archival/unzip.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Mini unzip implementation for busybox
   4  *
   5  * Copyright (C) 2004 by Ed Clark
   6  *
   7  * Loosely based on original busybox unzip applet by Laurence Anderson.
   8  * All options and features should work in this version.
   9  *
  10  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  11  */
  12 /* For reference see
  13  * http://www.pkware.com/company/standards/appnote/
  14  * http://www.info-zip.org/pub/infozip/doc/appnote-iz-latest.zip
  15  *
  16  * TODO
  17  * Zip64 + other methods
  18  */
  19
  20 //config:config UNZIP
  21 //config:       bool "unzip"
  22 //config:       default y
  23 //config:       help
  24 //config:         unzip will list or extract files from a ZIP archive,
  25 //config:         commonly found on DOS/WIN systems. The default behavior
  26 //config:         (with no options) is to extract the archive into the
  27 //config:         current directory. Use the `-d' option to extract to a
  28 //config:         directory of your choice.
  29
  30 //applet:IF_UNZIP(APPLET(unzip, BB_DIR_USR_BIN, BB_SUID_DROP))
  31 //kbuild:lib-$(CONFIG_UNZIP) += unzip.o
  32
  33 //usage:#define unzip_trivial_usage
  34 //usage:       "[-lnopq] FILE[.zip] [FILE]... [-x FILE...] [-d DIR]"
  35 //usage:#define unzip_full_usage "\n\n"
  36 //usage:       "Extract FILEs from ZIP archive\n"
  37 //usage:     "\n        -l      List contents (with -q for short form)"
  38 //usage:     "\n        -n      Never overwrite files (default: ask)"
  39 //usage:     "\n        -o      Overwrite"
  40 //usage:     "\n        -p      Print to stdout"
  41 //usage:     "\n        -q      Quiet"
  42 //usage:     "\n        -x FILE Exclude FILEs"
  43 //usage:     "\n        -d DIR  Extract into DIR"
  44
  45 #include "libbb.h"
  46 #include "bb_archive.h"
  47
  48 #if 0
  49 # define dbg(...) bb_error_msg(__VA_ARGS__)
  50 #else
  51 # define dbg(...) ((void)0)
  52 #endif
  53
  54 enum {
  55 #if BB_BIG_ENDIAN
  56         ZIP_FILEHEADER_MAGIC = 0x504b0304,
  57         ZIP_CDF_MAGIC        = 0x504b0102, /* central directory's file header */
  58         ZIP_CDE_MAGIC        = 0x504b0506, /* "end of central directory" record */
  59         ZIP_DD_MAGIC         = 0x504b0708,
  60 #else
  61         ZIP_FILEHEADER_MAGIC = 0x04034b50,
  62         ZIP_CDF_MAGIC        = 0x02014b50,
  63         ZIP_CDE_MAGIC        = 0x06054b50,
  64         ZIP_DD_MAGIC         = 0x08074b50,
  65 #endif
  66 };
  67
  68 #define ZIP_HEADER_LEN 26
  69
  70 typedef union {
  71         uint8_t raw[ZIP_HEADER_LEN];
  72         struct {
  73                 uint16_t version;               /* 0-1 */
  74                 uint16_t zip_flags;             /* 2-3 */
  75                 uint16_t method;                /* 4-5 */
  76                 uint16_t modtime;               /* 6-7 */
  77                 uint16_t moddate;               /* 8-9 */
  78                 uint32_t crc32 PACKED;          /* 10-13 */
  79                 uint32_t cmpsize PACKED;        /* 14-17 */
  80                 uint32_t ucmpsize PACKED;       /* 18-21 */
  81                 uint16_t filename_len;          /* 22-23 */
  82                 uint16_t extra_len;             /* 24-25 */
  83         } formatted PACKED;
  84 } zip_header_t; /* PACKED - gcc 4.2.1 doesn't like it (spews warning) */
  85
  86 /* Check the offset of the last element, not the length.  This leniency
  87  * allows for poor packing, whereby the overall struct may be too long,
  88  * even though the elements are all in the right place.
