bin/cp/utils.c

   1 /*-
   2  * Copyright (c) 1991, 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  * 4. 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
  30 #ifndef lint
  31 #if 0
  32 static char sccsid[] = "@(#)utils.c     8.3 (Berkeley) 4/1/94";
  33 #endif
  34 #endif /* not lint */
  35 #include <sys/cdefs.h>
  36 __FBSDID("$FreeBSD$");
  37
  38 #include <sys/types.h>
  39 #include <sys/acl.h>
  40 #include <sys/param.h>
  41 #include <sys/stat.h>
  42 #ifdef VM_AND_BUFFER_CACHE_SYNCHRONIZED
  43 #include <sys/mman.h>
  44 #endif
  45
  46 #include <err.h>
  47 #include <errno.h>
  48 #include <fcntl.h>
  49 #include <fts.h>
  50 #include <limits.h>
  51 #include <stdio.h>
  52 #include <stdlib.h>
  53 #include <sysexits.h>
  54 #include <unistd.h>
  55
  56 #include "extern.h"
  57
  58 #define cp_pct(x, y)    ((y == 0) ? 0 : (int)(100.0 * (x) / (y)))
  59
  60 /*
  61  * Memory strategy threshold, in pages: if physmem is larger then this, use a
  62  * large buffer.
  63  */
  64 #define PHYSPAGES_THRESHOLD (32*1024)
  65
  66 /* Maximum buffer size in bytes - do not allow it to grow larger than this. */
  67 #define BUFSIZE_MAX (2*1024*1024)
  68
  69 /*
  70  * Small (default) buffer size in bytes. It's inefficient for this to be
  71  * smaller than MAXPHYS.
  72  */
  73 #define BUFSIZE_SMALL (MAXPHYS)
  74
  75 int
  76 copy_file(const FTSENT *entp, int dne)
  77 {
  78         static char *buf = NULL;
  79         static size_t bufsize;
  80         struct stat *fs;
  81         ssize_t wcount;
  82         size_t wresid;
  83         off_t wtotal;
  84         int ch, checkch, from_fd, rcount, rval, to_fd;
  85         char *bufp;
  86 #ifdef VM_AND_BUFFER_CACHE_SYNCHRONIZED
  87         char *p;
  88 #endif
  89
  90         from_fd = to_fd = -1;
  91         if (!lflag && !sflag &&
  92             (from_fd = open(entp->fts_path, O_RDONLY, 0)) == -1) {
  93                 warn("%s", entp->fts_path);
  94                 return (1);
  95         }
  96
  97         fs = entp->fts_statp;
  98
  99         /*
 100          * If the file exists and we're interactive, verify with the user.
 101          * If the file DNE, set the mode to be the from file, minus setuid
 102          * bits, modified by the umask; arguably wrong, but it makes copying
 103          * executables work right and it's been that way forever.  (The
 104          * other choice is 666 or'ed with the execute bits on the from file
 105          * modified by the umask.)
 106          */
 107         if (!dne) {
 108 #define YESNO "(y/n [n]) "
 109                 if (nflag) {
 110                         if (vflag)
 111                                 printf("%s not overwritten\n", to.p_path);
 112                         rval = 1;
 113                         goto done;
 114                 } else if (iflag) {
 115                         (void)fprintf(stderr, "overwrite %s? %s",
 116                             to.p_path, YESNO);
 117                         checkch = ch = getchar();
 118                         while (ch != '\n' && ch != EOF)
 119                                 ch = getchar();
 120                         if (checkch != 'y' && checkch != 'Y') {
 121                                 (void)fprintf(stderr, "not overwritten\n");
 122                                 rval = 1;
 123                                 goto done;
 124                         }
 125                 }
 126
 127                 if (fflag) {
 128                         /*
 129                          * Remove existing destination file name create a new
 130                          * file.
