1 /*- 2 * Copyright (c) 2007-2014, Juniper Networks, Inc. 3 * 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 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 __FBSDID("$FreeBSD$"); 29 30 #include "stand.h" 31 32 #include <sys/stat.h> 33 #include <sys/stdint.h> 34 #include <string.h> 35 #include <zlib.h> 36 37 #ifdef PKGFS_DEBUG 38 #define DBG(x) printf x 39 #else 40 #define DBG(x) 41 #endif 42 43 static int pkg_open(const char *, struct open_file *); 44 static int pkg_close(struct open_file *); 45 static int pkg_read(struct open_file *, void *, size_t, size_t *); 46 static off_t pkg_seek(struct open_file *, off_t, int); 47 static int pkg_stat(struct open_file *, struct stat *); 48 static int pkg_readdir(struct open_file *, struct dirent *); 49 static off_t pkg_atol(const char *, unsigned); 50 51 struct fs_ops pkgfs_fsops = { 52 "pkg", 53 pkg_open, 54 pkg_close, 55 pkg_read, 56 null_write, 57 pkg_seek, 58 pkg_stat, 59 pkg_readdir 60 }; 61 62 #define PKG_BUFSIZE 512 63 #define PKG_MAXCACHESZ (512 * 1024) 64 65 #define PKG_FILEEXT ".tgz" 66 67 /* 68 * Layout of POSIX 'ustar' header. 69 */ 70 struct ustar_hdr { 71 char ut_name[100]; 72 char ut_mode[8]; 73 char ut_uid[8]; 74 char ut_gid[8]; 75 char ut_size[12]; 76 char ut_mtime[12]; 77 char ut_checksum[8]; 78 char ut_typeflag[1]; 79 char ut_linkname[100]; 80 char ut_magic[6]; /* For POSIX: "ustar\0" */ 81 char ut_version[2]; /* For POSIX: "00" */ 82 char ut_uname[32]; 83 char ut_gname[32]; 84 char ut_rdevmajor[8]; 85 char ut_rdevminor[8]; 86 union { 87 struct { 88 char prefix[155]; 89 } posix; 90 struct { 91 char atime[12]; 92 char ctime[12]; 93 char offset[12]; 94 char longnames[4]; 95 char unused[1]; 96 struct gnu_sparse { 97 char offset[12]; 98 char numbytes[12]; 99 } sparse[4]; 100 char isextended[1]; 101 char realsize[12]; 102 } gnu; 103 } u; 104 u_char __padding[12]; 105 }; 106 107 struct package; 108 109 struct tarfile 110 { 111 struct package *tf_pkg; 112 struct tarfile *tf_next; 113 struct ustar_hdr tf_hdr; 114 off_t tf_ofs; 115 off_t tf_size; 116 off_t tf_fp; 117 size_t tf_cachesz; 118 void *tf_cache; 119 }; 120 121 struct package 122 { 123 struct package *pkg_chain; 124 int pkg_fd; 125 off_t pkg_ofs; 126 z_stream pkg_zs; 127 struct tarfile *pkg_first; 128 struct tarfile *pkg_last; 129 u_char pkg_buf[PKG_BUFSIZE]; 130 }; 131 132 static struct package *package = NULL; 133 134 static int new_package(int, struct package **); 135 static int cache_data(struct tarfile *tf, int); 136 137 void 138 pkgfs_cleanup(void) 139 { 140 struct package *chain; 141 struct tarfile *tf, *tfn; 142 143 while (package != NULL) { 144 inflateEnd(&package->pkg_zs); 145 close(package->pkg_fd); 146 147 tf = package->pkg_first; 148 while (tf != NULL) { 149 tfn = tf->tf_next; 150 if (tf->tf_cachesz > 0) 151 free(tf->tf_cache); 152 free(tf); 153 tf = tfn; 154 } 155 156 chain = package->pkg_chain; 157 free(package); 158 package = chain; 159 } 160 } 161 162 int 163 pkgfs_init(const char *pkgname, struct fs_ops *proto) 164 { 165 struct package *pkg; 166 int error, fd; 167 168 pkg = NULL; 169 if (proto != &pkgfs_fsops) 170 pkgfs_cleanup(); 171 172 exclusive_file_system = proto; 173 174 fd = open(pkgname, O_RDONLY); 175 176 exclusive_file_system = NULL; 177 178 if (fd == -1) 179 return (errno); 180 181 error = new_package(fd, &pkg); 182 if (error) { 183 close(fd); 184 return (error); 185 } 186 187 if (pkg == NULL) 188 return (EDOOFUS); 189 190 pkg->pkg_chain = package; 191 package = pkg; 192 exclusive_file_system = &pkgfs_fsops; 193 return (0); 194 } 195 196 static int get_mode(struct tarfile *); 197 static int get_zipped(struct package *, void *, size_t); 198 static int new_package(int, struct package **); 199 static struct tarfile *scan_tarfile(struct package *, struct tarfile *); 200 201 static int 202 pkg_open_follow(const char *fn, struct open_file *f, int lnks) 203 { 204 struct tarfile *tf; 205 206 if (fn == NULL || f == NULL) 207 return (EINVAL); 208 209 if (package == NULL) 210 return (ENXIO); 211 212 /* 213 * We can only read from a package, so reject request to open 214 * for write-only or read-write. 215 */ 216 if (f->f_flags != F_READ) 217 return (EPERM); 218 219 /* 220 * Scan the file headers for the named file. We stop scanning 221 * at the first filename that has the .pkg extension. This is 222 * a package within a package. We assume we have all the files 223 * we need up-front and without having to dig within nested 224 * packages. 225 * 226 * Note that we preserve streaming properties as much as possible. 227 */ 228 while (*fn == '/') 229 fn++; 230 231 /* 232 * Allow opening of the root directory for use by readdir() 233 * to support listing files in the package. 234 */ 235 if (*fn == '\0') { 236 f->f_fsdata = NULL; 237 return (0); 238 } 239 240 tf = scan_tarfile(package, NULL); 241 while (tf != NULL) { 242 if (strcmp(fn, tf->tf_hdr.ut_name) == 0) { 243 f->f_fsdata = tf; 244 tf->tf_fp = 0; /* Reset the file pointer. */ 245 DBG(("%s: found %s type %c\n", __func__, 246 fn, tf->tf_hdr.ut_typeflag[0])); 247 if (tf->tf_hdr.ut_typeflag[0] == '2') { 248 /* we have a symlink 249 * Note: ut_linkname is only 100 chars! 250 */ 251 if (lnks++ >= 8) 252 return (EMLINK); 253 return pkg_open_follow(tf->tf_hdr.ut_linkname, 254 f, lnks); 255 } 256 return (0); 257 } 258 tf = scan_tarfile(package, tf); 259 } 260 return (errno); 261 } 262 263 static int 264 pkg_open(const char *fn, struct open_file *f) 265 { 266 return pkg_open_follow(fn, f, 0); 267 } 268 269 static int 270 pkg_close(struct open_file *f) 271 { 272 struct tarfile *tf; 273 274 tf = (struct tarfile *)f->f_fsdata; 275 if (tf == NULL) 276 return (0); 277 278 /* 279 * Free up the cache if we read all of the file. 280 */ 281 if (tf->tf_fp == tf->tf_size && tf->tf_cachesz > 0) { 282 free(tf->tf_cache); 283 tf->tf_cachesz = 0; 284 } 285 return (0); 286 } 287 288 static int 289 pkg_read(struct open_file *f, void *buf, size_t size, size_t *res) 290 { 291 struct tarfile *tf; 292 char *p; 293 off_t fp; 294 size_t sz; 295 296 tf = (struct tarfile *)f->f_fsdata; 297 if (tf == NULL) { 298 if (res != NULL) 299 *res = size; 300 return (EBADF); 301 } 302 303 if (tf->tf_cachesz == 0) 304 cache_data(tf, 1); 305 306 fp = tf->tf_fp; 307 p = buf; 308 sz = 0; 309 while (size > 0) { 310 sz = tf->tf_size - fp; 311 if (fp < tf->tf_cachesz && tf->tf_cachesz < tf->tf_size) 312 sz = tf->tf_cachesz - fp; 313 if (size < sz) 314 sz = size; 315 if (sz == 0) 316 break; 317 318 if (fp < tf->tf_cachesz) { 319 /* Satisfy the request from cache. */ 320 memcpy(p, tf->tf_cache + fp, sz); 321 fp += sz; 322 p += sz; 323 size -= sz; 324 continue; 325 } 326 327 if (get_zipped(tf->tf_pkg, p, sz) == -1) { 328 sz = -1; 329 break; 330 } 331 332 fp += sz; 333 p += sz; 334 size -= sz; 335 } 336 337 tf->tf_fp = fp; 338 if (res != NULL) 339 *res = size; 340 return ((sz == -1) ? errno : 0); 341 } 342 343 static off_t 344 pkg_seek(struct open_file *f, off_t ofs, int whence) 345 { 346 char buf[512]; 347 struct tarfile *tf; 348 off_t delta; 349 off_t nofs; 350 size_t sz, res; 351 int error; 352 353 tf = (struct tarfile *)f->f_fsdata; 354 if (tf == NULL) { 355 errno = EBADF; 356 return (-1); 357 } 358 359 switch (whence) { 360 case SEEK_SET: 361 delta = ofs - tf->tf_fp; 362 break; 363 case SEEK_CUR: 364 delta = ofs; 365 break; 366 case SEEK_END: 367 delta = tf->tf_size - tf->tf_fp + ofs; 368 break; 369 default: 370 errno = EINVAL; 371 return (-1); 372 } 373 374 if (delta < 0) { 375 /* seeking backwards - ok if within cache */ 376 if (tf->tf_cachesz > 0 && tf->tf_fp <= tf->tf_cachesz) { 377 nofs = tf->tf_fp + delta; 378 if (nofs >= 0) { 379 tf->tf_fp = nofs; 380 return (tf->tf_fp); 381 } 382 } 383 DBG(("%s: negative file seek (%jd)\n", __func__, 384 (intmax_t)delta)); 385 errno = ESPIPE; 386 return (-1); 387 } 388 389 while (delta > 0 && tf->tf_fp < tf->tf_size) { 390 sz = (delta > sizeof(buf)) ? sizeof(buf) : delta; 391 error = pkg_read(f, buf, sz, &res); 392 if (error != 0) { 393 errno = error; 394 return (-1); 395 } 396 delta -= sz - res; 397 } 398 399 return (tf->tf_fp); 400 } 401 402 static int 403 pkg_stat(struct open_file *f, struct stat *sb) 404 { 405 struct tarfile *tf; 406 407 tf = (struct tarfile *)f->f_fsdata; 408 if (tf == NULL) 409 return (EBADF); 410 memset(sb, 0, sizeof(*sb)); 411 sb->st_mode = get_mode(tf); 412 if ((sb->st_mode & S_IFMT) == 0) { 413 /* tar file bug - assume regular file */ 414 sb->st_mode |= S_IFREG; 415 } 416 sb->st_size = tf->tf_size; 417 sb->st_blocks = (tf->tf_size + 511) / 512; 418 sb->st_mtime = pkg_atol(tf->tf_hdr.ut_mtime, 12); 419 sb->st_dev = (off_t)((uintptr_t)tf->tf_pkg); 420 sb->st_ino = tf->tf_ofs; /* unique per tf_pkg */ 421 return (0); 422 } 423 424 static int 425 pkg_readdir(struct open_file *f, struct dirent *d) 426 { 427 struct tarfile *tf; 428 429 tf = (struct tarfile *)f->f_fsdata; 430 if (tf != NULL) 431 return (EBADF); 432 433 tf = scan_tarfile(package, NULL); 434 if (tf == NULL) 435 return (ENOENT); 436 437 d->d_fileno = 0; 438 d->d_reclen = sizeof(*d); 439 d->d_type = DT_REG; 440 memcpy(d->d_name, tf->tf_hdr.ut_name, sizeof(d->d_name)); 441 return (0); 442 } 443 444 /* 445 * Low-level support functions. 