  89  */
  90 struct BUG_zip_header_must_be_26_bytes {
  91         char BUG_zip_header_must_be_26_bytes[
  92                 offsetof(zip_header_t, formatted.extra_len) + 2
  93                         == ZIP_HEADER_LEN ? 1 : -1];
  94 };
  95
  96 #define FIX_ENDIANNESS_ZIP(zip_header) do { \
  97         (zip_header).formatted.version      = SWAP_LE16((zip_header).formatted.version     ); \
  98         (zip_header).formatted.method       = SWAP_LE16((zip_header).formatted.method      ); \
  99         (zip_header).formatted.modtime      = SWAP_LE16((zip_header).formatted.modtime     ); \
 100         (zip_header).formatted.moddate      = SWAP_LE16((zip_header).formatted.moddate     ); \
 101         (zip_header).formatted.crc32        = SWAP_LE32((zip_header).formatted.crc32       ); \
 102         (zip_header).formatted.cmpsize      = SWAP_LE32((zip_header).formatted.cmpsize     ); \
 103         (zip_header).formatted.ucmpsize     = SWAP_LE32((zip_header).formatted.ucmpsize    ); \
 104         (zip_header).formatted.filename_len = SWAP_LE16((zip_header).formatted.filename_len); \
 105         (zip_header).formatted.extra_len    = SWAP_LE16((zip_header).formatted.extra_len   ); \
 106 } while (0)
 107
 108 #define CDF_HEADER_LEN 42
 109
 110 typedef union {
 111         uint8_t raw[CDF_HEADER_LEN];
 112         struct {
 113                 /* uint32_t signature; 50 4b 01 02 */
 114                 uint16_t version_made_by;       /* 0-1 */
 115                 uint16_t version_needed;        /* 2-3 */
 116                 uint16_t cdf_flags;             /* 4-5 */
 117                 uint16_t method;                /* 6-7 */
 118                 uint16_t mtime;                 /* 8-9 */
 119                 uint16_t mdate;                 /* 10-11 */
 120                 uint32_t crc32;                 /* 12-15 */
 121                 uint32_t cmpsize;               /* 16-19 */
 122                 uint32_t ucmpsize;              /* 20-23 */
 123                 uint16_t file_name_length;      /* 24-25 */
 124                 uint16_t extra_field_length;    /* 26-27 */
 125                 uint16_t file_comment_length;   /* 28-29 */
 126                 uint16_t disk_number_start;     /* 30-31 */
 127                 uint16_t internal_file_attributes; /* 32-33 */
 128                 uint32_t external_file_attributes PACKED; /* 34-37 */
 129                 uint32_t relative_offset_of_local_header PACKED; /* 38-41 */
 130         } formatted PACKED;
 131 } cdf_header_t;
 132
 133 struct BUG_cdf_header_must_be_42_bytes {
 134         char BUG_cdf_header_must_be_42_bytes[
 135                 offsetof(cdf_header_t, formatted.relative_offset_of_local_header) + 4
 136                         == CDF_HEADER_LEN ? 1 : -1];
 137 };
 138
 139 #define FIX_ENDIANNESS_CDF(cdf_header) do { \
 140         (cdf_header).formatted.crc32        = SWAP_LE32((cdf_header).formatted.crc32       ); \
 141         (cdf_header).formatted.cmpsize      = SWAP_LE32((cdf_header).formatted.cmpsize     ); \
 142         (cdf_header).formatted.ucmpsize     = SWAP_LE32((cdf_header).formatted.ucmpsize    ); \
 143         (cdf_header).formatted.file_name_length = SWAP_LE16((cdf_header).formatted.file_name_length); \
 144         (cdf_header).formatted.extra_field_length = SWAP_LE16((cdf_header).formatted.extra_field_length); \
 145         (cdf_header).formatted.file_comment_length = SWAP_LE16((cdf_header).formatted.file_comment_length); \
 146         IF_DESKTOP( \
 147         (cdf_header).formatted.version_made_by = SWAP_LE16((cdf_header).formatted.version_made_by); \
 148         (cdf_header).formatted.external_file_attributes = SWAP_LE32((cdf_header).formatted.external_file_attributes); \
 149         ) \
 150 } while (0)
 151
 152 #define CDE_HEADER_LEN 16
 153
 154 typedef union {
 155         uint8_t raw[CDE_HEADER_LEN];
 156         struct {
 157                 /* uint32_t signature; 50 4b 05 06 */
 158                 uint16_t this_disk_no;
 159                 uint16_t disk_with_cdf_no;
 160                 uint16_t cdf_entries_on_this_disk;
 161                 uint16_t cdf_entries_total;
 162                 uint32_t cdf_size;
 163                 uint32_t cdf_offset;
 164                 /* uint16_t file_comment_length; */
 165                 /* .ZIP file comment (variable size) */
 166         } formatted PACKED;
 167 } cde_header_t;
 168
 169 struct BUG_cde_header_must_be_16_bytes {
 170         char BUG_cde_header_must_be_16_bytes[
 171                 sizeof(cde_header_t) == CDE_HEADER_LEN ? 1 : -1];
 172 };
 173
 174 #define FIX_ENDIANNESS_CDE(cde_header) do { \
 175         (cde_header).formatted.cdf_offset = SWAP_LE32((cde_header).formatted.cdf_offset); \
 176 } while (0)
 177
 178 enum { zip_fd = 3 };
 179
 180
 181 #if ENABLE_DESKTOP
 182
 183 /* Seen in the wild:
 184  * Self-extracting PRO2K3XP_32.exe contains 19078464 byte zip archive,
 185  * where CDE was nearly 48 kbytes before EOF.
