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 */ 37 38 #include <sys/stat.h> 39 #include <sys/param.h> 40 #include <sys/mount.h> 41 #include <sys/ioctl.h> 42 43 #include <err.h> 44 #include <errno.h> 45 #include <fcntl.h> 46 #include <fts.h> 47 #include <grp.h> 48 #include <pwd.h> 49 #include <signal.h> 50 #include <stdio.h> 51 #include <stdlib.h> 52 #include <string.h> 53 #include <sysexits.h> 54 #include <unistd.h> 55 56 static int dflag, eval, fflag, iflag, Pflag, vflag, Wflag, stdin_ok; 57 static int rflag, Iflag, xflag; 58 static uid_t uid; 59 volatile sig_atomic_t info; 60 61 static int check(const char *, const char *, struct stat *); 62 static int check2(char **); 63 static void checkdot(char **); 64 static void rm_file(char **); 65 static int rm_overwrite(const char *, struct stat *); 66 static void rm_tree(char **); 67 static void siginfo(int); 68 static void 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 */ 77 int 78 main(int argc, char *argv[]) 79 { 80 int ch; 81 const char *p; 82 pid_t tty_pgrp; 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 = strrchr(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 = xflag = 0; 105 while ((ch = getopt(argc, argv, "dfiIPRrvWx")) != -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 'I': 119 /* 120 * The -I flag is intended to be generally aliasable 121 * in /etc/csh.cshrc. We apply it only to foreground 122 * processes. 123 */ 124 if (ioctl(0, TIOCGPGRP, &tty_pgrp) == 0) { 125 if (tty_pgrp == getpgrp()) 126 Iflag = 1; 127 } 128 break; 129 case 'P': 130 Pflag = 1; 131 break; 132 case 'R': 133 case 'r': /* Compatibility. */ 134 rflag = 1; 135 break; 136 case 'v': 137 vflag = 1; 138 break; 139 case 'W': 140 Wflag = 1; 141 break; 142 case 'x': 143 xflag = 1; 144 break; 145 default: 146 usage(); 147 } 148 } 149 argc -= optind; 150 argv += optind; 151 152 if (argc < 1) { 153 if (fflag) 154 return 0; 155 usage(); 156 } 157 158 checkdot(argv); 159 uid = geteuid(); 160 161 signal(SIGINFO, siginfo); 162 163 if (*argv) { 164 stdin_ok = isatty(STDIN_FILENO); 165 166 if (Iflag && !iflag) { 167 if (check2(argv) == 0) 168 exit (1); 169 } 170 if (rflag) 171 rm_tree(argv); 172 else 173 rm_file(argv); 174 } 175 176 exit (eval); 177 } 178 179 static void 180 rm_tree(char **argv) 181 { 182 FTS *fts; 183 FTSENT *p; 184 int needstat; 185 int flags; 186 int rval; 187 188 /* 189 * Remove a file hierarchy. If forcing removal (-f), or interactive 190 * (-i) or can't ask anyway (stdin_ok), don't stat the file. 191 */ 192 needstat = !uid || (!fflag && !iflag && stdin_ok); 193 194 /* 195 * If the -i option is specified, the user can skip on the pre-order 196 * visit. The fts_number field flags skipped directories. 197 */ 198 #define SKIPPED 1 199 200 flags = FTS_PHYSICAL; 201 if (!needstat) 202 flags |= FTS_NOSTAT; 203 if (Wflag) 204 flags |= FTS_WHITEOUT; 205 if (xflag) 206 flags |= FTS_XDEV; 207 if ((fts = fts_open(argv, flags, NULL)) == NULL) { 208 if (fflag && errno == ENOENT) 209 return; 210 err(1, NULL); 211 } 212 while ((p = fts_read(fts)) != NULL) { 213 switch (p->fts_info) { 214 case FTS_DNR: 215 if (!fflag || p->fts_errno != ENOENT) { 216 warnx("%s: %s", 217 p->fts_path, strerror(p->fts_errno)); 218 eval = 1; 219 } 220 continue; 221 case FTS_ERR: 222 errx(1, "%s: %s", p->fts_path, strerror(p->fts_errno)); 223 case FTS_NS: 224 /* 225 * Assume that since fts_read() couldn't stat 226 * the file, it can't be unlinked. 