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 <stdio.h>
  58 #include <stdlib.h>
  59 #include <string.h>
  60 #include <sysexits.h>
  61 #include <unistd.h>
  62
  63 static int dflag, eval, fflag, iflag, vflag, Wflag, stdin_ok;
  64 static int rflag, Iflag, xflag;
  65 static uid_t uid;
  66 static volatile sig_atomic_t info;
  67
  68 static int      check(const char *, const char *, struct stat *);
  69 static int      check2(char **);
  70 static void     checkdot(char **);
  71 static void     checkslash(char **);
  72 static void     rm_file(char **);
  73 static void     rm_tree(char **);
  74 static void siginfo(int __unused);
  75 static void     usage(void);
  76
  77 /*
  78  * rm --
  79  *      This rm is different from historic rm's, but is expected to match
  80  *      POSIX 1003.2 behavior.  The most visible difference is that -f
  81  *      has two specific effects now, ignore non-existent files and force
  82  *      file removal.
  83  */
  84 int
  85 main(int argc, char *argv[])
  86 {
  87         int ch;
  88         char *p;
  89
  90         (void)setlocale(LC_ALL, "");
  91
  92         /*
  93          * Test for the special case where the utility is called as
  94          * "unlink", for which the functionality provided is greatly
  95          * simplified.
  96          */
  97         if ((p = strrchr(argv[0], '/')) == NULL)
  98                 p = argv[0];
  99         else
 100                 ++p;
 101         if (strcmp(p, "unlink") == 0) {
 102                 if (argc == 2)
 103                         rm_file(&argv[1]);
 104                 else if (argc == 3 && strcmp(argv[1], "--") == 0)
 105                         rm_file(&argv[2]);
 106                 else
 107                         usage();
 108                 exit(eval);
 109         }
 110
 111         rflag = xflag = 0;
 112         while ((ch = getopt(argc, argv, "dfiIPRrvWx")) != -1)
 113                 switch(ch) {
 114                 case 'd':
 115                         dflag = 1;
 116                         break;
 117                 case 'f':
 118                         fflag = 1;
 119                         iflag = 0;
 120                         break;
 121                 case 'i':
 122                         fflag = 0;
 123                         iflag = 1;
 124                         break;
 125                 case 'I':
 126                         Iflag = 1;
 127                         break;
 128                 case 'P':
 129                         /* Compatibility no-op. */
 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                         Wflag = 1;
 140                         break;
 141                 case 'x':
 142                         xflag = 1;
 143                         break;
 144                 default:
 145                         usage();
 146                 }
 147         argc -= optind;
 148         argv += optind;
 149
 150         if (argc < 1) {
 151                 if (fflag)
 152                         return (0);
 153                 usage();
 154         }
 155
 156         checkdot(argv);
 157         checkslash(argv);
 158         uid = geteuid();
 159
 160         (void)signal(SIGINFO, siginfo);
 161         if (*argv) {
 162                 stdin_ok = isatty(STDIN_FILENO);
 163
 164                 if (Iflag) {
 165                         if (check2(argv) == 0)
 166                                 exit (1);
 167                 }
 168                 if (rflag)
 169                         rm_tree(argv);
 170                 else
 171                         rm_file(argv);
 172         }
 173
 174         exit (eval);
 175 }
 176
 177 static void
 178 rm_tree(char **argv)
 179 {
 180         FTS *fts;
 181         FTSENT *p;
 182         int needstat;
 183         int flags;
 184         int rval;
 185
 186         /*
 187          * Remove a file hierarchy.  If forcing removal (-f), or interactive
 188          * (-i) or can't ask anyway (stdin_ok), don't stat the file.
 189          */
 190         needstat = !uid || (!fflag && !iflag && stdin_ok);
 191
 192         /*
 193          * If the -i option is specified, the user can skip on the pre-order
 194          * visit.  The fts_number field flags skipped directories.