 186  * (Surprisingly, it also apparently has *another* CDE structure
 187  * closer to the end, with bogus cdf_offset).
 188  * To make extraction work, bumped PEEK_FROM_END from 16k to 64k.
 189  */
 190 #define PEEK_FROM_END (64*1024)
 191
 192 /* This value means that we failed to find CDF */
 193 #define BAD_CDF_OFFSET ((uint32_t)0xffffffff)
 194
 195 /* NB: does not preserve file position! */
 196 static uint32_t find_cdf_offset(void)
 197 {
 198         cde_header_t cde_header;
 199         unsigned char *p;
 200         off_t end;
 201         unsigned char *buf = xzalloc(PEEK_FROM_END);
 202         uint32_t found;
 203
 204         end = xlseek(zip_fd, 0, SEEK_END);
 205         end -= PEEK_FROM_END;
 206         if (end < 0)
 207                 end = 0;
 208         dbg("Looking for cdf_offset starting from 0x%"OFF_FMT"x", end);
 209         xlseek(zip_fd, end, SEEK_SET);
 210         full_read(zip_fd, buf, PEEK_FROM_END);
 211
 212         found = BAD_CDF_OFFSET;
 213         p = buf;
 214         while (p <= buf + PEEK_FROM_END - CDE_HEADER_LEN - 4) {
 215                 if (*p != 'P') {
 216                         p++;
 217                         continue;
 218                 }
 219                 if (*++p != 'K')
 220                         continue;
 221                 if (*++p != 5)
 222                         continue;
 223                 if (*++p != 6)
 224                         continue;
 225                 /* we found CDE! */
 226                 memcpy(cde_header.raw, p + 1, CDE_HEADER_LEN);
 227                 FIX_ENDIANNESS_CDE(cde_header);
 228                 /*
 229                  * I've seen .ZIP files with seemingly valid CDEs
 230                  * where cdf_offset points past EOF - ??
 231                  * This check ignores such CDEs:
 232                  */
 233                 if (cde_header.formatted.cdf_offset < end + (p - buf)) {
 234                         found = cde_header.formatted.cdf_offset;
 235                         dbg("Possible cdf_offset:0x%x at 0x%"OFF_FMT"x",
 236                                 (unsigned)found, end + (p-3 - buf));
 237                         dbg("  cdf_offset+cdf_size:0x%x",
 238                                 (unsigned)(found + SWAP_LE32(cde_header.formatted.cdf_size)));
 239                         /*
 240                          * We do not "break" here because only the last CDE is valid.
 241                          * I've seen a .zip archive which contained a .zip file,
 242                          * uncompressed, and taking the first CDE was using
 243                          * the CDE inside that file!