227 */ 228 if (!needstat) 229 break; 230 if (!fflag || p->fts_errno != ENOENT) { 231 warnx("%s: %s", 232 p->fts_path, strerror(p->fts_errno)); 233 eval = 1; 234 } 235 continue; 236 case FTS_D: 237 /* Pre-order: give user chance to skip. */ 238 if (!fflag && !check(p->fts_path, p->fts_accpath, 239 p->fts_statp)) { 240 fts_set(fts, p, FTS_SKIP); 241 p->fts_number = SKIPPED; 242 } 243 else if (!uid && 244 (p->fts_statp->st_flags & (UF_APPEND|UF_IMMUTABLE)) && 245 !(p->fts_statp->st_flags & (SF_APPEND|SF_IMMUTABLE)) && 246 lchflags(p->fts_accpath, 247 p->fts_statp->st_flags &= ~(UF_APPEND|UF_IMMUTABLE)) < 0) 248 goto err; 249 continue; 250 case FTS_DP: 251 /* Post-order: see if user skipped. */ 252 if (p->fts_number == SKIPPED) 253 continue; 254 break; 255 default: 256 if (!fflag && 257 !check(p->fts_path, p->fts_accpath, p->fts_statp)) 258 continue; 259 } 260 261 if (info) { 262 info = 0; 263 fprintf(stderr, "Currently removing: %s\n", p->fts_path); 264 } 265 266 rval = 0; 267 if (!uid && 268 (p->fts_statp->st_flags & (UF_APPEND|UF_IMMUTABLE)) && 269 !(p->fts_statp->st_flags & (SF_APPEND|SF_IMMUTABLE))) 270 rval = lchflags(p->fts_accpath, 271 p->fts_statp->st_flags &= ~(UF_APPEND|UF_IMMUTABLE)); 272 273 if (rval == 0) { 274 /* 275 * If we can't read or search the directory, may still be 276 * able to remove it. Don't print out the un{read,search}able 277 * message unless the remove fails. 278 */ 279 switch (p->fts_info) { 280 case FTS_DP: 281 case FTS_DNR: 282 rval = rmdir(p->fts_accpath); 283 if (rval == 0 || (fflag && errno == ENOENT)) { 284 if (rval == 0 && vflag) 285 printf("%s\n", 286 p->fts_path); 287 continue; 288 } 289 break; 290 291 case FTS_W: 292 rval = undelete(p->fts_accpath); 293 if (rval == 0 && (fflag && errno == ENOENT)) { 294 if (vflag) 295 printf("%s\n", 296 p->fts_path); 297 continue; 298 } 299 break; 300 301 case FTS_NS: 302 /* 303 * Assume that since fts_read() couldn't stat 304 * the file, it can't be unlinked. 305 */ 306 if (fflag) 307 continue; 308 /* FALLTHROUGH */ 309 default: 310 if (Pflag) 311 if (!rm_overwrite(p->fts_accpath, NULL)) 312 continue; 313 rval = unlink(p->fts_accpath); 314 if (rval == 0 || (fflag && errno == ENOENT)) { 315 if (rval == 0 && vflag) 316 printf("%s\n", 317 p->fts_path); 318 continue; 319 } 320 } 321 } 322 err: 323 warn("%s", p->fts_path); 324 eval = 1; 325 } 326 if (errno) 327 err(1, "fts_read"); 328 fts_close(fts); 329 } 330 331 static void 332 rm_file(char **argv) 333 { 334 struct stat sb; 335 int rval; 336 const char *f; 337 338 /* 339 * Remove a file. POSIX 1003.2 states that, by default, attempting 340 * to remove a directory is an error, so must always stat the file. 341 */ 342 while ((f = *argv++) != NULL) { 343 if (info) { 344 info = 0; 345 fprintf(stderr, "Currently removing: %s\n", f); 346 } 347 348 /* Assume if can't stat the file, can't unlink it. */ 349 if (lstat(f, &sb)) { 350 if (Wflag) { 351 sb.st_mode = S_IFWHT|S_IWUSR|S_IRUSR; 352 } else { 353 if (!fflag || errno != ENOENT) { 354 warn("%s", f); 355 eval = 1; 356 } 357 continue; 358 } 359 } else if (Wflag) { 360 warnx("%s: %s", f, strerror(EEXIST)); 361 eval = 1; 362 continue; 363 } 364 365 if (S_ISDIR(sb.st_mode) && !dflag) { 366 warnx("%s: is a directory", f); 367 eval = 1; 368 continue; 369 } 370 if (!fflag && !S_ISWHT(sb.st_mode) && !check(f, f, &sb)) 371 continue; 372 rval = 0; 373 if (!uid && 374 (sb.st_flags & (UF_APPEND|UF_IMMUTABLE)) && 375 !