bin/rm/rm.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-3-Clause
   3  *
   4  * Copyright (c) 1990, 1993, 1994
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. Neither the name of the University nor the names of its contributors
  16  *    may be used to endorse or promote products derived from this software
  17  *    without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  */
  31
  32 #if 0
  33 #ifndef lint
  34 static const char copyright[] =
  35 "@(#) Copyright (c) 1990, 1993, 1994\n\
  36         The Regents of the University of California.  All rights reserved.\n";
  37 #endif /* not lint */
  38
  39 #ifndef lint
  40 static char sccsid[] = "@(#)rm.c        8.5 (Berkeley) 4/18/94";
  41 #endif /* not lint */
  42 #endif
  43 #include <sys/cdefs.h>
  44 __FBSDID("$FreeBSD$");
  45
  46 #include <sys/stat.h>
  47 #include <sys/param.h>
  48 #include <sys/mount.h>
  49
  50 #include <err.h>
  51 #include <errno.h>
  52 #include <fcntl.h>
  53 #include <fts.h>
  54 #include <grp.h>
  55 #include <locale.h>
  56 #include <pwd.h>
  57 #include <stdint.h>
  58 #include <stdio.h>
  59 #include <stdlib.h>
  60 #include <string.h>
  61 #include <sysexits.h>
  62 #include <unistd.h>
  63
  64 static int dflag, eval, fflag, iflag, vflag, Wflag, stdin_ok;
  65 static int rflag, Iflag, xflag;
  66 static uid_t uid;
  67 static volatile sig_atomic_t info;
  68
  69 static int      check(const char *, const char *, struct stat *);
  70 static int      check2(char **);
  71 static void     checkdot(char **);
  72 static void     checkslash(char **);
  73 static void     rm_file(char **);
  74 static void     rm_tree(char **);
  75 static void siginfo(int __unused);
  76 static void     usage(void);
  77
  78 /*
  79  * rm --
  80  *      This rm is different from historic rm's, but is expected to match
  81  *      POSIX 1003.2 behavior.  The most visible difference is that -f
  82  *      has two specific effects now, ignore non-existent files and force
  83  *      file removal.
  84  */
  85 int
  86 main(int argc, char *argv[])
  87 {
  88         int ch;
  89         char *p;
  90
  91         (void)setlocale(LC_ALL, "");
  92
  93         /*
  94          * Test for the special case where the utility is called as
  95          * "unlink", for which the functionality provided is greatly
  96          * simplified.
  97          */
  98         if ((p = strrchr(argv[0], '/')) == NULL)
  99                 p = argv[0];
 100         else
 101                 ++p;
 102         if (strcmp(p, "unlink") == 0) {
 103                 if (argc == 2)
 104                         rm_file(&argv[1]);
 105                 else if (argc == 3 && strcmp(argv[1], "--") == 0)
 106                         rm_file(&argv[2]);
 107                 else
 108                         usage();
 109                 exit(eval);
 110         }
 111
 112         rflag = xflag = 0;
 113         while ((ch = getopt(argc, argv, "dfiIPRrvWx")) != -1)
 114                 switch(ch) {
 115                 case 'd':
 116                         dflag = 1;
 117                         break;
 118                 case 'f':
 119                         fflag = 1;
 120                         iflag = 0;
 121                         break;
 122                 case 'i':
 123                         fflag = 0;
 124                         iflag = 1;
 125                         break;
 126                 case 'I':
 127                         Iflag = 1;
 128                         break;
 129                 case 'P':
 130                         /* Compatibility no-op. */
 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         argc -= optind;
 149         argv += optind;
 150
 151         if (argc < 1) {
 152                 if (fflag)
 153                         return (0);
 154                 usage();
 155         }
 156
 157         checkdot(argv);
 158         checkslash(argv);
 159         uid = geteuid();
 160
 161         (void)signal(SIGINFO, siginfo);
 162         if (*argv) {
 163                 stdin_ok = isatty(STDIN_FILENO);
 164
 165                 if (Iflag) {
 166                         if (check2(argv) == 0)
 167                                 exit (1);
 168                 }
 169                 if (rflag)
 170                         rm_tree(argv);
 171                 else
 172                         rm_file(argv);
 173         }
 174
 175         exit (eval);
 176 }
 177
 178 static void
 179 rm_tree(char **argv)
 180 {
 181         FTS *fts;
 182         FTSENT *p;
 183         int needstat;
 184         int flags;
 185         int rval;
 186
 187         /*
 188          * Remove a file hierarchy.  If forcing removal (-f), or interactive
 189          * (-i) or can't ask anyway (stdin_ok), don't stat the file.