 244                          */
 245                 }
 246         }
 247         free(buf);
 248         dbg("Found cdf_offset:0x%x", (unsigned)found);
 249         return found;
 250 };
 251
 252 static uint32_t read_next_cdf(uint32_t cdf_offset, cdf_header_t *cdf_ptr)
 253 {
 254         off_t org;
 255
 256         org = xlseek(zip_fd, 0, SEEK_CUR);
 257
 258         if (!cdf_offset)
 259                 cdf_offset = find_cdf_offset();
 260
 261         if (cdf_offset != BAD_CDF_OFFSET) {
 262                 dbg("Reading CDF at 0x%x", (unsigned)cdf_offset);
 263                 xlseek(zip_fd, cdf_offset + 4, SEEK_SET);
 264                 xread(zip_fd, cdf_ptr->raw, CDF_HEADER_LEN);
 265                 FIX_ENDIANNESS_CDF(*cdf_ptr);
 266                 dbg("  file_name_length:%u extra_field_length:%u file_comment_length:%u",
 267                         (unsigned)cdf_ptr->formatted.file_name_length,
 268                         (unsigned)cdf_ptr->formatted.extra_field_length,
 269                         (unsigned)cdf_ptr->formatted.file_comment_length
 270                 );
 271                 cdf_offset += 4 + CDF_HEADER_LEN
 272                         + cdf_ptr->formatted.file_name_length
 273                         + cdf_ptr->formatted.extra_field_length
 274                         + cdf_ptr->formatted.file_comment_length;
 275         }
 276
 277         dbg("Returning file position to 0x%"OFF_FMT"x", org);
 278         xlseek(zip_fd, org, SEEK_SET);
 279         return cdf_offset;
 280 };
 281 #endif
 282
 283 static void unzip_skip(off_t skip)
 284 {
 285         if (skip != 0)
 286                 if (lseek(zip_fd, skip, SEEK_CUR) == (off_t)-1)
 287                         bb_copyfd_exact_size(zip_fd, -1, skip);
 288 }
 289
 290 static void unzip_create_leading_dirs(const char *fn)
 291 {
 292         /* Create all leading directories */
 293         char *name = xstrdup(fn);
 294         if (bb_make_directory(dirname(name), 0777, FILEUTILS_RECUR)) {
 295                 xfunc_die(); /* bb_make_directory is noisy */
 296         }
 297         free(name);
 298 }
 299
 300 static void unzip_extract(zip_header_t *zip_header, int dst_fd)
 301 {
 302         if (zip_header->formatted.method == 0) {
 303                 /* Method 0 - stored (not compressed) */
 304                 off_t size = zip_header->formatted.ucmpsize;
 305                 if (size)
 306                         bb_copyfd_exact_size(zip_fd, dst_fd, size);
 307         } else {
 308                 /* Method 8 - inflate */
 309                 transformer_state_t xstate;
 310                 init_transformer_state(&xstate);
 311                 xstate.bytes_in = zip_header->formatted.cmpsize;
 312                 xstate.src_fd = zip_fd;
 313                 xstate.dst_fd = dst_fd;
 314                 if (inflate_unzip(&xstate) < 0)
 315                         bb_error_msg_and_die("inflate error");
 316                 /* Validate decompression - crc */
 317                 if (zip_header->formatted.crc32 != (xstate.crc32 ^ 0xffffffffL)) {
 318                         bb_error_msg_and_die("crc error");
 319                 }
 320                 /* Validate decompression - size */
 321                 if (zip_header->formatted.ucmpsize != xstate.bytes_out) {
 322                         /* Don't die. Who knows, maybe len calculation
 323                          * was botched somewhere. After all, crc matched! */
 324                         bb_error_msg("bad length");
 325                 }
 326         }
 327 }
 328
 329 static void my_fgets80(char *buf80)
 330 {
 331         fflush_all();
 332         if (!fgets(buf80, 80, stdin)) {
 333                 bb_perror_msg_and_die("can't read standard input");
 334         }
 335 }
 336
 337 int unzip_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 338 int unzip_main(int argc, char **argv)
 339 {
 340         enum { O_PROMPT, O_NEVER, O_ALWAYS };
 341
 342         zip_header_t zip_header;
 343         smallint quiet = 0;
 344         IF_NOT_DESKTOP(const) smallint verbose = 0;
 345         smallint listing = 0;
 346         smallint overwrite = O_PROMPT;
 347         smallint x_opt_seen;
 348 #if ENABLE_DESKTOP
 349         uint32_t cdf_offset;
 350 #endif
 351         unsigned long total_usize;
 352         unsigned long total_size;
 353         unsigned total_entries;
 354         int dst_fd = -1;
 355         char *src_fn = NULL;
 356         char *dst_fn = NULL;
 357         llist_t *zaccept = NULL;
 358         llist_t *zreject = NULL;
 359         char *base_dir = NULL;
 360         int i, opt;