446 */ 447 448 static int 449 get_byte(struct package *pkg, off_t *op) 450 { 451 int c; 452 453 if (pkg->pkg_zs.avail_in == 0) { 454 c = read(pkg->pkg_fd, pkg->pkg_buf, PKG_BUFSIZE); 455 if (c <= 0) 456 return (-1); 457 pkg->pkg_zs.avail_in = c; 458 pkg->pkg_zs.next_in = pkg->pkg_buf; 459 } 460 461 c = *pkg->pkg_zs.next_in; 462 pkg->pkg_zs.next_in++; 463 pkg->pkg_zs.avail_in--; 464 (*op)++; 465 return (c); 466 } 467 468 static int 469 get_zipped(struct package *pkg, void *buf, size_t bufsz) 470 { 471 int c; 472 473 pkg->pkg_zs.next_out = buf; 474 pkg->pkg_zs.avail_out = bufsz; 475 476 while (pkg->pkg_zs.avail_out) { 477 if (pkg->pkg_zs.avail_in == 0) { 478 c = read(pkg->pkg_fd, pkg->pkg_buf, PKG_BUFSIZE); 479 if (c <= 0) { 480 errno = EIO; 481 return (-1); 482 } 483 pkg->pkg_zs.avail_in = c; 484 pkg->pkg_zs.next_in = pkg->pkg_buf; 485 } 486 487 c = inflate(&pkg->pkg_zs, Z_SYNC_FLUSH); 488 if (c != Z_OK && c != Z_STREAM_END) { 489 errno = EIO; 490 return (-1); 491 } 492 } 493 494 pkg->pkg_ofs += bufsz; 495 return (0); 496 } 497 498 /** 499 * @brief 500 * cache data of a tarfile 501 * 502 * @param[in] tf 503 * tarfile pointer 504 * 505 * @param[in] force 506 * If file size > PKG_MAXCACHESZ, cache that much 507 * 508 * @return 0, -1 (errno set to error value) 509 */ 510 static int 511 cache_data(struct tarfile *tf, int force) 512 { 513 struct package *pkg; 514 size_t sz; 515 516 if (tf == NULL) { 517 DBG(("%s: no file to cache data for?\n", __func__)); 518 errno = EINVAL; 519 return (-1); 520 } 521 522 pkg = tf->tf_pkg; 523 if (pkg == NULL) { 524 DBG(("%s: no package associated with file?\n", __func__)); 525 errno = EINVAL; 526 return (-1); 527 } 528 529 if (tf->tf_cachesz > 0) { 530 DBG(("%s: data already cached\n", __func__)); 531 errno = EINVAL; 532 return (-1); 533 } 534 535 if (tf->tf_ofs != pkg->pkg_ofs) { 536 DBG(("%s: caching after force read of file %s?\n", 537 __func__, tf->tf_hdr.ut_name)); 538 errno = EINVAL; 539 return (-1); 540 } 541 542 /* We don't cache everything... */ 543 if (tf->tf_size > PKG_MAXCACHESZ && !force) { 544 errno = ENOBUFS; 545 return (-1); 546 } 547 548 sz = tf->tf_size < PKG_MAXCACHESZ ? tf->tf_size : PKG_MAXCACHESZ; 549 /* All files are padded to a multiple of 512 bytes. */ 550 sz = (sz + 0x1ff) & ~0x1ff; 551 552 tf->tf_cache = malloc(sz); 553 if (tf->tf_cache == NULL) { 554 DBG(("%s: could not allocate %d bytes\n", __func__, (int)sz)); 555 errno = ENOMEM; 556 return (-1); 557 } 558 559 tf->tf_cachesz = sz; 560 return (get_zipped(pkg, tf->tf_cache, sz)); 561 } 562 563 /* 564 * Note that this implementation does not (and should not!) obey 565 * locale settings; you cannot simply substitute strtol here, since 566 * it does obey locale. 