 131                          */
 132                         (void)unlink(to.p_path);
 133                         if (!lflag && !sflag) {
 134                                 to_fd = open(to.p_path,
 135                                     O_WRONLY | O_TRUNC | O_CREAT,
 136                                     fs->st_mode & ~(S_ISUID | S_ISGID));
 137                         }
 138                 } else if (!lflag && !sflag) {
 139                         /* Overwrite existing destination file name. */
 140                         to_fd = open(to.p_path, O_WRONLY | O_TRUNC, 0);
 141                 }
 142         } else if (!lflag && !sflag) {
 143                 to_fd = open(to.p_path, O_WRONLY | O_TRUNC | O_CREAT,
 144                     fs->st_mode & ~(S_ISUID | S_ISGID));
 145         }
 146
 147         if (!lflag && !sflag && to_fd == -1) {
 148                 warn("%s", to.p_path);
 149                 rval = 1;
 150                 goto done;
 151         }
 152
 153         rval = 0;
 154
 155         if (!lflag && !sflag) {
 156                 /*
 157                  * Mmap and write if less than 8M (the limit is so we don't
 158                  * totally trash memory on big files.  This is really a minor
 159                  * hack, but it wins some CPU back.
 160                  * Some filesystems, such as smbnetfs, don't support mmap,
 161                  * so this is a best-effort attempt.
 162                  */
 163 #ifdef VM_AND_BUFFER_CACHE_SYNCHRONIZED
 164                 if (S_ISREG(fs->st_mode) && fs->st_size > 0 &&
 165                     fs->st_size <= 8 * 1024 * 1024 &&
 166                     (p = mmap(NULL, (size_t)fs->st_size, PROT_READ,
 167                     MAP_SHARED, from_fd, (off_t)0)) != MAP_FAILED) {
 168                         wtotal = 0;
 169                         for (bufp = p, wresid = fs->st_size; ;
 170                             bufp += wcount, wresid -= (size_t)wcount) {
 171                                 wcount = write(to_fd, bufp, wresid);
 172                                 if (wcount <= 0)
 173                                         break;
 174                                 wtotal += wcount;
 175                                 if (info) {
 176                                         info = 0;
 177                                         (void)fprintf(stderr,
 178                                             "%s -> %s %3d%%\n",
 179                                             entp->fts_path, to.p_path,
 180                                             cp_pct(wtotal, fs->st_size));
 181                                 }
 182                                 if (wcount >= (ssize_t)wresid)
 183                                         break;
 184                         }
 185                         if (wcount != (ssize_t)wresid) {
 186                                 warn("%s", to.p_path);
 187                                 rval = 1;
 188                         }
 189                         /* Some systems don't unmap on close(2). */
 190                         if (munmap(p, fs->st_size) < 0) {
 191                                 warn("%s", entp->fts_path);
 192                                 rval = 1;
 193                         }
 194                 } else
 195 #endif
 196                 {
 197                         if (buf == NULL) {
 198                                 /*
 199                                  * Note that buf and bufsize are static. If
 200                                  * malloc() fails, it will fail at the start
 201                                  * and not copy only some files.
 202                                  */
 203                                 if (sysconf(_SC_PHYS_PAGES) >
 204                                     PHYSPAGES_THRESHOLD)
 205                                         bufsize = MIN(BUFSIZE_MAX, MAXPHYS * 8);
 206                                 else
 207                                         bufsize = BUFSIZE_SMALL;
 208                                 buf = malloc(bufsize);
 209                                 if (buf == NULL)
 210                                         err(1, "Not enough memory");
 211                         }
 212                         wtotal = 0;
 213                         while ((rcount = read(from_fd, buf, bufsize)) > 0) {
 214                                 for (bufp = buf, wresid = rcount; ;
 215                                     bufp += wcount, wresid -= wcount) {
 216                                         wcount = write(to_fd, bufp, wresid);
 217                                         if (wcount <= 0)
 218                                                 break;
 219                                         wtotal += wcount;
 220                                         if (info) {
 221                                                 info = 0;
 222                                                 (void)fprintf(stderr,
 223                                                     "%s -> %s %3d%%\n",
 224                                                     entp->fts_path, to.p_path,
 225                                                     cp_pct(wtotal, fs->st_size));
 226                                         }
 227                                         if (wcount >= (ssize_t)wresid)
 228                                                 break;
 229                                 }
 230                                 if (wcount != (ssize_t)wresid) {
 231                                         warn("%s", to.p_path);
 232                                         rval = 1;
 233                                         break;
 234                                 }
 235                         }
 236                         if (rcount < 0) {
 237                                 warn("%s", entp->fts_path);
 238                                 rval = 1;
 239                         }
 240                 }
 241         } else if (lflag) {
 242                 if (link(entp->fts_path, to.p_path)) {
 243                         warn("%s", to.p_path);
 244                         rval = 1;
 245                 }
 246         } else if (sflag) {
 247                 if (symlink(entp->fts_path, to.p_path)) {
 248                         warn("%s", to.p_path);
 249                         rval = 1;
 250                 }
 251         }
 252
 253         /*
 254          * Don't remove the target even after an error.  The target might
 255          * not be a regular file, or its attributes might be important,
 256          * or its contents might be irreplaceable.  It would only be safe
 257          * to remove it if we created it and its length is 0.