(sb.st_flags & (SF_APPEND|SF_IMMUTABLE))) 376 rval = lchflags(f, sb.st_flags & ~(UF_APPEND|UF_IMMUTABLE)); 377 if (rval == 0) { 378 if (S_ISWHT(sb.st_mode)) 379 rval = undelete(f); 380 else if (S_ISDIR(sb.st_mode)) 381 rval = rmdir(f); 382 else { 383 if (Pflag) 384 if (!rm_overwrite(f, &sb)) 385 continue; 386 rval = unlink(f); 387 } 388 } 389 if (rval && (!fflag || errno != ENOENT)) { 390 warn("%s", f); 391 eval = 1; 392 } 393 if (vflag && rval == 0) 394 printf("%s\n", f); 395 } 396 } 397 398 /* 399 * rm_overwrite -- 400 * Overwrite the file 3 times with varying bit patterns. 401 * 402 * XXX 403 * This is a cheap way to *really* delete files. Note that only regular 404 * files are deleted, directories (and therefore names) will remain. 405 * Also, this assumes a fixed-block filesystem (like FFS, or a V7 or a 406 * System V filesystem). In a logging filesystem, you'll have to have 407 * kernel support. 408 */ 409 static int 410 rm_overwrite(const char *file, struct stat *sbp) 411 { 412 struct stat sb; 413 struct statfs fsb; 414 off_t len; 415 int bsize, fd, wlen; 416 char *buf = NULL; 417 418 fd = -1; 419 if (sbp == NULL) { 420 if (lstat(file, &sb)) 421 goto err; 422 sbp = &sb; 423 } 424 if (!S_ISREG(sbp->st_mode)) { 425 warnx("%s: cannot overwrite a non-regular file", file); 426 return (1); 427 } 428 if (sbp->st_nlink > 1) { 429 warnx("%s (inode %ju): not overwritten due to multiple links", 430 file, (uintmax_t)sbp->st_ino); 431 return (0); 432 } 433 if ((fd = open(file, O_WRONLY, 0)) == -1) 434 goto err; 435 if (fstatfs(fd, &fsb) == -1) 436 goto err; 437 bsize = MAX(fsb.f_iosize, 1024); 438 if ((buf = malloc(bsize)) == NULL) 439 err(1, "%s malloc failed", file); 440 441 #define PASS(byte) { \ 442 memset(buf, byte, bsize); \ 443 for (len = sbp->st_size; len > 0; len -= wlen) { \ 444 wlen = len < bsize ? len : bsize; \ 445 if (write(fd, buf, wlen) != wlen) \ 446 goto err; \ 447 } \ 448 } 449 PASS(0xff); 450 if (fsync(fd) || lseek(fd, (off_t)0, SEEK_SET)) 451 goto err; 452 PASS(0x00); 453 if (fsync(fd) || lseek(fd, (off_t)0, SEEK_SET)) 454 goto err; 455 PASS(0xff); 456 if (!fsync(fd) && !close(fd)) { 457 free(buf); 458 return (1); 459 } 460 461 err: eval = 1; 462 if (buf) 463 free(buf); 464 if (fd != -1) 465 close(fd); 466 warn("%s", file); 467 return (0); 468 } 469 470 471 static int 472 check(const char *path, const char *name, struct stat *sp) 473 { 474 static int perm_answer = -1; 475 struct choice { 476 int ch; 477 const char *str; 478 int res; 479 int perm; 480 } *choice, choices[] = { 481 { 'y', "yes" , 1, 0 }, 482 { 'n', "no" , 0, 0 }, 483 { 'a', "always", 1, 1 }, 484 { 'v', "never" , 0, 1 }, 485 { 0, NULL, 0, 0 } 486 }; 487 char modep[15], *flagsp; 488 489 if (perm_answer != -1) 490 return (perm_answer); 491 492 /* Check -i first. */ 493 if (iflag) 494 fprintf(stderr, "remove %s? ", path); 495 else { 496 /* 497 * If it's not a symbolic link and it's unwritable and we're 498 * talking to a terminal, ask. Symbolic links are excluded 499 * because their permissions are meaningless. Check stdin_ok 500 * first because we may not have stat'ed the file. 501 * Also skip this check if the -P option was specified because 502 * we will not be able to overwrite file contents and will 503 * barf later. 