567 */ 568 static off_t 569 pkg_atol8(const char *p, unsigned char_cnt) 570 { 571 int64_t l, limit, last_digit_limit; 572 int digit, sign, base; 573 574 base = 8; 575 limit = INT64_MAX / base; 576 last_digit_limit = INT64_MAX % base; 577 578 while (*p == ' ' || *p == '\t') 579 p++; 580 if (*p == '-') { 581 sign = -1; 582 p++; 583 } else 584 sign = 1; 585 586 l = 0; 587 digit = *p - '0'; 588 while (digit >= 0 && digit < base && char_cnt-- > 0) { 589 if (l>limit || (l == limit && digit > last_digit_limit)) { 590 l = UINT64_MAX; /* Truncate on overflow. */ 591 break; 592 } 593 l = (l * base) + digit; 594 digit = *++p - '0'; 595 } 596 return (sign < 0) ? -l : l; 597 } 598 599 /* 600 * Parse a base-256 integer. This is just a straight signed binary 601 * value in big-endian order, except that the high-order bit is 602 * ignored. Remember that "int64_t" may or may not be exactly 64 603 * bits; the implementation here tries to avoid making any assumptions 604 * about the actual size of an int64_t. It does assume we're using 605 * twos-complement arithmetic, though. 606 */ 607 static int64_t 608 pkg_atol256(const char *_p, unsigned char_cnt) 609 { 610 int64_t l, upper_limit, lower_limit; 611 const unsigned char *p = (const unsigned char *)_p; 612 613 upper_limit = INT64_MAX / 256; 614 lower_limit = INT64_MIN / 256; 615 616 /* Pad with 1 or 0 bits, depending on sign. */ 617 if ((0x40 & *p) == 0x40) 618 l = (int64_t)-1; 619 else 620 l = 0; 621 l = (l << 6) | (0x3f & *p++); 622 while (--char_cnt > 0) { 623 if (l > upper_limit) { 624 l = INT64_MAX; /* Truncate on overflow */ 625 break; 626 } else if (l < lower_limit) { 627 l = INT64_MIN; 628 break; 629 } 630 l = (l << 8) | (0xff & (int64_t)*p++); 631 } 632 return (l); 633 } 634 635 static off_t 636 pkg_atol(const char *p, unsigned char_cnt) 637 { 638 /* 639 * Technically, GNU pkg considers a field to be in base-256 640 * only if the first byte is 0xff or 0x80. 641 */ 642 if (*p & 0x80) 643 return (pkg_atol256(p, char_cnt)); 644 return (pkg_atol8(p, char_cnt)); 645 } 646 647 static int 648 get_mode(struct tarfile *tf) 649 { 650 return (pkg_atol(tf->tf_hdr.ut_mode, sizeof(tf->tf_hdr.ut_mode))); 651 } 652 653 /* GZip flag byte */ 654 #define ASCII_FLAG 0x01 /* bit 0 set: file probably ascii text */ 655 #define HEAD_CRC 0x02 /* bit 1 set: header CRC present */ 656 #define EXTRA_FIELD 0x04 /* bit 2 set: extra field present */ 657 #define ORIG_NAME 0x08 /* bit 3 set: original file name present */ 658 #define COMMENT 0x10 /* bit 4 set: file comment present */ 659 #define RESERVED 0xE0 /* bits 5..7: reserved */ 660 661 static int 662 new_package(int fd, struct package **pp) 663 { 664 struct package *pkg; 665 off_t ofs; 666 int flags, i, error; 667 668 pkg = malloc(sizeof(*pkg)); 669 if (pkg == NULL) 670 return (ENOMEM); 671 672 bzero(pkg, sizeof(*pkg)); 673 pkg->pkg_fd = fd; 674 675 /* 676 * Parse the header. 