 195          */
 196 #define SKIPPED 1
 197
 198         flags = FTS_PHYSICAL;
 199         if (!needstat)
 200                 flags |= FTS_NOSTAT;
 201         if (Wflag)
 202                 flags |= FTS_WHITEOUT;
 203         if (xflag)
 204                 flags |= FTS_XDEV;
 205         if (!(fts = fts_open(argv, flags, NULL))) {
 206                 if (fflag && errno == ENOENT)
 207                         return;
 208                 err(1, "fts_open");
 209         }
 210         while (errno = 0, (p = fts_read(fts)) != NULL) {
 211                 switch (p->fts_info) {
 212                 case FTS_DNR:
 213                         if (!fflag || p->fts_errno != ENOENT) {
 214                                 warnx("%s: %s",
 215                                     p->fts_path, strerror(p->fts_errno));
 216                                 eval = 1;
 217                         }
 218                         continue;
 219                 case FTS_ERR:
 220                         errx(1, "%s: %s", p->fts_path, strerror(p->fts_errno));
 221                 case FTS_NS:
 222                         /*
 223                          * Assume that since fts_read() couldn't stat the
 224                          * file, it can't be unlinked.
 225                          */
 226                         if (!needstat)
 227                                 break;
 228                         if (!fflag || p->fts_errno != ENOENT) {
 229                                 warnx("%s: %s",
 230                                     p->fts_path, strerror(p->fts_errno));
 231                                 eval = 1;
 232                         }
 233                         continue;
 234                 case FTS_D:
 235                         /* Pre-order: give user chance to skip. */
 236                         if (!fflag && !check(p->fts_path, p->fts_accpath,
 237                             p->fts_statp)) {
 238                                 (void)fts_set(fts, p, FTS_SKIP);
 239                                 p->fts_number = SKIPPED;
 240                         }
 241                         else if (!uid &&
 242                                  (p->fts_statp->st_flags & (UF_APPEND|UF_IMMUTABLE)) &&
 243                                  !(p->fts_statp->st_flags & (SF_APPEND|SF_IMMUTABLE)) &&
 244                                  lchflags(p->fts_accpath,
 245                                          p->fts_statp->st_flags &= ~(UF_APPEND|UF_IMMUTABLE)) < 0)
 246                                 goto err;
 247                         continue;
 248                 case FTS_DP:
 249                         /* Post-order: see if user skipped. */
 250                         if (p->fts_number == SKIPPED)
 251                                 continue;
 252                         break;
 253                 default:
 254                         if (!fflag &&
 255                             !check(p->fts_path, p->fts_accpath, p->fts_statp))
 256                                 continue;
 257                 }
 258
 259                 rval = 0;
 260                 if (!uid &&
 261                     (p->fts_statp->st_flags & (UF_APPEND|UF_IMMUTABLE)) &&
 262                     !(p->fts_statp->st_flags & (SF_APPEND|SF_IMMUTABLE)))
 263                         rval = lchflags(p->fts_accpath,
 264                                        p->fts_statp->st_flags &= ~(UF_APPEND|UF_IMMUTABLE));
 265                 if (rval == 0) {
 266                         /*
 267                          * If we can't read or search the directory, may still be
 268                          * able to remove it.  Don't print out the un{read,search}able
 269                          * message unless the remove fails.
 270                          */
 271                         switch (p->fts_info) {
 272                         case FTS_DP:
 273                         case FTS_DNR:
 274                                 rval = rmdir(p->fts_accpath);
 275                                 if (rval == 0 || (fflag && errno == ENOENT)) {
 276                                         if (rval == 0 && vflag)
 277                                                 (void)printf("%s\n",
 278                                                     p->fts_path);
 279                                         if (rval == 0 && info) {
 280                                                 info = 0;
 281                                                 (void)printf("%s\n",
 282                                                     p->fts_path);
 283                                         }
 284                                         continue;
 285                                 }
 286                                 break;
 287
 288                         case FTS_W:
 289                                 rval = undelete(p->fts_accpath);
 290                                 if (rval == 0 && (fflag && errno == ENOENT)) {
 291                                         if (vflag)
 292                                                 (void)printf("%s\n",
 293                                                     p->fts_path);
 294                                         if (info) {
 295                                                 info = 0;
 296                                                 (void)printf("%s\n",
 297                                                     p->fts_path);
 298                                         }
 299                                         continue;
 300                                 }
 301                                 break;
 302
 303                         case FTS_NS:
 304                                 /*
 305                                  * Assume that since fts_read() couldn't stat
 306                                  * the file, it can't be unlinked.