 190          */
 191         needstat = !uid || (!fflag && !iflag && stdin_ok);
 192
 193         /*
 194          * If the -i option is specified, the user can skip on the pre-order
 195          * visit.  The fts_number field flags skipped directories.
 196          */
 197 #define SKIPPED 1
 198
 199         flags = FTS_PHYSICAL;
 200         if (!needstat)
 201                 flags |= FTS_NOSTAT;
 202         if (Wflag)
 203                 flags |= FTS_WHITEOUT;
 204         if (xflag)
 205                 flags |= FTS_XDEV;
 206         if (!(fts = fts_open(argv, flags, NULL))) {
 207                 if (fflag && errno == ENOENT)
 208                         return;
 209                 err(1, "fts_open");
 210         }
 211         while ((p = fts_read(fts)) != NULL) {
 212                 switch (p->fts_info) {
 213                 case FTS_DNR:
 214                         if (!fflag || p->fts_errno != ENOENT) {
 215                                 warnx("%s: %s",
 216                                     p->fts_path, strerror(p->fts_errno));
 217                                 eval = 1;
 218                         }
 219                         continue;
 220                 case FTS_ERR:
 221                         errx(1, "%s: %s", p->fts_path, strerror(p->fts_errno));
 222                 case FTS_NS:
 223                         /*
 224                          * Assume that since fts_read() couldn't stat the
 225                          * file, it can't be unlinked.
 226                          */
 227                         if (!needstat)
 228                                 break;
 229                         if (!fflag || p->fts_errno != ENOENT) {
 230                                 warnx("%s: %s",
 231                                     p->fts_path, strerror(p->fts_errno));
 232                                 eval = 1;
 233                         }
 234                         continue;
 235                 case FTS_D:
 236                         /* Pre-order: give user chance to skip. */
 237                         if (!fflag && !check(p->fts_path, p->fts_accpath,
 238                             p->fts_statp)) {
 239                                 (void)fts_set(fts, p, FTS_SKIP);
 240                                 p->fts_number = SKIPPED;
 241                         }
 242                         else if (!uid &&
 243                                  (p->fts_statp->st_flags & (UF_APPEND|UF_IMMUTABLE)) &&
 244                                  !(p->fts_statp->st_flags & (SF_APPEND|SF_IMMUTABLE)) &&
 245                                  lchflags(p->fts_accpath,
 246                                          p->fts_statp->st_flags &= ~(UF_APPEND|UF_IMMUTABLE)) < 0)
 247                                 goto err;
 248                         continue;
 249                 case FTS_DP:
 250                         /* Post-order: see if user skipped. */
 251                         if (p->fts_number == SKIPPED)
 252                                 continue;
 253                         break;
 254                 default:
 255                         if (!fflag &&
 256                             !check(p->fts_path, p->fts_accpath, p->fts_statp))
 257                                 continue;
 258                 }
 259
 260                 rval = 0;
 261                 if (!uid &&
 262                     (p->fts_statp->st_flags & (UF_APPEND|UF_IMMUTABLE)) &&
 263                     !(p->fts_statp->st_flags & (SF_APPEND|SF_IMMUTABLE)))
 264                         rval = lchflags(p->fts_accpath,
 265                                        p->fts_statp->st_flags &= ~(UF_APPEND|UF_IMMUTABLE));
 266                 if (rval == 0) {
 267                         /*
 268                          * If we can't read or search the directory, may still be
 269                          * able to remove it.  Don't print out the un{read,search}able
 270                          * message unless the remove fails.
 271                          */
 272                         switch (p->fts_info) {
 273                         case FTS_DP:
 274                         case FTS_DNR:
 275                                 rval = rmdir(p->fts_accpath);
 276                                 if (rval == 0 || (fflag && errno == ENOENT)) {
 277                                         if (rval == 0 && vflag)
 278                                                 (void)printf("%s\n",
 279                                                     p->fts_path);
 280                                         if (rval == 0 && info) {
 281                                                 info = 0;
 282                                                 (void)printf("%s\n",
 283                                                     p->fts_path);
 284                                         }
 285                                         continue;
 286                                 }
 287                                 break;
 288
 289                         case FTS_W:
 290                                 rval = undelete(p->fts_accpath);
 291                                 if (rval == 0 && (fflag && errno == ENOENT)) {
 292                                         if (vflag)
 293                                                 (void)printf("%s\n",
 294                                                     p->fts_path);
 295                                         if (info) {
 296                                                 info = 0;
 297                                                 (void)printf("%s\n",
 298                                                     p->fts_path);
 299                                         }
 300                                         continue;
 301                                 }
 302                                 break;
 303
 304                         case FTS_NS:
 305                                 /*
 306                                  * Assume that since fts_read() couldn't stat
 307                                  * the file, it can't be unlinked.