677 */ 678 error = EFTYPE; 679 ofs = 0; 680 681 /* Check megic. */ 682 if (get_byte(pkg, &ofs) != 0x1f || get_byte(pkg, &ofs) != 0x8b) 683 goto fail; 684 /* Check method. */ 685 if (get_byte(pkg, &ofs) != Z_DEFLATED) 686 goto fail; 687 /* Check flags. */ 688 flags = get_byte(pkg, &ofs); 689 if (flags & RESERVED) 690 goto fail; 691 692 /* Skip time, xflags and OS code. */ 693 for (i = 0; i < 6; i++) { 694 if (get_byte(pkg, &ofs) == -1) 695 goto fail; 696 } 697 698 /* Skip extra field. */ 699 if (flags & EXTRA_FIELD) { 700 i = (get_byte(pkg, &ofs) & 0xff) | 701 ((get_byte(pkg, &ofs) << 8) & 0xff); 702 while (i-- > 0) { 703 if (get_byte(pkg, &ofs) == -1) 704 goto fail; 705 } 706 } 707 708 /* Skip original file name. */ 709 if (flags & ORIG_NAME) { 710 do { 711 i = get_byte(pkg, &ofs); 712 } while (i != 0 && i != -1); 713 if (i == -1) 714 goto fail; 715 } 716 717 /* Print the comment if it's there. */ 718 if (flags & COMMENT) { 719 while (1) { 720 i = get_byte(pkg, &ofs); 721 if (i == -1) 722 goto fail; 723 if (i == 0) 724 break; 725 putchar(i); 726 } 727 } 728 729 /* Skip the CRC. */ 730 if (flags & HEAD_CRC) { 731 if (get_byte(pkg, &ofs) == -1) 732 goto fail; 733 if (get_byte(pkg, &ofs) == -1) 734 goto fail; 735 } 736 737 /* 738 * Done parsing the ZIP header. Spkgt the inflation engine. 739 */ 740 error = inflateInit2(&pkg->pkg_zs, -15); 741 if (error != Z_OK) 742 goto fail; 743 744 *pp = pkg; 745 return (0); 746 747 fail: 748 free(pkg); 749 return (error); 750 } 751 752 static struct tarfile * 753 scan_tarfile(struct package *pkg, struct tarfile *last) 754 { 755 char buf[512]; 756 struct tarfile *cur; 757 off_t ofs; 758 size_t sz; 759 760 cur = (last != NULL) ? last->tf_next : pkg->pkg_first; 761 if (cur == NULL) { 762 ofs = (last != NULL) ? last->tf_ofs + last->tf_size : 763 pkg->pkg_ofs; 764 ofs = (ofs + 0x1ff) & ~0x1ff; 765 766 /* Check if we've reached EOF. */ 767 if (ofs < pkg->pkg_ofs) { 768 errno = ENOSPC; 769 return (NULL); 770 } 771 772 if (ofs != pkg->pkg_ofs) { 773 if (last != NULL && pkg->pkg_ofs == last->tf_ofs) { 774 if (cache_data(last, 0) == -1) 775 return (NULL); 776 } else { 777 sz = ofs - pkg->pkg_ofs; 778 while (sz != 0) { 779 if (sz > sizeof(buf)) 780 sz = sizeof(buf); 781 if (get_zipped(pkg, buf, sz) == -1) 782 return (NULL); 783 sz = ofs - pkg->pkg_ofs; 784 } 785 } 786 } 787 788 cur = malloc(sizeof(*cur)); 789 if (cur == NULL) 790 return (NULL); 791 memset(cur, 0, sizeof(*cur)); 792 cur->tf_pkg = pkg; 793 794 while (1) { 795 if (get_zipped(pkg, &cur->tf_hdr, 796 sizeof(cur->tf_hdr)) == -1) { 797 free(cur); 798 return (NULL); 799 } 800 801 /* 802 * There are always 2 empty blocks appended to 803 * a PKG. It marks the end of the archive. 804 */ 805 if (strncmp(cur->tf_hdr.ut_magic, "ustar", 5) != 0) { 806 free(cur); 807 errno = ENOSPC; 808 return (NULL); 809 } 810 811 cur->tf_ofs = pkg->pkg_ofs; 812 cur->tf_size = pkg_atol(cur->tf_hdr.ut_size, 813 sizeof(cur->tf_hdr.ut_size)); 814 815 if (cur->tf_hdr.ut_name[0] != '+') 816 break; 817 818 /* 819 * Skip package meta-files. 820 */ 821 ofs = cur->tf_ofs + cur->tf_size; 822 ofs = (ofs + 0x1ff) & ~0x1ff; 823 while (pkg->pkg_ofs < ofs) { 824 if (get_zipped(pkg, buf, sizeof(buf)) == -1) { 825 free(cur); 826 return (NULL); 827 } 828 } 829 } 830 831 if (last != NULL) 832 last->tf_next = cur; 833 else 834 pkg->pkg_first = cur; 835 pkg->pkg_last = cur; 836 } 837 838 return (cur); 839 } 840