 361         char key_buf[80]; /* must match size used by my_fgets80 */
 362         struct stat stat_buf;
 363
 364 /* -q, -l and -v: UnZip 5.52 of 28 February 2005, by Info-ZIP:
 365  *
 366  * # /usr/bin/unzip -qq -v decompress_unlzma.i.zip
 367  *   204372  Defl:N    35278  83%  09-06-09 14:23  0d056252  decompress_unlzma.i
 368  * # /usr/bin/unzip -q -v decompress_unlzma.i.zip
 369  *  Length   Method    Size  Ratio   Date   Time   CRC-32    Name
 370  * --------  ------  ------- -----   ----   ----   ------    ----
 371  *   204372  Defl:N    35278  83%  09-06-09 14:23  0d056252  decompress_unlzma.i
 372  * --------          -------  ---                            -------
 373  *   204372            35278  83%                            1 file
 374  * # /usr/bin/unzip -v decompress_unlzma.i.zip
 375  * Archive:  decompress_unlzma.i.zip
 376  *  Length   Method    Size  Ratio   Date   Time   CRC-32    Name
 377  * --------  ------  ------- -----   ----   ----   ------    ----
 378  *   204372  Defl:N    35278  83%  09-06-09 14:23  0d056252  decompress_unlzma.i
 379  * --------          -------  ---                            -------
 380  *   204372            35278  83%                            1 file
 381  * # unzip -v decompress_unlzma.i.zip
 382  * Archive:  decompress_unlzma.i.zip
 383  *   Length     Date   Time    Name
 384  *  --------    ----   ----    ----
 385  *    204372  09-06-09 14:23   decompress_unlzma.i
 386  *  --------                   -------
 387  *    204372                   1 files
 388  * # /usr/bin/unzip -l -qq decompress_unlzma.i.zip
 389  *    204372  09-06-09 14:23   decompress_unlzma.i
 390  * # /usr/bin/unzip -l -q decompress_unlzma.i.zip
 391  *   Length     Date   Time    Name
 392  *  --------    ----   ----    ----
 393  *    204372  09-06-09 14:23   decompress_unlzma.i
 394  *  --------                   -------
 395  *    204372                   1 file
 396  * # /usr/bin/unzip -l decompress_unlzma.i.zip
 397  * Archive:  decompress_unlzma.i.zip
 398  *   Length     Date   Time    Name
 399  *  --------    ----   ----    ----
 400  *    204372  09-06-09 14:23   decompress_unlzma.i
 401  *  --------                   -------
 402  *    204372                   1 file
 403  */
 404
 405         x_opt_seen = 0;
 406         /* '-' makes getopt return 1 for non-options */
 407         while ((opt = getopt(argc, argv, "-d:lnopqxv")) != -1) {
 408                 switch (opt) {
 409                 case 'd':  /* Extract to base directory */
 410                         base_dir = optarg;
 411                         break;
 412
 413                 case 'l': /* List */
 414                         listing = 1;
 415                         break;
 416
 417                 case 'n': /* Never overwrite existing files */
 418                         overwrite = O_NEVER;
 419                         break;
 420
 421                 case 'o': /* Always overwrite existing files */
 422                         overwrite = O_ALWAYS;
 423                         break;
 424
 425                 case 'p': /* Extract files to stdout and fall through to set verbosity */
 426                         dst_fd = STDOUT_FILENO;
 427
 428                 case 'q': /* Be quiet */
 429                         quiet++;
 430                         break;
 431
 432                 case 'v': /* Verbose list */
 433                         IF_DESKTOP(verbose++;)
 434                         listing = 1;
 435                         break;
 436
 437                 case 'x':
 438                         x_opt_seen = 1;
 439                         break;
 440
 441                 case 1:
 442                         if (!src_fn) {
 443                                 /* The zip file */
 444                                 /* +5: space for ".zip" and NUL */
 445                                 src_fn = xmalloc(strlen(optarg) + 5);
 446                                 strcpy(src_fn, optarg);
 447                         } else if (!x_opt_seen) {
 448                                 /* Include files */
 449                                 llist_add_to(&zaccept, optarg);
 450                         } else {
 451                                 /* Exclude files */
 452                                 llist_add_to(&zreject, optarg);
 453                         }
 454                         break;
 455
 456                 default:
 457                         bb_show_usage();
 458                 }
 459         }
 460
 461 #ifndef __GLIBC__
 462         /*
 463          * This code is needed for non-GNU getopt
 464          * which doesn't understand "-" in option string.
