1/* $OpenBSD: file_subs.c,v 1.30 2005/11/09 19:59:06 otto Exp $ */ 2/* $NetBSD: file_subs.c,v 1.4 1995/03/21 09:07:18 cgd Exp $ */ 3 4/*- 5 * Copyright (c) 1992 Keith Muller. 6 * Copyright (c) 1992, 1993 7 * The Regents of the University of California. All rights reserved. 8 * 9 * This code is derived from software contributed to Berkeley by 10 * Keith Muller of the University of California, San Diego. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37#ifndef lint 38#if 0 39static const char sccsid[] = "@(#)file_subs.c 8.1 (Berkeley) 5/31/93"; 40#else 41static const char rcsid[] = "$OpenBSD: file_subs.c,v 1.30 2005/11/09 19:59:06 otto Exp $"; 42#endif 43#endif /* not lint */ 44 45#include <sys/param.h> 46#include <sys/time.h> 47#include <sys/stat.h> 48#include <sys/uio.h> 49#include <err.h> 50#include <errno.h> 51#include <fcntl.h> 52#include <stdio.h> 53#include <stdlib.h> 54#include <string.h> 55#include <unistd.h> 56#include "pax.h" 57#include "options.h" 58#include "extern.h" 59 60static int 61mk_link(char *, struct stat *, char *, int); 62 63/* 64 * routines that deal with file operations such as: creating, removing; 65 * and setting access modes, uid/gid and times of files 66 */ 67 68#define FILEBITS (S_ISVTX | S_IRWXU | S_IRWXG | S_IRWXO) 69#define SETBITS (S_ISUID | S_ISGID) 70#define ABITS (FILEBITS | SETBITS) 71 72/* 73 * file_creat() 74 * Create and open a file. 75 * Return: 76 * file descriptor or -1 for failure 77 */ 78 79int 80file_creat(ARCHD *arcn) 81{ 82 int fd = -1; 83 mode_t file_mode; 84 int oerrno; 85 int rc = 0; 86 char *path_to_open; 87 char *new_path; 88 char *cwd; 89 char cwd_buff[MAXPATHLEN]; 90 91 /* 92 * Assume file doesn't exist, so just try to create it, most times this 93 * works. We have to take special handling when the file does exist. To 94 * detect this, we use O_EXCL. For example when trying to create a 95 * file and a character device or fifo exists with the same name, we 96 * can accidently open the device by mistake (or block waiting to open). 97 * If we find that the open has failed, then spend the effort to 98 * figure out why. This strategy was found to have better average 99 * performance in common use than checking the file (and the path) 100 * first with lstat. 101 */ 102 file_mode = arcn->sb.st_mode & FILEBITS; 103 if ((fd = open(arcn->name, O_WRONLY | O_CREAT | O_TRUNC | O_EXCL, 104 file_mode)) >= 0) 105 return(fd); 106 107 /* 108 * the file seems to exist. First we try to get rid of it (found to be 109 * the second most common failure when traced). If this fails, only 110 * then we go to the expense to check and create the path to the file 111 */ 112 if (unlnk_exist(arcn->name, arcn->type) != 0) 113 return(-1); 114 115 path_to_open = arcn->name; 116 new_path = arcn->name; 117 cwd = getcwd(&cwd_buff[0],MAXPATHLEN); 118 if (cwd==NULL) return -1; 119 for (;;) { 120 /* 121 * try to open it again, if this fails, check all the nodes in 122 * the path and give it a final try. if chk_path() finds that 123 * it cannot fix anything, we will skip the last attempt 124 */ 125 if ((fd = open(path_to_open, O_WRONLY | O_CREAT | O_TRUNC, 126 file_mode)) >= 0) { 127 /* clean up the invalid_action */ 128 if (pax_invalid_action>0) { 129 record_pax_invalid_action_results(arcn, path_to_open); 130 } 131 break; 132 } 133 oerrno = errno; 134 if (pax_invalid_action>0) { 135 rc = perform_pax_invalid_action(arcn, oerrno); 136 if (rc == 0) continue; 137 if (rc == 1) { 138 fd = -1; 139 break; 140 } 141 } 142 /* rc == 2 reserved for -o invalid_action=write */ 143 if (nodirs || chk_path(path_to_open,arcn->sb.st_uid,arcn->sb.st_gid, 144 (rc==2) ? &new_path: NULL) < 0) { 145 syswarn((pax_invalid_action==0), oerrno, "Unable to create %s", arcn->name); 146 fd = -1; 147 break; 148 } 149 if (new_path) path_to_open = new_path; /* try again */ 150 } 151 if (strcmp(new_path, arcn->name)!=0) { 152 dochdir(cwd); /* go back to original directory */ 153 } 154 return(fd); 155} 156 157/* 158 * file_close() 159 * Close file descriptor to a file just created by pax. Sets modes, 160 * ownership and times as required. 