 258          */
 259
 260         if (!lflag && !sflag) {
 261                 if (pflag && setfile(fs, to_fd))
 262                         rval = 1;
 263                 if (pflag && preserve_fd_acls(from_fd, to_fd) != 0)
 264                         rval = 1;
 265                 if (close(to_fd)) {
 266                         warn("%s", to.p_path);
 267                         rval = 1;
 268                 }
 269         }
 270
 271 done:
 272         if (from_fd != -1)
 273                 (void)close(from_fd);
 274         return (rval);
 275 }
 276
 277 int
 278 copy_link(const FTSENT *p, int exists)
 279 {
 280         int len;
 281         char llink[PATH_MAX];
 282
 283         if (exists && nflag) {
 284                 if (vflag)
 285                         printf("%s not overwritten\n", to.p_path);
 286                 return (1);
 287         }
 288         if ((len = readlink(p->fts_path, llink, sizeof(llink) - 1)) == -1) {
 289                 warn("readlink: %s", p->fts_path);
 290                 return (1);
 291         }
 292         llink[len] = '\0';
 293         if (exists && unlink(to.p_path)) {
 294                 warn("unlink: %s", to.p_path);
 295                 return (1);
 296         }
 297         if (symlink(llink, to.p_path)) {
 298                 warn("symlink: %s", llink);
 299                 return (1);
 300         }
 301         return (pflag ? setfile(p->fts_statp, -1) : 0);
 302 }
 303
 304 int
 305 copy_fifo(struct stat *from_stat, int exists)
 306 {
 307
 308         if (exists && nflag) {
 309                 if (vflag)
 310                         printf("%s not overwritten\n", to.p_path);
 311                 return (1);
 312         }
 313         if (exists && unlink(to.p_path)) {
 314                 warn("unlink: %s", to.p_path);
 315                 return (1);
 316         }
 317         if (mkfifo(to.p_path, from_stat->st_mode)) {
 318                 warn("mkfifo: %s", to.p_path);
 319                 return (1);
 320         }
 321         return (pflag ? setfile(from_stat, -1) : 0);
 322 }
 323
 324 int
 325 copy_special(struct stat *from_stat, int exists)
 326 {
 327
 328         if (exists && nflag) {
 329                 if (vflag)
 330                         printf("%s not overwritten\n", to.p_path);
 331                 return (1);
 332         }
 333         if (exists && unlink(to.p_path)) {
 334                 warn("unlink: %s", to.p_path);
 335                 return (1);
 336         }
 337         if (mknod(to.p_path, from_stat->st_mode, from_stat->st_rdev)) {
 338                 warn("mknod: %s", to.p_path);
 339                 return (1);
 340         }
 341         return (pflag ? setfile(from_stat, -1) : 0);
 342 }
 343
 344 int
 345 setfile(struct stat *fs, int fd)
 346 {
 347         static struct timespec tspec[2];
 348         struct stat ts;
 349         int rval, gotstat, islink, fdval;
 350
 351         rval = 0;
 352         fdval = fd != -1;
 353         islink = !fdval && S_ISLNK(fs->st_mode);
 354         fs->st_mode &= S_ISUID | S_ISGID | S_ISVTX |
 355             S_IRWXU | S_IRWXG | S_IRWXO;
 356
 357         tspec[0] = fs->st_atim;
 358         tspec[1] = fs->st_mtim;
 359         if (fdval ? futimens(fd, tspec) : utimensat(AT_FDCWD, to.p_path, tspec,
 360             islink ? AT_SYMLINK_NOFOLLOW : 0)) {
 361                 warn("utimensat: %s", to.p_path);
 362                 rval = 1;
 363         }
 364         if (fdval ? fstat(fd, &ts) :
 365             (islink ? lstat(to.p_path, &ts) : stat(to.p_path, &ts)))
 366                 gotstat = 0;
 367         else {
 368                 gotstat = 1;
 369                 ts.st_mode &= S_ISUID | S_ISGID | S_ISVTX |
 370                     S_IRWXU | S_IRWXG | S_IRWXO;
 371         }
 372         /*
 373          * Changing the ownership probably won't succeed, unless we're root
 374          * or POSIX_CHOWN_RESTRICTED is not set.  Set uid/gid before setting
 375          * the mode; current BSD behavior is to remove all setuid bits on
 376          * chown.  If chown fails, lose setuid/setgid bits.