504 */ 505 if (!stdin_ok || S_ISLNK(sp->st_mode) || Pflag || 506 (!access(name, W_OK) && 507 !(sp->st_flags & (SF_APPEND|SF_IMMUTABLE)) && 508 (!(sp->st_flags & (UF_APPEND|UF_IMMUTABLE)) || !uid))) 509 return (1); 510 strmode(sp->st_mode, modep); 511 if ((flagsp = fflagstostr(sp->st_flags)) == NULL) 512 err(1, NULL); 513 fprintf(stderr, "override %s%s%s/%s %s%sfor %s? ", 514 modep + 1, modep[9] == ' ' ? "" : " ", 515 user_from_uid(sp->st_uid, 0), 516 group_from_gid(sp->st_gid, 0), 517 *flagsp ? flagsp : "", *flagsp ? " " : "", 518 path); 519 free(flagsp); 520 } 521 fflush(stderr); 522 523 for (;;) { 524 size_t len; 525 char *answer; 526 527 answer = fgetln(stdin, &len); 528 /* clearerr(stdin); */ 529 if (answer == NULL) 530 return (0); 531 if (answer[len - 1] == '\n') 532 len--; 533 if (len == 0) 534 continue; 535 536 for (choice = choices; choice->str != NULL; choice++) { 537 if (len == 1 && choice->ch == answer[0]) 538 goto valid_choice; 539 if (strncasecmp(answer, choice->str, len) == 0) 540 goto valid_choice; 541 } 542 543 fprintf(stderr, "invalid answer, try again (y/n/a/v): "); 544 } 545 546 valid_choice: 547 if (choice->perm) 548 perm_answer = choice->res; 549 return (choice->res); 550 } 551 552 static int 553 check2(char **argv) 554 { 555 struct stat st; 556 int first; 557 int ch; 558 int fcount = 0; 559 int dcount = 0; 560 int i; 561 const char *dname = NULL; 562 563 for (i = 0; argv[i]; ++i) { 564 if (lstat(argv[i], &st) == 0) { 565 if (S_ISDIR(st.st_mode)) { 566 ++dcount; 567 dname = argv[i]; /* only used if 1 dir */ 568 } else { 569 ++fcount; 570 } 571 } 572 } 573 first = 0; 574 while (first != 'n' && first != 'N' && first != 'y' && first != 'Y') { 575 if (dcount && rflag) { 576 fprintf(stderr, "recursively remove"); 577 if (dcount == 1) 578 fprintf(stderr, " %s", dname); 579 else 580 fprintf(stderr, " %d dirs", dcount); 581 if (fcount == 1) 582 fprintf(stderr, " and 1 file"); 583 else if (fcount > 1) 584 fprintf(stderr, " and %d files", fcount); 585 } else if (dcount + fcount > 3) { 586 fprintf(stderr, "remove %d files", dcount + fcount); 587 } else { 588 return(1); 589 } 590 fprintf(stderr, "? "); 591 fflush(stderr); 592 593 first = ch = getchar(); 594 while (ch != '\n' && ch != EOF) 595 ch = getchar(); 596 if (ch == EOF) 597 break; 598 } 599 return (first == 'y' || first == 'Y'); 600 } 601 602 #define ISDOT(a) ((a)[0] == '.' && (!(a)[1] || ((a)[1] == '.' && !(a)[2]))) 603 static void 604 checkdot(char **argv) 605 { 606 char *p, **save, **t; 607 int complained; 608 609 complained = 0; 610 for (t = argv; *t;) { 611 if ((p = strrchr(*t, '/')) != NULL) 612 ++p; 613 else 614 p = *t; 615 if (ISDOT(p)) { 616 if (!complained++) 617 warnx("\".\" and \"..\" may not be removed"); 618 eval = 1; 619 for (save = t; (t[0] = t[1]) != NULL; ++t) 620 continue; 621 t = save; 622 } else 623 ++t; 624 } 625 } 626 627 static void 628 usage(void) 629 { 630 631 fprintf(stderr, "%s\n%s\n", 632 "usage: rm [-f | -i] [-dIPRrvWx] file ...", 633 " unlink file"); 634 exit(EX_USAGE); 635 } 636 637 static void 638 siginfo(int notused __unused) 639 { 640 info = 1; 641 } 642