161 * Return: 162 * 0 for success, -1 for failure 163 */ 164 165void 166file_close(ARCHD *arcn, int fd) 167{ 168 int res = 0; 169 170 if (fd < 0) 171 return; 172 173 if (close(fd) < 0) 174 syswarn(0, errno, "Unable to close file descriptor on %s", 175 arcn->name); 176 177 /* 178 * set owner/groups first as this may strip off mode bits we want 179 * then set file permission modes. Then set file access and 180 * modification times. 181 */ 182 if (pids) 183 res = set_ids(arcn->name, arcn->sb.st_uid, 184 arcn->sb.st_gid); 185 else 186 res = 1; /* without pids, pax should NOT set s bits */ 187 188 /* 189 * IMPORTANT SECURITY NOTE: 190 * if not preserving mode or we cannot set uid/gid, then PROHIBIT 191 * set uid/gid bits 192 */ 193 if (!pmode || res) 194 arcn->sb.st_mode &= ~(SETBITS); 195 if (pmode) 196 set_pmode(arcn->name, arcn->sb.st_mode); 197 if (patime || pmtime) 198 set_ftime(arcn->name, arcn->sb.st_mtime, arcn->sb.st_atime, 0); 199} 200 201/* 202 * lnk_creat() 203 * Create a hard link to arcn->ln_name from arcn->name. arcn->ln_name 204 * must exist; 205 * Return: 206 * 0 if ok, -1 otherwise 207 */ 208 209int 210lnk_creat(ARCHD *arcn) 211{ 212 struct stat sb; 213 214 /* 215 * we may be running as root, so we have to be sure that link target 216 * is not a directory, so we lstat and check 217 */ 218 if (lstat(arcn->ln_name, &sb) < 0) { 219 syswarn(1,errno,"Unable to link to %s from %s", arcn->ln_name, 220 arcn->name); 221 return(-1); 222 } 223 224 if (S_ISDIR(sb.st_mode)) { 225 paxwarn(1, "A hard link to the directory %s is not allowed", 226 arcn->ln_name); 227 return(-1); 228 } 229 230 if (S_ISLNK(sb.st_mode)) { 231 int res; 232 char buff[PATH_MAX+1]; 233 /* 234 * Conformance: cannot make hard link to symlink - just make a 235 * symlink to the target of the symlink 236 */ 237 if ((res = readlink(arcn->ln_name, buff, sizeof(buff)-1)) < 0) { 238 syswarn(1,errno,"Unable to symlink to %s from %s", arcn->ln_name, 239 arcn->name); 240 return(-1); 241 } 242 buff[res] = 0; 243 res = symlink(buff, arcn->name); 244 return res; 245 } 246 247 return(mk_link(arcn->ln_name, &sb, arcn->name, 0)); 248} 249 250/* 251 * cross_lnk() 252 * Create a hard link to arcn->org_name from arcn->name. Only used in copy 253 * with the -l flag. No warning or error if this does not succeed (we will 254 * then just create the file) 255 * Return: 256 * 1 if copy() should try to create this file node 257 * 0 if cross_lnk() ok, -1 for fatal flaw (like linking to self). 258 */ 259 260int 261cross_lnk(ARCHD *arcn) 262{ 263 /* 264 * try to make a link to original file (-l flag in copy mode). make 265 * sure we do not try to link to directories in case we are running as 266 * root (and it might succeed). 267 */ 268 if (arcn->type == PAX_DIR) 269 return(1); 270 if (arcn->type == PAX_SLK) { /* for Unix 03 conformance tests 202,203 */ 271 if (!Lflag) 272 return(1); 273 } 274 return(mk_link(arcn->org_name, &(arcn->sb), arcn->name, 1)); 275} 276 277/* 278 * chk_same() 279 * In copy mode if we are not trying to make hard links between the src 280 * and destinations, make sure we are not going to overwrite ourselves by 281 * accident. This slows things down a little, but we have to protect all 282 * those people who make typing errors. 283 * Return: 284 * 1 the target does not exist, go ahead and copy 285 * 0 skip it file exists (-k) or may be the same as source file 286 */ 287 288int 289chk_same(ARCHD *arcn) 290{ 291 struct stat sb; 292 293 /* 294 * if file does not exist, return. if file exists and -k, skip it 295 * quietly 296 */ 297 if (lstat(arcn->name, &sb) < 0) 298 return(1); 299 if (kflag) 300 return(0); 301 302 /* 303 * better make sure the user does not have src == dest by mistake 304 */ 305 if ((arcn->sb.st_dev == sb.st_dev) && (arcn->sb.st_ino == sb.st_ino)) { 306 paxwarn(1, "Unable to copy %s, file would overwrite itself", 307 arcn->name); 308 return(0); 309 } 310 return(1); 311} 312 313/* 314 * mk_link() 315 * try to make a hard link between two files. if ign set, we do not 316 * complain. 