 377          */
 378         if (!gotstat || fs->st_uid != ts.st_uid || fs->st_gid != ts.st_gid)
 379                 if (fdval ? fchown(fd, fs->st_uid, fs->st_gid) :
 380                     (islink ? lchown(to.p_path, fs->st_uid, fs->st_gid) :
 381                     chown(to.p_path, fs->st_uid, fs->st_gid))) {
 382                         if (errno != EPERM) {
 383                                 warn("chown: %s", to.p_path);
 384                                 rval = 1;
 385                         }
 386                         fs->st_mode &= ~(S_ISUID | S_ISGID);
 387                 }
 388
 389         if (!gotstat || fs->st_mode != ts.st_mode)
 390                 if (fdval ? fchmod(fd, fs->st_mode) :
 391                     (islink ? lchmod(to.p_path, fs->st_mode) :
 392                     chmod(to.p_path, fs->st_mode))) {
 393                         warn("chmod: %s", to.p_path);
 394                         rval = 1;
 395                 }
 396
 397         if (!gotstat || fs->st_flags != ts.st_flags)
 398                 if (fdval ?
 399                     fchflags(fd, fs->st_flags) :
 400                     (islink ? lchflags(to.p_path, fs->st_flags) :
 401                     chflags(to.p_path, fs->st_flags))) {
 402                         warn("chflags: %s", to.p_path);
 403                         rval = 1;
 404                 }
 405
 406         return (rval);
 407 }
 408
 409 int
 410 preserve_fd_acls(int source_fd, int dest_fd)
 411 {
 412         acl_t acl;
 413         acl_type_t acl_type;
 414         int acl_supported = 0, ret, trivial;
 415
 416         ret = fpathconf(source_fd, _PC_ACL_NFS4);
 417         if (ret > 0 ) {
 418                 acl_supported = 1;
 419                 acl_type = ACL_TYPE_NFS4;
 420         } else if (ret < 0 && errno != EINVAL) {
 421                 warn("fpathconf(..., _PC_ACL_NFS4) failed for %s", to.p_path);
 422                 return (1);
 423         }
 424         if (acl_supported == 0) {
 425                 ret = fpathconf(source_fd, _PC_ACL_EXTENDED);
 426                 if (ret > 0 ) {
 427                         acl_supported = 1;
 428                         acl_type = ACL_TYPE_ACCESS;
 429                 } else if (ret < 0 && errno != EINVAL) {
 430                         warn("fpathconf(..., _PC_ACL_EXTENDED) failed for %s",
 431                             to.p_path);
 432                         return (1);
 433                 }
 434         }
 435         if (acl_supported == 0)
 436                 return (0);
 437
 438         acl = acl_get_fd_np(source_fd, acl_type);
 439         if (acl == NULL) {
 440                 warn("failed to get acl entries while setting %s", to.p_path);
 441                 return (1);
 442         }
 443         if (acl_is_trivial_np(acl, &trivial)) {
 444                 warn("acl_is_trivial() failed for %s", to.p_path);
 445                 acl_free(acl);
 446                 return (1);
 447         }
 448         if (trivial) {
 449                 acl_free(acl);
 450                 return (0);
 451         }
 452         if (acl_set_fd_np(dest_fd, acl, acl_type) < 0) {
 453                 warn("failed to set acl entries for %s", to.p_path);
 454                 acl_free(acl);
 455                 return (1);
 456         }
 457         acl_free(acl);
 458         return (0);
 459 }
 460
 461 int
 462 preserve_dir_acls(struct stat *fs, char *source_dir, char *dest_dir)
 463 {
 464         acl_t (*aclgetf)(const char *, acl_type_t);
 465         int (*aclsetf)(const char *, acl_type_t, acl_t);
 466         struct acl *aclp;
 467         acl_t acl;
