 456 if ((buf = malloc(bsize)) == NULL) 457 err(1, "%s malloc failed", file); 458 459 #define PASS(byte) { \ 460 memset(buf, byte, bsize); \ 461 for (len = sbp->st_size; len > 0; len -= wlen) { \ 462 wlen = len < bsize ? len : bsize; \ 463 if (write(fd, buf, wlen) != wlen) \ 464 goto err; \ 465 } \ 466 } 467 PASS(0xff); 468 if (fsync(fd) || lseek(fd, (off_t)0, SEEK_SET)) 469 goto err; 470 PASS(0x00); 471 if (fsync(fd) || lseek(fd, (off_t)0, SEEK_SET)) 472 goto err; 473 PASS(0xff); 474 if (!fsync(fd) && !close(fd)) { 475 free(buf); 476 return (1); 477 } 478 479 err: eval = 1; 480 if (buf) 481 free(buf); 482 if (fd != -1) 483 close(fd); 484 warn("%s", file); 485 return (0); 486 } 487 488 489 static int 490 check(const char *path, const char *name, struct stat *sp) 491 { 492 static int perm_answer = -1; 493 struct choice { 494 int ch; 495 const char *str; 496 int res; 497 int perm; 498 } *choice, choices[] = { 499 { 'y', "yes" , 1, 0 }, 500 { 'n', "no" , 0, 0 }, 501 { 'a', "always", 1, 1 }, 502 { 'v', "never" , 0, 1 }, 503 { 0, NULL, 0, 0 } 504 }; 505 char modep[15], *flagsp = NULL; 506 507 if (perm_answer != -1) 508 return (perm_answer); 509 510 /* Check -i first. */ 511 if (iflag) 512 fprintf(stderr, "remove %s? ", path); 513 else { 514 /* 515 * If it's not a symbolic link and it's unwritable and we're 516 * talking to a terminal, ask. Symbolic links are excluded 517 * because their permissions are meaningless. Check stdin_ok 518 * first because we may not have stat'ed the file. 519 * Also skip this check if the -P option was specified because 520 * we will not be able to overwrite file contents and will 521 * barf later. 522 */ 523 if (!stdin_ok || S_ISLNK(sp->st_mode) || Pflag || 524 (!access(name, W_OK) 525 #ifdef _ST_FLAGS_PRESENT_ 526 && !(sp->st_flags & (SF_APPEND|SF_IMMUTABLE)) && 527 (!(sp->st_flags & (UF_APPEND|UF_IMMUTABLE)) || !uid) 528 #endif 529 )) 530 return (1); 531 strmode(sp->st_mode, modep); 532 #ifdef _ST_FLAGS_PRESENT_ 533 if ((flagsp = fflagstostr(sp->st_flags)) == NULL) 534 err(1, NULL); 535 #endif 536 fprintf(stderr, "override %s%s%s/%s %s%sfor %s? ", 537 modep + 1, modep[9] == ' ' ? "" : " ", 538 user_from_uid(sp->st_uid, 0), 539 group_from_gid(sp->st_gid, 0), 540 *flagsp ? flagsp : "", *flagsp ? " " : "", 541 path); 542 free(flagsp); 543 } 544 fflush(stderr); 545 546 for (;;) { 547 size_t len; 548 char *answer; 549 550 answer = fgetln(stdin, &len); 551 /* clearerr(stdin); */ 552 if (answer == NULL) 553 return (0); 554 if (answer[len - 1] == '\n') 555 len--; 556 if (len == 0) 557 continue; 558 559 for (choice = choices; choice->str != NULL; choice++) { 560 if (len == 1 && choice->ch == answer[0]) 561 goto valid_choice; 562 if (strncasecmp(answer, choice->str, len) == 0) 563 goto valid_choice; 564 } 565 566 fprintf(stderr, "invalid answer, try again (y/n/a/v): "); 567 } 568 569 valid_choice: 570 if (choice->perm) 571 perm_answer = choice->res; 572 return (choice->res); 573 } 574 575 static int 576 check2(char **argv) 577 { 578 struct stat st; 579 int first; 580 int ch; 581 int fcount = 0; 582 int dcount = 0; 583 int i; 584 const char *dname = NULL; 585 586 for (i = 0; argv[i]; ++i) { 587 if (lstat(argv[i], &st) == 0) { 588 if (S_ISDIR(st.st_mode)) { 589 ++dcount; 590 dname = argv[i]; /* only used if 1 dir */ 591 } else { 592 ++fcount; 593 } 594 } 595 } 596 first = 0; 597 while (first != 'n' && first != 'N' && first != 'y' && first != 'Y') { 598 if (dcount && rflag) { 599 fprintf(stderr, "recursively remove"); 600 if (dcount == 1) 601 fprintf(stderr, " %s", dname); 602 else 603 fprintf(stderr, " %d dirs", dcount); 604 if (fcount == 1) 605 fprintf(stderr, " and 1 file"); 606 else if (fcount > 1) 607 fprintf(stderr, " and %d files", fcount); 608 } else if (dcount + fcount > 3) { 609 fprintf(stderr, "remove %d files", dcount + fcount); 610 } else { 611 return(1); 612 } 613 fprintf(stderr, "? "); 614 fflush(stderr); 615 616 first = ch = getchar(); 617 while (ch != '\n' && ch != EOF) 618 ch = getchar(); 619 if (ch == EOF) 620 break; 621 } 622 return (first == 'y' || first == 'Y'); 623 } 624 625 #define ISDOT(a) ((a)[0] == '.' && (!(a)[1] || ((a)[1] == '.' && !(a)[2]))) 626 static void 627 checkdot(char **argv) 628 { 629 char *p, **save, **t; 630 int complained; 631 632 complained = 0; 633 for (t = argv; *t;) { 634 if ((p = strrchr(*t, '/')) != NULL) 635 ++p; 636 else 637 p = *t; 638 if (ISDOT(p)) { 639 if (!complained++) 640 warnx("\".\" and \"..\" may not be removed"); 641 eval = 1; 642 for (save = t; (t[0] = t[1]) != NULL; ++t) 643 continue; 644 t = save; 645 } else 646 ++t; 647 } 648 } 649 650 static void 651 usage(void) 652 { 653 654 fprintf(stderr, "%s\n%s\n", 655 "usage: rm [-f | -i] [-dIPRrvWx] file ...", 656 " unlink file"); 657 exit(EX_USAGE); 658 } 659 660 #ifdef SIGINFO 661 static void 662 siginfo(int notused __unused) 663 { 664 info = 1; 665 } 666 #endif 667