317 * Return: 318 * 0 if successful (or we are done with this file but no error, such as 319 * finding the from file exists and the user has set -k). 320 * 1 when ign was set to indicates we could not make the link but we 321 * should try to copy/extract the file as that might work (and is an 322 * allowed option). -1 an error occurred. 323 */ 324 325static int 326mk_link(char *to, struct stat *to_sb, char *from, int ign) 327{ 328 struct stat sb; 329 int oerrno; 330 331 /* 332 * if from file exists, it has to be unlinked to make the link. If the 333 * file exists and -k is set, skip it quietly 334 */ 335 if (lstat(from, &sb) == 0) { 336 if (kflag) 337 return(0); 338 339 /* 340 * make sure it is not the same file, protect the user 341 */ 342 if ((to_sb->st_dev==sb.st_dev)&&(to_sb->st_ino == sb.st_ino)) { 343 paxwarn(1, "Unable to link file %s to itself", to); 344 return(-1); 345 } 346 347 /* 348 * try to get rid of the file, based on the type 349 */ 350 if (S_ISDIR(sb.st_mode)) { 351 if (rmdir(from) < 0) { 352 syswarn(1, errno, "Unable to remove %s", from); 353 return(-1); 354 } 355 } else if (unlink(from) < 0) { 356 if (!ign) { 357 syswarn(1, errno, "Unable to remove %s", from); 358 return(-1); 359 } 360 return(1); 361 } 362 } 363 364 /* 365 * from file is gone (or did not exist), try to make the hard link. 366 * if it fails, check the path and try it again (if chk_path() says to 367 * try again) 368 */ 369 for (;;) { 370 if (link(to, from) == 0) 371 break; 372 oerrno = errno; 373 if (!nodirs && chk_path(from, to_sb->st_uid, to_sb->st_gid, NULL) == 0) 374 continue; 375 if (!ign) { 376 syswarn(1, oerrno, "Could not link to %s from %s", to, 377 from); 378 return(-1); 379 } 380 return(1); 381 } 382 383 /* 384 * all right the link was made 385 */ 386 return(0); 387} 388 389/* 390 * node_creat() 391 * create an entry in the file system (other than a file or hard link). 392 * If successful, sets uid/gid modes and times as required. 393 * Return: 394 * 0 if ok, -1 otherwise 395 */ 396 397int 398node_creat(ARCHD *arcn) 399{ 400 int res; 401 int ign = 0; 402 int oerrno; 403 int pass = 0; 404 mode_t file_mode; 405 struct stat sb; 406 char target[MAXPATHLEN]; 407 char *nm = arcn->name; 408 int nmlen = arcn->nlen; 409 int len; 410 411 /* 412 * create node based on type, if that fails try to unlink the node and 413 * try again. finally check the path and try again. As noted in the 414 * file and link creation routines, this method seems to exhibit the 415 * best performance in general use workloads. 416 */ 417 file_mode = arcn->sb.st_mode & FILEBITS; 418 419 for (;;) { 420 switch (arcn->type) { 421 case PAX_DIR: 422 /* 423 * If -h (or -L) was given in tar-mode, follow the 424 * potential symlink chain before trying to create the 425 * directory. 426 */ 427 if (strcmp(NM_TAR, argv0) == 0 && Lflag) { 428 while (lstat(nm, &sb) == 0 && 429 S_ISLNK(sb.st_mode)) { 430 len = readlink(nm, target, 431 sizeof target - 1); 432 if (len == -1) { 433 syswarn(0, errno, 434 "cannot follow symlink %s in chain for %s", 435 nm, arcn->name); 436 res = -1; 437 goto badlink; 438 } 439 target[len] = '\0'; 440 nm = target; 441 nmlen = len; 442 } 443 } 444 res = mkdir(nm, file_mode); 445 446badlink: 447 if (ign) 448 res = 0; 449 break; 450 case PAX_CHR: 451 file_mode |= S_IFCHR; 452 res = mknod(nm, file_mode, arcn->sb.st_rdev); 453 break; 454 case PAX_BLK: 455 file_mode |= S_IFBLK; 456 res = mknod(nm, file_mode, arcn->sb.st_rdev); 457 break; 458 case PAX_FIF: 459 res = mkfifo(nm, file_mode); 460 break; 461 case PAX_SCK: 462 /* 463 * Skip sockets, operation has no meaning under BSD 464 */ 465 paxwarn(0, 466 "%s skipped. Sockets cannot be copied or extracted", 467 nm); 468 return(-1); 469 case PAX_SLK: 470 res = symlink(arcn->ln_name, nm); 471 break; 472 case PAX_CTG: 473 case PAX_HLK: 474 case