utils.c revision 297782
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 32static char sccsid[] = "@(#)utils.c 8.3 (Berkeley) 4/1/94"; 33#endif 34#endif /* not lint */ 35#include <sys/cdefs.h> 36__FBSDID("$FreeBSD: stable/10/bin/cp/utils.c 297782 2016-04-10 15:02:29Z jilles $"); 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 75int 76copy_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 271done: 272 if (from_fd != -1) 273 (void)close(from_fd); 274 return (rval); 275} 276 277int 278copy_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 304int 305copy_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 324int 325copy_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 344int 345setfile(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 (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 409int 410preserve_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 461int 462preserve_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 548void 549usage(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} 560