 307                                  */
 308                                 if (fflag)
 309                                         continue;
 310                                 /* FALLTHROUGH */
 311
 312                         case FTS_F:
 313                         case FTS_NSOK:
 314                         default:
 315                                 rval = unlink(p->fts_accpath);
 316                                 if (rval == 0 || (fflag && errno == ENOENT)) {
 317                                         if (rval == 0 && vflag)
 318                                                 (void)printf("%s\n",
 319                                                     p->fts_path);
 320                                         if (rval == 0 && info) {
 321                                                 info = 0;
 322                                                 (void)printf("%s\n",
 323                                                     p->fts_path);
 324                                         }
 325                                         continue;
 326                                 }
 327                         }
 328                 }
 329 err:
 330                 warn("%s", p->fts_path);
 331                 eval = 1;
 332         }
 333         if (!fflag && errno)
 334                 err(1, "fts_read");
 335         fts_close(fts);
 336 }
 337
 338 static void
 339 rm_file(char **argv)
 340 {
 341         struct stat sb;
 342         int rval;
 343         char *f;
 344
 345         /*
 346          * Remove a file.  POSIX 1003.2 states that, by default, attempting
 347          * to remove a directory is an error, so must always stat the file.
 348          */
 349         while ((f = *argv++) != NULL) {
 350                 /* Assume if can't stat the file, can't unlink it. */
 351                 if (lstat(f, &sb)) {
 352                         if (Wflag) {
 353                                 sb.st_mode = S_IFWHT|S_IWUSR|S_IRUSR;
 354                         } else {
 355                                 if (!fflag || errno != ENOENT) {
 356                                         warn("%s", f);
 357                                         eval = 1;
 358                                 }
 359                                 continue;
 360                         }
 361                 } else if (Wflag) {
 362                         warnx("%s: %s", f, strerror(EEXIST));
 363                         eval = 1;
 364                         continue;
 365                 }
 366
 367                 if (S_ISDIR(sb.st_mode) && !dflag) {
 368                         warnx("%s: is a directory", f);
 369                         eval = 1;
 370                         continue;
 371                 }
 372                 if (!fflag && !S_ISWHT(sb.st_mode) && !check(f, f, &sb))
 373                         continue;
 374                 rval = 0;
 375                 if (!uid && !S_ISWHT(sb.st_mode) &&
 376                     (sb.st_flags & (UF_APPEND|UF_IMMUTABLE)) &&
 377                     !(sb.st_flags & (SF_APPEND|SF_IMMUTABLE)))
 378                         rval = lchflags(f, sb.st_flags & ~(UF_APPEND|UF_IMMUTABLE));
 379                 if (rval == 0) {
 380                         if (S_ISWHT(sb.st_mode))
 381                                 rval = undelete(f);
 382                         else if (S_ISDIR(sb.st_mode))
 383                                 rval = rmdir(f);
 384                         else
 385                                 rval = unlink(f);
 386                 }
 387                 if (rval && (!fflag || errno != ENOENT)) {
 388                         warn("%s", f);
 389                         eval = 1;
 390                 }
 391                 if (vflag && rval == 0)
 392                         (void)printf("%s\n", f);
 393                 if (info && rval == 0) {
 394                         info = 0;
 395                         (void)printf("%s\n", f);
 396                 }
 397         }
 398 }
 399
 400 static int
 401 check(const char *path, const char *name, struct stat *sp)
 402 {
 403         int ch, first;
 404         char modep[15], *flagsp;
 405
 406         /* Check -i first. */
 407         if (iflag)
 408                 (void)fprintf(stderr, "remove %s? ", path);
 409         else {
 410                 /*
 411                  * If it's not a symbolic link and it's unwritable and we're
 412                  * talking to a terminal, ask.  Symbolic links are excluded
 413                  * because their permissions are meaningless.  Check stdin_ok
 414                  * first because we may not have stat'ed the file.