 465          * The -x option won't work properly in this case:
 466          * "unzip a.zip q -x w e" will be interpreted as
 467          * "unzip a.zip q w e -x" = "unzip a.zip q w e"
 468          */
 469         argv += optind;
 470         if (argv[0]) {
 471                 /* +5: space for ".zip" and NUL */
 472                 src_fn = xmalloc(strlen(argv[0]) + 5);
 473                 strcpy(src_fn, argv[0]);
 474                 while (*++argv)
 475                         llist_add_to(&zaccept, *argv);
 476         }
 477 #endif
 478
 479         if (!src_fn) {
 480                 bb_show_usage();
 481         }
 482
 483         /* Open input file */
 484         if (LONE_DASH(src_fn)) {
 485                 xdup2(STDIN_FILENO, zip_fd);
 486                 /* Cannot use prompt mode since zip data is arriving on STDIN */
 487                 if (overwrite == O_PROMPT)
 488                         overwrite = O_NEVER;
 489         } else {
 490                 static const char extn[][5] = { ".zip", ".ZIP" };
 491                 char *ext = src_fn + strlen(src_fn);
 492                 int src_fd;
 493
 494                 i = 0;
 495                 for (;;) {
 496                         src_fd = open(src_fn, O_RDONLY);
 497                         if (src_fd >= 0)
 498                                 break;
 499                         if (++i > 2) {
 500                                 *ext = '\0';
 501                                 bb_error_msg_and_die("can't open %s[.zip]", src_fn);
 502                         }
 503                         strcpy(ext, extn[i - 1]);
 504                 }
 505                 xmove_fd(src_fd, zip_fd);
 506         }
 507
 508         /* Change dir if necessary */
 509         if (base_dir)
 510                 xchdir(base_dir);
 511
 512         if (quiet <= 1) { /* not -qq */
 513                 if (quiet == 0)
 514                         printf("Archive:  %s\n", src_fn);
 515                 if (listing) {
 516                         puts(verbose ?
 517                                 " Length   Method    Size  Cmpr    Date    Time   CRC-32   Name\n"
 518                                 "--------  ------  ------- ---- ---------- ----- --------  ----"
 519                                 :
 520                                 "  Length      Date    Time    Name\n"
 521                                 "---------  ---------- -----   ----"
 522                                 );
 523                 }
 524         }
 525
 526 /* Example of an archive with one 0-byte long file named 'z'
 527  * created by Zip 2.31 on Unix:
 528  * 0000 [50 4b]03 04 0a 00 00 00 00 00 42 1a b8 3c 00 00 |PK........B..<..|
 529  *       sig........ vneed flags compr mtime mdate crc32>
 530  * 0010  00 00 00 00 00 00 00 00 00 00 01 00 15 00 7a 55 |..............zU|
 531  *      >..... csize...... usize...... fnlen exlen fn ex>
 532  * 0020  54 09 00 03 cc d3 f9 4b cc d3 f9 4b 55 78 04 00 |T......K...KUx..|
 533  *      >tra_field......................................
 534  * 0030  00 00 00 00[50 4b]01 02 17 03 0a 00 00 00 00 00 |....PK..........|
 535  *       ........... sig........ vmade vneed flags compr
 536  * 0040  42 1a b8 3c 00 00 00 00 00 00 00 00 00 00 00 00 |B..<............|
 537  *       mtime mdate crc32...... csize...... usize......
 538  * 0050  01 00 0d 00 00 00 00 00 00 00 00 00 a4 81 00 00 |................|
 539  *       fnlen exlen clen. dnum. iattr eattr...... relofs> (eattr = rw-r--r--)
 540  * 0060  00 00 7a 55 54 05 00 03 cc d3 f9 4b 55 78 00 00 |..zUT......KUx..|
 541  *      >..... fn extra_field...........................