PAX_HRG: 475 case PAX_REG: 476 default: 477 /* 478 * we should never get here 479 */ 480 paxwarn(0, "%s has an unknown file type, skipping", 481 nm); 482 return(-1); 483 } 484 485 /* 486 * if we were able to create the node break out of the loop, 487 * otherwise try to unlink the node and try again. if that 488 * fails check the full path and try a final time. 489 */ 490 if (res == 0) 491 break; 492 493 /* 494 * we failed to make the node 495 */ 496 oerrno = errno; 497 if ((ign = unlnk_exist(nm, arcn->type)) < 0) 498 return(-1); 499 500 if (++pass <= 1) 501 continue; 502 503 if (nodirs || chk_path(nm,arcn->sb.st_uid,arcn->sb.st_gid, NULL) < 0) { 504 syswarn(1, oerrno, "Could not create: %s", nm); 505 return(-1); 506 } 507 } 508 509 /* 510 * we were able to create the node. set uid/gid, modes and times 511 */ 512 if (pids) 513 res = ((arcn->type == PAX_SLK) ? 514#if defined(__APPLE__) 515 /* Mac OS X doesn't have lchown, so don't bother */ 516 0 : 517#else 518 set_lids(nm, arcn->sb.st_uid, arcn->sb.st_gid) : 519#endif 520 set_ids(nm, arcn->sb.st_uid, arcn->sb.st_gid)); 521 else 522 res = 1; /* without pids, pax should NOT set s bits */ 523 524 /* 525 * symlinks are done now. 526 */ 527 if (arcn->type == PAX_SLK) 528 return(0); 529 530 /* 531 * IMPORTANT SECURITY NOTE: 532 * if not preserving mode or we cannot set uid/gid, then PROHIBIT any 533 * set uid/gid bits 534 */ 535 if (!pmode || res) 536 arcn->sb.st_mode &= ~(SETBITS); 537 if (pmode) 538 set_pmode(nm, arcn->sb.st_mode); 539 540 if (arcn->type == PAX_DIR && strcmp(NM_CPIO, argv0) != 0) { 541 /* 542 * Dirs must be processed again at end of extract to set times 543 * and modes to agree with those stored in the archive. However 544 * to allow extract to continue, we may have to also set owner 545 * rights. This allows nodes in the archive that are children 546 * of this directory to be extracted without failure. Both time 547 * and modes will be fixed after the entire archive is read and 548 * before pax exits. 549 */ 550 if (access(nm, R_OK | W_OK | X_OK) < 0) { 551 if (lstat(nm, &sb) < 0) { 552 syswarn(0, errno,"Could not access %s (stat)", 553 arcn->name); 554 set_pmode(nm,file_mode | S_IRWXU); 555 } else { 556 /* 557 * We have to add rights to the dir, so we make 558 * sure to restore the mode. The mode must be 559 * restored AS CREATED and not as stored if 560 * pmode is not set. 561 */ 562 set_pmode(nm, 563 ((sb.st_mode & FILEBITS) | S_IRWXU)); 564 if (!pmode) 565 arcn->sb.st_mode = sb.st_mode; 566 } 567 568 /* 569 * we have to force the mode to what was set here, 570 * since we changed it from the default as created. 571 */ 572 add_dir(nm, nmlen, &(arcn->sb), 1); 573 } else if (pmode || patime || pmtime) 574 add_dir(nm, nmlen, &(arcn->sb), 0); 575 } 576 577 if (patime || pmtime) 578 set_ftime(nm, arcn->sb.st_mtime, arcn->sb.st_atime, 0); 579 return(0); 580} 581 582/* 583 * unlnk_exist() 584 * Remove node from file system with the specified name. We pass the type 585 * of the node that is going to replace it. When we try to create a 586 * directory and find that it already exists, we allow processing to 587 * continue as proper modes etc will always be set for it later on. 588 * Return: 589 * 0 is ok to proceed, no file with the specified name exists 590 * -1 we were unable to remove the node, or we should not remove it (-k) 591 * 1 we found a directory and we were going to create a directory. 