 415                  */
 416                 if (!stdin_ok || S_ISLNK(sp->st_mode) ||
 417                     (!access(name, W_OK) &&
 418                     !(sp->st_flags & (SF_APPEND|SF_IMMUTABLE)) &&
 419                     (!(sp->st_flags & (UF_APPEND|UF_IMMUTABLE)) || !uid)))
 420                         return (1);
 421                 strmode(sp->st_mode, modep);
 422                 if ((flagsp = fflagstostr(sp->st_flags)) == NULL)
 423                         err(1, "fflagstostr");
 424                 (void)fprintf(stderr, "override %s%s%s/%s %s%sfor %s? ",
 425                     modep + 1, modep[10] == ' ' ? "" : " ",
 426                     user_from_uid(sp->st_uid, 0),
 427                     group_from_gid(sp->st_gid, 0),
 428                     *flagsp ? flagsp : "", *flagsp ? " " : "",
 429                     path);
 430                 free(flagsp);
 431         }
 432         (void)fflush(stderr);
 433
 434         first = ch = getchar();
 435         while (ch != '\n' && ch != EOF)
 436                 ch = getchar();
 437         return (first == 'y' || first == 'Y');
 438 }
 439
 440 #define ISSLASH(a)      ((a)[0] == '/' && (a)[1] == '\0')
 441 static void
 442 checkslash(char **argv)
 443 {
 444         char **t, **u;
 445         int complained;
 446
 447         complained = 0;
 448         for (t = argv; *t;) {
 449                 if (ISSLASH(*t)) {
 450                         if (!complained++)
 451                                 warnx("\"/\" may not be removed");
 452                         eval = 1;
 453                         for (u = t; u[0] != NULL; ++u)
 454                                 u[0] = u[1];
 455                 } else {
 456                         ++t;
 457                 }
 458         }
 459 }
 460
 461 static int
 462 check2(char **argv)
 463 {
 464         struct stat st;
 465         int first;
 466         int ch;
 467         int fcount = 0;
 468         int dcount = 0;
 469         int i;
 470         const char *dname = NULL;
 471
 472         for (i = 0; argv[i]; ++i) {
 473                 if (lstat(argv[i], &st) == 0) {
 474                         if (S_ISDIR(st.st_mode)) {
 475                                 ++dcount;
 476                                 dname = argv[i];    /* only used if 1 dir */
 477                         } else {
 478                                 ++fcount;
 479                         }
 480                 }
 481         }
 482         first = 0;
 483         while (first != 'n' && first != 'N' && first != 'y' && first != 'Y') {
 484                 if (dcount && rflag) {
 485                         fprintf(stderr, "recursively remove");
 486                         if (dcount == 1)
 487                                 fprintf(stderr, " %s", dname);
 488                         else
 489                                 fprintf(stderr, " %d dirs", dcount);
 490                         if (fcount == 1)
 491                                 fprintf(stderr, " and 1 file");
 492                         else if (fcount > 1)
 493                                 fprintf(stderr, " and %d files", fcount);
 494                 } else if (dcount + fcount > 3) {
 495                         fprintf(stderr, "remove %d files", dcount + fcount);
 496                 } else {
 497                         return(1);
 498                 }
 499                 fprintf(stderr, "? ");
 500                 fflush(stderr);
 501
 502                 first = ch = getchar();
 503                 while (ch != '\n' && ch != EOF)
 504                         ch = getchar();
 505                 if (ch == EOF)
 506                         break;
 507         }
 508         return (first == 'y' || first == 'Y');
 509 }
 510
 511 #define ISDOT(a)        ((a)[0] == '.' && (!(a)[1] || ((a)[1] == '.' && !(a)[2])))
 512 static void
 513 checkdot(char **argv)
 514 {
 515         char *p, **save, **t;
 516         int complained;
 517
 518         complained = 0;
 519         for (t = argv; *t;) {
 520                 if ((p = strrchr(*t, '/')) != NULL)
 521                         ++p;
 522                 else
 523                         p = *t;
 524                 if (ISDOT(p)) {
 525                         if (!complained++)
 526                                 warnx("\".\" and \"..\" may not be removed");
 527                         eval = 1;
 528                         for (save = t; (t[0] = t[1]) != NULL; ++t)
 529                                 continue;
 530                         t = save;
 531                 } else
 532                         ++t;
 533         }
 534 }
 535
 536 static void
 537 usage(void)
 538 {
 539
 540         (void)fprintf(stderr, "%s\n%s\n",
 541             "usage: rm [-f | -i] [-dIPRrvWx] file ...",
 542             "       unlink [--] file");
 543         exit(EX_USAGE);
 544 }
 545
 546 static void
 547 siginfo(int sig __unused)
 548 {
 549
 550         info = 1;
 551 }