 542  * 0070 [50 4b]05 06 00 00 00 00 01 00 01 00 3c 00 00 00 |PK..........<...|
 543  * 0080  34 00 00 00 00 00                               |4.....|
 544  */
 545         total_usize = 0;
 546         total_size = 0;
 547         total_entries = 0;
 548 #if ENABLE_DESKTOP
 549         cdf_offset = 0;
 550 #endif
 551         while (1) {
 552                 uint32_t magic;
 553                 mode_t dir_mode = 0777;
 554 #if ENABLE_DESKTOP
 555                 mode_t file_mode = 0666;
 556 #endif
 557
 558                 /* Check magic number */
 559                 xread(zip_fd, &magic, 4);
 560                 /* Central directory? It's at the end, so exit */
 561                 if (magic == ZIP_CDF_MAGIC) {
 562                         dbg("got ZIP_CDF_MAGIC");
 563                         break;
 564                 }
 565 #if ENABLE_DESKTOP
 566                 /* Data descriptor? It was a streaming file, go on */
 567                 if (magic == ZIP_DD_MAGIC) {
 568                         dbg("got ZIP_DD_MAGIC");
 569                         /* skip over duplicate crc32, cmpsize and ucmpsize */
 570                         unzip_skip(3 * 4);
 571                         continue;
 572                 }
 573 #endif
 574                 if (magic != ZIP_FILEHEADER_MAGIC)
 575                         bb_error_msg_and_die("invalid zip magic %08X", (int)magic);
 576                 dbg("got ZIP_FILEHEADER_MAGIC");
 577
 578                 /* Read the file header */
 579                 xread(zip_fd, zip_header.raw, ZIP_HEADER_LEN);
 580                 FIX_ENDIANNESS_ZIP(zip_header);
 581                 if ((zip_header.formatted.method != 0) && (zip_header.formatted.method != 8)) {
 582                         bb_error_msg_and_die("unsupported method %d", zip_header.formatted.method);
 583                 }
 584 #if !ENABLE_DESKTOP
 585                 if (zip_header.formatted.zip_flags & SWAP_LE16(0x0009)) {
 586                         bb_error_msg_and_die("zip flags 1 and 8 are not supported");
 587                 }
 588 #else
 589                 if (zip_header.formatted.zip_flags & SWAP_LE16(0x0001)) {
 590                         /* 0x0001 - encrypted */
 591                         bb_error_msg_and_die("zip flag 1 (encryption) is not supported");
 592                 }
 593
 594                 if (cdf_offset != BAD_CDF_OFFSET) {
 595                         cdf_header_t cdf_header;
 596                         cdf_offset = read_next_cdf(cdf_offset, &cdf_header);
 597                         /*
 598                          * Note: cdf_offset can become BAD_CDF_OFFSET after the above call.
 599                          */
 600                         if (zip_header.formatted.zip_flags & SWAP_LE16(0x0008)) {
 601                                 /* 0x0008 - streaming. [u]cmpsize can be reliably gotten
 602                                  * only from Central Directory. See unzip_doc.txt
 603                                  */
 604                                 zip_header.formatted.crc32    = cdf_header.formatted.crc32;
 605                                 zip_header.formatted.cmpsize  = cdf_header.formatted.cmpsize;
 606                                 zip_header.formatted.ucmpsize = cdf_header.formatted.ucmpsize;
 607                         }
 608                         if ((cdf_header.formatted.version_made_by >> 8) == 3) {
 609                                 /* This archive is created on Unix */
 610                                 dir_mode = file_mode = (cdf_header.formatted.external_file_attributes >> 16);
 611                         }
 612                 }
 613                 if (cdf_offset == BAD_CDF_OFFSET
 614                  && (zip_header.formatted.zip_flags & SWAP_LE16(0x0008))
 615                 ) {
 616                         /* If it's a streaming zip, we _require_ CDF */
 617                         bb_error_msg_and_die("can't find file table");
 618                 }
 619 #endif
 620                 dbg("File cmpsize:0x%x extra_len:0x%x ucmpsize:0x%x",
 621                         (unsigned)zip_header.formatted.cmpsize,
 622                         (unsigned)zip_header.formatted.extra_len,
 623                         (unsigned)zip_header.formatted.ucmpsize
 624                 );
 625
 626                 /* Read filename */
 627                 free(dst_fn);
 628                 dst_fn = xzalloc(zip_header.formatted.filename_len + 1);
 629                 xread(zip_fd, dst_fn, zip_header.formatted.filename_len);
 630
 631                 /* Skip extra header bytes */
 632                 unzip_skip(zip_header.formatted.extra_len);
 633