 468         acl_type_t acl_type;
 469         int acl_supported = 0, ret, trivial;
 470
 471         ret = pathconf(source_dir, _PC_ACL_NFS4);
 472         if (ret > 0) {
 473                 acl_supported = 1;
 474                 acl_type = ACL_TYPE_NFS4;
 475         } else if (ret < 0 && errno != EINVAL) {
 476                 warn("fpathconf(..., _PC_ACL_NFS4) failed for %s", source_dir);
 477                 return (1);
 478         }
 479         if (acl_supported == 0) {
 480                 ret = pathconf(source_dir, _PC_ACL_EXTENDED);
 481                 if (ret > 0) {
 482                         acl_supported = 1;
 483                         acl_type = ACL_TYPE_ACCESS;
 484                 } else if (ret < 0 && errno != EINVAL) {
 485                         warn("fpathconf(..., _PC_ACL_EXTENDED) failed for %s",
 486                             source_dir);
 487                         return (1);
 488                 }
 489         }
 490         if (acl_supported == 0)
 491                 return (0);
 492
 493         /*
 494          * If the file is a link we will not follow it.
 495          */
 496         if (S_ISLNK(fs->st_mode)) {
 497                 aclgetf = acl_get_link_np;
 498                 aclsetf = acl_set_link_np;
 499         } else {
 500                 aclgetf = acl_get_file;
 501                 aclsetf = acl_set_file;
 502         }
 503         if (acl_type == ACL_TYPE_ACCESS) {
 504                 /*
 505                  * Even if there is no ACL_TYPE_DEFAULT entry here, a zero
 506                  * size ACL will be returned. So it is not safe to simply
 507                  * check the pointer to see if the default ACL is present.
 508                  */
 509                 acl = aclgetf(source_dir, ACL_TYPE_DEFAULT);
 510                 if (acl == NULL) {
 511                         warn("failed to get default acl entries on %s",
 512                             source_dir);
 513                         return (1);
 514                 }
 515                 aclp = &acl->ats_acl;
 516                 if (aclp->acl_cnt != 0 && aclsetf(dest_dir,
 517                     ACL_TYPE_DEFAULT, acl) < 0) {
 518                         warn("failed to set default acl entries on %s",
 519                             dest_dir);
 520                         acl_free(acl);
 521                         return (1);
 522                 }
 523                 acl_free(acl);
 524         }
 525         acl = aclgetf(source_dir, acl_type);
 526         if (acl == NULL) {
 527                 warn("failed to get acl entries on %s", source_dir);
 528                 return (1);
 529         }
 530         if (acl_is_trivial_np(acl, &trivial)) {
 531                 warn("acl_is_trivial() failed on %s", source_dir);
 532                 acl_free(acl);
 533                 return (1);
 534         }
 535         if (trivial) {
 536                 acl_free(acl);
 537                 return (0);
 538         }
 539         if (aclsetf(dest_dir, acl_type, acl) < 0) {
 540                 warn("failed to set acl entries on %s", dest_dir);
 541                 acl_free(acl);
 542                 return (1);
 543         }
 544         acl_free(acl);
 545         return (0);
 546 }
 547
 548 void
 549 usage(void)
 550 {
 551
 552         (void)fprintf(stderr, "%s\n%s\n",
 553             "usage: cp [-R [-H | -L | -P]] [-f | -i | -n] [-alpsvx] "
 554             "source_file target_file",
 555             "       cp [-R [-H | -L | -P]] [-f | -i | -n] [-alpsvx] "
 556             "source_file ... "
 557             "target_directory");
 558         exit(EX_USAGE);
 559 }