592 */ 593 594int 595unlnk_exist(char *name, int type) 596{ 597 struct stat sb; 598 599 /* 600 * the file does not exist, or -k we are done 601 */ 602 if (lstat(name, &sb) < 0) 603 return(0); 604 if (kflag) 605 return(-1); 606 607 if(strstr(name, "._") != NULL) /* remove when stat works properly */ 608 return(0); 609 610 if (S_ISDIR(sb.st_mode)) { 611 /* 612 * try to remove a directory, if it fails and we were going to 613 * create a directory anyway, tell the caller (return a 1) 614 */ 615 if (rmdir(name) < 0) { 616 if (type == PAX_DIR) 617 return(1); 618 syswarn(1,errno,"Unable to remove directory %s", name); 619 return(-1); 620 } 621 return(0); 622 } 623 624 /* 625 * try to get rid of all non-directory type nodes 626 */ 627 if (unlink(name) < 0) { 628 syswarn(1, errno, "Could not unlink %s", name); 629 return(-1); 630 } 631 return(0); 632} 633 634/* 635 * chk_path() 636 * We were trying to create some kind of node in the file system and it 637 * failed. chk_path() makes sure the path up to the node exists and is 638 * writeable. When we have to create a directory that is missing along the 639 * path somewhere, the directory we create will be set to the same 640 * uid/gid as the file has (when uid and gid are being preserved). 641 * NOTE: this routine is a real performance loss. It is only used as a 642 * last resort when trying to create entries in the file system. 643 * Return: 644 * -1 when it could find nothing it is allowed to fix. 645 * 0 otherwise 646 */ 647 648int 649chk_path(char *name, uid_t st_uid, gid_t st_gid, char ** new_name) 650{ 651 char *spt = name; 652 int namelen = strlen(name); 653 struct stat sb; 654 int retval = -1; 655 656 /* 657 * watch out for paths with nodes stored directly in / (e.g. /bozo) 658 */ 659 if (*spt == '/') 660 ++spt; 661 662 for (;;) { 663 /* 664 * work forward from the first / and check each part of the path 665 */ 666 spt = strchr(spt, '/'); 667 if (spt == NULL) 668 break; 669 *spt = '\0'; 670 671 /* 672 * if it exists we assume it is a directory, it is not within 673 * the spec (at least it seems to read that way) to alter the 674 * file system for nodes NOT EXPLICITLY stored on the archive. 675 * If that assumption is changed, you would test the node here 676 * and figure out how to get rid of it (probably like some 677 * recursive unlink()) or fix up the directory permissions if 678 * required (do an access()). 679 */ 680 if (lstat(name, &sb) == 0) { 681 *(spt++) = '/'; 682 if (new_name==NULL) continue; 683 retval = 0; /* accept it one directory at a time */ 684 break; 685 } 686 687 /* 688 * the path fails at this point, see if we can create the 689 * needed directory and continue on 690 */ 691 if (mkdir(name, S_IRWXU | S_IRWXG | S_IRWXO) < 0) { 692 *spt = '/'; 693 retval = -1; 694 break; 695 } 696 697 /* 698 * we were able to create the directory. We will tell the 699 * caller that we found something to fix, and it is ok to try 700 * and create the node again. 701 */ 702 retval = 0; 703 if (pids) 704 (void)set_ids(name, st_uid, st_gid); 705 706 /* 707 * make sure the user doesn't have some strange umask that 708 * causes this newly created directory to be unusable. We fix 709 * the modes and restore them back to the creation default at 710 * the end of pax 711 */ 712 if ((access(name, R_OK | W_OK | X_OK) < 0) && 713 (lstat(name, &sb) == 0)) { 714 set_pmode(name, ((sb.st_mode & FILEBITS) | S_IRWXU)); 715 add_dir(name, namelen, &sb, 1); 716 } 717 *(spt++) = '/'; 718 if (new_name==NULL) continue; 719 break; 720 } 721 if ((new_name != NULL) && retval==0) { 722 /* save the new path */ 723 *(--spt) = '\0'; 724 /* 725 printf ("chdir to %s\n", name); 726 */ 727 if(0==chdir(name)) { 728 *spt++ = '/'; 729 /* 730 printf ("remaining path: %s\n",spt); 731 */ 732 *new_name = spt; 733 } else 734 *spt = '/'; 735 } 736 return(retval); 737} 738 739/* 740 * set_ftime() 741 * Set the access time and modification time for a named file. If frc 742 * is non-zero we force these times to be set even if the user did not 743 * request access and/or modification time preservation (this is also 744 * used by -t to reset access times). 745 * When frc is zero, only those times the user has asked for are set, the 746 * other ones are left alone. We do not assume the un-documented feature 747 * of many utimes() implementations that consider a 0 time value as a do 748 * not set request. 