 308                                  */
 309                                 if (fflag)
 310                                         continue;
 311                                 /* FALLTHROUGH */
 312
 313                         case FTS_F:
 314                         case FTS_NSOK:
 315                         default:
 316                                 rval = unlink(p->fts_accpath);
 317                                 if (rval == 0 || (fflag && errno == ENOENT)) {
 318                                         if (rval == 0 && vflag)
 319                                                 (void)printf("%s\n",
 320                                                     p->fts_path);
 321                                         if (rval == 0 && info) {
 322                                                 info = 0;
 323                                                 (void)printf("%s\n",
 324                                                     p->fts_path);
 325                                         }
 326                                         continue;
 327                                 }
 328                         }
 329                 }
 330 err:
 331                 warn("%s", p->fts_path);
 332                 eval = 1;
 333         }
 334         if (!fflag && errno)
 335                 err(1, "fts_read");
 336         fts_close(fts);
 337 }
 338
 339 static void
 340 rm_file(char **argv)
 341 {
 342         struct stat sb;
 343         int rval;
 344         char *f;
 345
 346         /*
 347          * Remove a file.  POSIX 1003.2 states that, by default, attempting
 348          * to remove a directory is an error, so must always stat the file.
 349          */
 350         while ((f = *argv++) != NULL) {
 351                 /* Assume if can't stat the file, can't unlink it. */
 352                 if (lstat(f, &sb)) {
 353                         if (Wflag) {
 354                                 sb.st_mode = S_IFWHT|S_IWUSR|S_IRUSR;
 355                         } else {
 356                                 if (!fflag || errno != ENOENT) {
 357                                         warn("%s", f);
 358                                         eval = 1;
 359                                 }
 360                                 continue;
 361                         }
 362                 } else if (Wflag) {
 363                         warnx("%s: %s", f, strerror(EEXIST));
 364                         eval = 1;
 365                         continue;
 366                 }
 367
 368                 if (S_ISDIR(sb.st_mode) && !dflag) {
 369                         warnx("%s: is a directory", f);
 370                         eval = 1;
 371                         continue;
 372                 }
 373                 if (!fflag && !S_ISWHT(sb.st_mode) && !check(f, f, &sb))
 374                         continue;
 375                 rval = 0;
 376                 if (!uid && !S_ISWHT(sb.st_mode) &&
 377                     (sb.st_flags & (UF_APPEND|UF_IMMUTABLE)) &&
 378                     !(sb.st_flags & (SF_APPEND|SF_IMMUTABLE)))
 379                         rval = lchflags(f, sb.st_flags & ~(UF_APPEND|UF_IMMUTABLE));
 380                 if (rval == 0) {
 381                         if (S_ISWHT(sb.st_mode))
 382                                 rval = undelete(f);
 383                         else if (S_ISDIR(sb.st_mode))
 384                                 rval = rmdir(f);
 385                         else
 386                                 rval = unlink(f);
 387                 }
 388                 if (rval && (!fflag || errno != ENOENT)) {
 389                         warn("%s", f);
 390                         eval = 1;
 391                 }
 392                 if (vflag && rval == 0)
 393                         (void)printf("%s\n", f);
 394                 if (info && rval == 0) {
 395                         info = 0;
 396                         (void)printf("%s\n", f);
 397                 }
 398         }
 399 }
 400
 401 static int
 402 check(const char *path, const char *name, struct stat *sp)
 403 {
 404         int ch, first;
 405         char modep[15], *flagsp;
 406
 407         /* Check -i first. */
 408         if (iflag)
 409                 (void)fprintf(stderr, "remove %s? ", path);
 410         else {
 411                 /*
 412                  * If it's not a symbolic link and it's unwritable and we're
 413                  * talking to a terminal, ask.  Symbolic links are excluded
 414                  * because their permissions are meaningless.  Check stdin_ok
 415                  * first because we may not have stat'ed the file.