749 */ 750 751void 752set_ftime(char *fnm, time_t mtime, time_t atime, int frc) 753{ 754 static struct timeval tv[2] = {{0L, 0L}, {0L, 0L}}; 755 struct stat sb; 756 757 tv[0].tv_sec = (long)atime; 758 tv[1].tv_sec = (long)mtime; 759 if (!frc && (!patime || !pmtime)) { 760 /* 761 * if we are not forcing, only set those times the user wants 762 * set. We get the current values of the times if we need them. 763 */ 764 if (lstat(fnm, &sb) == 0) { 765 if (!patime) 766 tv[0].tv_sec = (long)sb.st_atime; 767 if (!pmtime) 768 tv[1].tv_sec = (long)sb.st_mtime; 769 } else 770 syswarn(0,errno,"Unable to obtain file stats %s", fnm); 771 } 772 773 /* 774 * set the times 775 */ 776 if (pax_invalid_action_write_cwd) { 777 char cwd_buff[MAXPATHLEN]; 778 char * cwd; 779 cwd = getcwd(&cwd_buff[0],MAXPATHLEN); 780 chdir(pax_invalid_action_write_cwd); 781 if (utimes(pax_invalid_action_write_path, tv) < 0) 782 syswarn(1, errno, "Access/modification time set failed on: %s", 783 pax_invalid_action_write_path); 784 chdir(cwd); 785 cleanup_pax_invalid_action(); 786 } else { 787 if (utimes(fnm, tv) < 0) 788 syswarn(1, errno, "Access/modification time set failed on: %s", 789 fnm); 790 } 791 return; 792} 793 794void 795fset_ftime(char *fnm, int fd, time_t mtime, time_t atime, int frc) 796{ 797 static struct timeval tv[2] = {{0L, 0L}, {0L, 0L}}; 798 struct stat sb; 799 800 tv[0].tv_sec = (long)atime; 801 tv[1].tv_sec = (long)mtime; 802 if (!frc && (!patime || !pmtime)) { 803 /* 804 * if we are not forcing, only set those times the user wants 805 * set. We get the current values of the times if we need them. 806 */ 807 if (fstat(fd, &sb) == 0) { 808 if (!patime) 809 tv[0].tv_sec = (long)sb.st_atime; 810 if (!pmtime) 811 tv[1].tv_sec = (long)sb.st_mtime; 812 } else 813 syswarn(0,errno,"Unable to obtain file stats %s", fnm); 814 } 815 /* 816 * set the times 817 */ 818 if (futimes(fd, tv) < 0) 819 syswarn(1, errno, "Access/modification time set failed on: %s", 820 fnm); 821 return; 822} 823 824/* 825 * set_ids() 826 * set the uid and gid of a file system node 827 * Return: 828 * 0 when set, -1 on failure 829 */ 830 831int 832set_ids(char *fnm, uid_t uid, gid_t gid) 833{ 834 if (chown(fnm, uid, gid) < 0) { 835 /* 836 * ignore EPERM unless in verbose mode or being run by root. 837 * if running as pax, POSIX requires a warning. 838 */ 839 if (strcmp(NM_PAX, argv0) == 0 || errno != EPERM || vflag || 840 geteuid() == 0) 841 syswarn(1, errno, "Unable to set file uid/gid of %s", 842 fnm); 843 return(-1); 844 } 845 return(0); 846} 847 848int 849fset_ids(char *fnm, int fd, uid_t uid, gid_t gid) 850{ 851 if (fchown(fd, uid, gid) < 0) { 852 /* 853 * ignore EPERM unless in verbose mode or being run by root. 854 * if running as pax, POSIX requires a warning. 855 */ 856 if (strcmp(NM_PAX, argv0) == 0 || errno != EPERM || vflag || 857 geteuid() == 0) 858 syswarn(1, errno, "Unable to set file uid/gid of %s", 859 fnm); 860 return(-1); 861 } 862 return(0); 863} 864 865#if !defined(__APPLE__) 866/* 867 * set_lids() 868 * set the uid and gid of a file system node 869 * Return: 870 * 0 when set, -1 on failure 871 */ 872 873int 874set_lids(char *fnm, uid_t uid, gid_t gid) 875{ 876 if (lchown(fnm, uid, gid) < 0) { 877 /* 878 * ignore EPERM unless in verbose mode or being run by root. 879 * if running as pax, POSIX requires a warning. 880 */ 881 if (strcmp(NM_PAX, argv0) == 0 || errno != EPERM || vflag || 882 geteuid() == 0) 883 syswarn(1, errno, "Unable to set file uid/gid of %s", 884 fnm); 885 return(-1); 886 } 887 return(0); 888} 889#endif /* !__APPLE__ */ 890 891/* 892 * set_pmode() 893 * Set file access mode 894 */ 895 896void 897set_pmode(char *fnm, mode_t mode) 898{ 899 mode &= ABITS; 900 if (chmod(fnm, mode) < 0) 901 syswarn(1, errno, "Could not set permissions on %s", fnm); 902 return; 903} 904 905void 906fset_pmode(char *fnm, int fd, mode_t mode) 907{ 908 mode &= ABITS; 909 if (fchmod(fd, mode) < 0) 910 syswarn(1, errno, "Could not set permissions on %s", fnm); 911 return; 912} 913 914/* 915 * file_write() 916 * Write/copy a file (during copy or archive extract). This routine knows 917 * how to copy files with lseek holes in it. (Which are read as file 918 * blocks containing all 0's but do not have any file blocks associated 919 * with the data). Typical examples of these are files created by dbm 920 * variants (.pag files). While the file size of these files are huge, the 921 * actual storage is quite small (the files are sparse). The problem is 922 * the holes read as all zeros so are probably stored on the archive that 923 * way (there is no way to determine if the file block is really a hole, 924 * we only know that a file block of all zero's can be a hole). 925 * At this writing, no major archive format knows how to archive files 926 * with holes. However, on extraction (or during copy, -rw) we have to 927 * deal with these files. Without detecting the holes, the files can 928 * consume a lot of file space if just written to disk. This replacement 929 * for write when passed the basic allocation size of a file system block, 930 * uses lseek whenever it detects the input data is all 0 within that 931 * file block. In more detail, the strategy is as follows: 932 * While the input is all zero keep doing an lseek. Keep track of when we 933 * pass over file block boundaries. Only write when we hit a non zero 934 * input. once we have written a file block, we continue to write it to 935 * the end (we stop looking at the input). When we reach the start of the 936 * next file block, start checking for zero blocks again. Working on file 937 * block boundaries significantly reduces the overhead when copying files 938 * that are NOT very sparse. This overhead (when compared to a write) is 939 * almost below the measurement resolution on many systems. Without it, 940 * files with holes cannot be safely copied. It does has a side effect as 941 * it can put holes into files that did not have them before, but that is 942 * not a problem since the file contents are unchanged (in fact it saves 943 * file space). (Except on paging files for diskless clients. But since we 944 * cannot determine one of those file from here, we ignore them). If this 945 * ever ends up on a system where CTG files are supported and the holes 946 * are not desired, just do a conditional test in those routines that 947 * call file_write() and have it call write() instead. BEFORE CLOSING THE 948 * FILE, make sure to call file_flush() when the last write finishes with 949 * an empty block. A lot of file systems will not create an lseek hole at 950 * the end. In this case we drop a single 0 at the end to force the 951 * trailing 0's in the file. 952 * ---Parameters--- 953 * rem: how many bytes left in this file system block 954 * isempt: have we written to the file block yet (is it empty) 955 * sz: basic file block allocation size 956 * cnt: number of bytes on this write 957 * str: buffer to write 958 * Return: 959 * number of bytes written, -1 on write (or lseek) error. 960 */ 961 962int 963file_write(int fd, char *str, int cnt, int *rem, int *isempt, int sz, 964 char *name) 965{ 966 char *pt; 967 char *end; 968 int wcnt; 969 char *st = str; 970 char **strp; 971 972 /* 973 * while we have data to process 974 */ 975 while (cnt) { 976 if (!*rem) { 977 /* 978 * We are now at the start of file system block again 979 * (or what we think one is...). start looking for 980 * empty blocks again 981 */ 982 *isempt = 1; 983 *rem = sz; 984 } 985 986 /* 987 * only examine up to the end of the current file block or 988 * remaining characters to write, whatever is smaller 989 */ 990 wcnt = MIN(cnt, *rem); 991 cnt -= wcnt; 992 *rem -= wcnt; 993 if (*isempt) { 994 /* 995 * have not written to this block yet, so we keep 996 * looking for zero's 997 */ 998 pt = st; 999 end = st + wcnt; 1000 1001 /* 1002 * look for a zero filled buffer 1003 */ 1004 while ((pt < end) && (*pt == '\0')) 1005 ++pt; 1006 1007 if (pt == end) { 1008 /* 1009 * skip, buf is empty so far 1010 */ 1011 if (fd > -1 && 1012 lseek(fd, (off_t)wcnt, SEEK_CUR) < 0) { 1013 syswarn(1,errno,"File seek on %s", 1014 name); 1015 return(-1); 