 416                  */
 417                 if (!stdin_ok || S_ISLNK(sp->st_mode) ||
 418                     (!access(name, W_OK) &&
 419                     !(sp->st_flags & (SF_APPEND|SF_IMMUTABLE)) &&
 420                     (!(sp->st_flags & (UF_APPEND|UF_IMMUTABLE)) || !uid)))
 421                         return (1);
 422                 strmode(sp->st_mode, modep);
 423                 if ((flagsp = fflagstostr(sp->st_flags)) == NULL)
 424                         err(1, "fflagstostr");
 425                 (void)fprintf(stderr, "override %s%s%s/%s %s%sfor %s? ",
 426                     modep + 1, modep[10] == ' ' ? "" : " ",
 427                     user_from_uid(sp->st_uid, 0),
 428                     group_from_gid(sp->st_gid, 0),
 429                     *flagsp ? flagsp : "", *flagsp ? " " : "",
 430                     path);
 431                 free(flagsp);
 432         }
 433         (void)fflush(stderr);
 434
 435         first = ch = getchar();
 436         while (ch != '\n' && ch != EOF)
 437                 ch = getchar();
 438         return (first == 'y' || first == 'Y');
 439 }
 440
 441 #define ISSLASH(a)      ((a)[0] == '/' && (a)[1] == '\0')
 442 static void
 443 checkslash(char **argv)
 444 {
 445         char **t, **u;
 446         int complained;
 447
 448         complained = 0;
 449         for (t = argv; *t;) {
 450                 if (ISSLASH(*t)) {
 451                         if (!complained++)
 452                                 warnx("\"/\" may not be removed");
 453                         eval = 1;
 454                         for (u = t; u[0] != NULL; ++u)
 455                                 u[0] = u[1];
 456                 } else {
 457                         ++t;
 458                 }
 459         }
 460 }
 461
 462 static int
 463 check2(char **argv)
 464 {
 465         struct stat st;
 466         int first;
 467         int ch;
 468         int fcount = 0;
 469         int dcount = 0;
 470         int i;
 471         const char *dname = NULL;
 472
 473         for (i = 0; argv[i]; ++i) {
 474                 if (lstat(argv[i], &st) == 0) {
 475                         if (S_ISDIR(st.st_mode)) {
 476                                 ++dcount;
 477                                 dname = argv[i];    /* only used if 1 dir */
 478                         } else {
 479                                 ++fcount;
 480                         }
 481                 }
 482         }
 483         first = 0;
 484         while (first != 'n' && first != 'N' && first != 'y' && first != 'Y') {
 485                 if (dcount && rflag) {
 486                         fprintf(stderr, "recursively remove");
 487                         if (dcount == 1)
 488                                 fprintf(stderr, " %s", dname);
 489                         else
 490                                 fprintf(stderr, " %d dirs", dcount);
 491                         if (fcount == 1)
 492                                 fprintf(stderr, " and 1 file");
 493                         else if (fcount > 1)
 494                                 fprintf(stderr, " and %d files", fcount);
 495                 } else if (dcount + fcount > 3) {
 496                         fprintf(stderr, "remove %d files", dcount + fcount);
 497                 } else {
 498                         return(1);
 499                 }
 500                 fprintf(stderr, "? ");
 501                 fflush(stderr);
 502
 503                 first = ch = getchar();
 504                 while (ch != '\n' && ch != EOF)
 505                         ch = getchar();
 506                 if (ch == EOF)
 507                         break;
 508         }
 509         return (first == 'y' || first == 'Y');
 510 }
 511
 512 #define ISDOT(a)        ((a)[0] == '.' && (!(a)[1] || ((a)[1] == '.' && !(a)[2])))
 513 static void
 514 checkdot(char **argv)
 515 {
 516         char *p, **save, **t;
 517         int complained;
 518
 519         complained = 0;
 520         for (t = argv; *t;) {
 521                 if ((p = strrchr(*t, '/')) != NULL)
 522                         ++p;
 523                 else
 524                         p = *t;
 525                 if (ISDOT(p)) {
 526                         if (!complained++)
 527                                 warnx("\".\" and \"..\" may not be removed");
 528                         eval = 1;
 529                         for (save = t; (t[0] = t[1]) != NULL; ++t)
 530                                 continue;
 531                         t = save;
 532                 } else
 533                         ++t;
 534         }
 535 }
 536
 537 static void
 538 usage(void)
 539 {
 540
 541         (void)fprintf(stderr, "%s\n%s\n",
 542             "usage: rm [-f | -i] [-dIPRrvWx] file ...",
 543             "       unlink [--] file");
 544         exit(EX_USAGE);
 545 }
 546
 547 static void
 548 siginfo(int sig __unused)
 549 {
 550
 551         info = 1;
 552 }