1016 } 1017 st = pt; 1018 continue; 1019 } 1020 /* 1021 * drat, the buf is not zero filled 1022 */ 1023 *isempt = 0; 1024 } 1025 1026 /* 1027 * have non-zero data in this file system block, have to write 1028 */ 1029 switch (fd) { 1030 case -1: 1031 strp = &gnu_name_string; 1032 break; 1033 case -2: 1034 strp = &gnu_link_string; 1035 break; 1036 default: 1037 strp = NULL; 1038 break; 1039 } 1040 if (strp) { 1041 if (*strp) 1042 err(1, "WARNING! Major Internal Error! GNU hack Failing!"); 1043 *strp = malloc(wcnt + 1); 1044 if (*strp == NULL) { 1045 paxwarn(1, "Out of memory"); 1046 return(-1); 1047 } 1048 memcpy(*strp, st, wcnt); 1049 (*strp)[wcnt] = '\0'; 1050 break; 1051 } else if (write(fd, st, wcnt) != wcnt) { 1052 syswarn(1, errno, "Failed write to file %s", name); 1053 return(-1); 1054 } 1055 st += wcnt; 1056 } 1057 return(st - str); 1058} 1059 1060/* 1061 * file_flush() 1062 * when the last file block in a file is zero, many file systems will not 1063 * let us create a hole at the end. To get the last block with zeros, we 1064 * write the last BYTE with a zero (back up one byte and write a zero). 1065 */ 1066 1067void 1068file_flush(int fd, char *fname, int isempt) 1069{ 1070 static char blnk[] = "\0"; 1071 1072 /* 1073 * silly test, but make sure we are only called when the last block is 1074 * filled with all zeros. 1075 */ 1076 if (!isempt) 1077 return; 1078 1079 /* 1080 * move back one byte and write a zero 1081 */ 1082 if (lseek(fd, (off_t)-1, SEEK_CUR) < 0) { 1083 syswarn(1, errno, "Failed seek on file %s", fname); 1084 return; 1085 } 1086 1087 if (write(fd, blnk, 1) < 0) 1088 syswarn(1, errno, "Failed write to file %s", fname); 1089 return; 1090} 1091 1092/* 1093 * rdfile_close() 1094 * close a file we have beed reading (to copy or archive). If we have to 1095 * reset access time (tflag) do so (the times are stored in arcn). 1096 */ 1097 1098void 1099rdfile_close(ARCHD *arcn, int *fd) 1100{ 1101 /* 1102 * make sure the file is open 1103 */ 1104 if (*fd < 0) 1105 return; 1106 1107 (void)close(*fd); 1108 *fd = -1; 1109 if (!tflag) 1110 return; 1111 1112 /* 1113 * user wants last access time reset 1114 */ 1115 set_ftime(arcn->org_name, arcn->sb.st_mtime, arcn->sb.st_atime, 1); 1116 return; 1117} 1118 1119/* 1120 * set_crc() 1121 * read a file to calculate its crc. This is a real drag. Archive formats 1122 * that have this, end up reading the file twice (we have to write the 1123 * header WITH the crc before writing the file contents. Oh well... 1124 * Return: 1125 * 0 if was able to calculate the crc, -1 otherwise 1126 */ 1127 1128int 1129set_crc(ARCHD *arcn, int fd) 1130{ 1131 int i; 1132 int res; 1133 off_t cpcnt = 0L; 1134 u_long size; 1135 u_int32_t crc = 0; 1136 char tbuf[FILEBLK]; 1137 struct stat sb; 1138 1139 if (fd < 0) { 1140 /* 1141 * hmm, no fd, should never happen. well no crc then. 1142 */ 1143 arcn->crc = 0L; 1144 return(0); 1145 } 1146 1147 if ((size = (u_long)arcn->sb.st_blksize) > (u_long)sizeof(tbuf)) 1148 size = (u_long)sizeof(tbuf); 1149 1150 /* 1151 * read all the bytes we think that there are in the file. If the user 1152 * is trying to archive an active file, forget this file. 1153 */ 1154 for (;;) { 1155 if ((res = read(fd, tbuf, size)) <= 0) 1156 break; 1157 cpcnt += res; 1158 for (i = 0; i < res; ++i) 1159 crc += (tbuf[i] & 0xff); 1160 } 1161 1162 /* 1163 * safety check. we want to avoid archiving files that are active as 1164 * they can create inconsistent archive copies. 1165 */ 1166 if (cpcnt != arcn->sb.st_size) 1167 paxwarn(1, "File changed size %s", arcn->org_name); 1168 else if (fstat(fd, &sb) < 0) 1169 syswarn(1, errno, "Failed stat on %s", arcn->org_name); 1170 else if (arcn->sb.st_mtime != sb.st_mtime) 1171 paxwarn(1, "File %s was modified during read", arcn->org_name); 1172 else if (lseek(fd, (off_t)0L, SEEK_SET) < 0) 1173 syswarn(1, errno, "File rewind failed on: %s", arcn->org_name); 1174 else { 1175 arcn->crc = crc; 1176 return(0); 1177 } 1178 return(-1); 1179} 1180