 634                 /* Guard against "/abspath", "/../" and similar attacks */
 635                 overlapping_strcpy(dst_fn, strip_unsafe_prefix(dst_fn));
 636
 637                 /* Filter zip entries */
 638                 if (find_list_entry(zreject, dst_fn)
 639                  || (zaccept && !find_list_entry(zaccept, dst_fn))
 640                 ) { /* Skip entry */
 641                         i = 'n';
 642                 } else {
 643                         if (listing) {
 644                                 /* List entry */
 645                                 char dtbuf[sizeof("mm-dd-yyyy hh:mm")];
 646                                 sprintf(dtbuf, "%02u-%02u-%04u %02u:%02u",
 647                                         (zip_header.formatted.moddate >> 5) & 0xf,  // mm: 0x01e0
 648                                         (zip_header.formatted.moddate)      & 0x1f, // dd: 0x001f
 649                                         (zip_header.formatted.moddate >> 9) + 1980, // yy: 0xfe00
 650                                         (zip_header.formatted.modtime >> 11),       // hh: 0xf800
 651                                         (zip_header.formatted.modtime >> 5) & 0x3f  // mm: 0x07e0
 652                                         // seconds/2 are not shown, encoded in ----------- 0x001f
 653                                 );
 654                                 if (!verbose) {
 655                                         //      "  Length      Date    Time    Name\n"
 656                                         //      "---------  ---------- -----   ----"
 657                                         printf(       "%9u  " "%s   "         "%s\n",
 658                                                 (unsigned)zip_header.formatted.ucmpsize,
 659                                                 dtbuf,
 660                                                 dst_fn);
 661                                 } else {
 662                                         unsigned long percents = zip_header.formatted.ucmpsize - zip_header.formatted.cmpsize;
 663                                         if ((int32_t)percents < 0)
 664                                                 percents = 0; /* happens if ucmpsize < cmpsize */
 665                                         percents = percents * 100;
 666                                         if (zip_header.formatted.ucmpsize)
 667                                                 percents /= zip_header.formatted.ucmpsize;
 668                                         //      " Length   Method    Size  Cmpr    Date    Time   CRC-32   Name\n"
 669                                         //      "--------  ------  ------- ---- ---------- ----- --------  ----"
 670                                         printf(      "%8u  %s"        "%9u%4u%% " "%s "         "%08x  "  "%s\n",
 671                                                 (unsigned)zip_header.formatted.ucmpsize,
 672                                                 zip_header.formatted.method == 0 ? "Stored" : "Defl:N", /* Defl is method 8 */
 673 /* TODO: show other methods?
 674  *  1 - Shrunk
 675  *  2 - Reduced with compression factor 1
 676  *  3 - Reduced with compression factor 2
 677  *  4 - Reduced with compression factor 3
 678  *  5 - Reduced with compression factor 4
 679  *  6 - Imploded
 680  *  7 - Reserved for Tokenizing compression algorithm
 681  *  9 - Deflate64
 682  * 10 - PKWARE Data Compression Library Imploding
 683  * 11 - Reserved by PKWARE
 684  * 12 - BZIP2
 685  */
 686                                                 (unsigned)zip_header.formatted.cmpsize,
 687                                                 (unsigned)percents,
 688                                                 dtbuf,
 689                                                 zip_header.formatted.crc32,
 690                                                 dst_fn);
 691                                         total_size += zip_header.formatted.cmpsize;
 692                                 }
 693                                 total_usize += zip_header.formatted.ucmpsize;
 694                                 i = 'n';
 695                         } else if (dst_fd == STDOUT_FILENO) {
 696                                 /* Extracting to STDOUT */
 697                                 i = -1;
 698                         } else if (last_char_is(dst_fn, '/')) {
 699                                 /* Extract directory */
 700                                 if (stat(dst_fn, &stat_buf) == -1) {
 701                                         if (errno != ENOENT) {
 702                                                 bb_perror_msg_and_die("can't stat '%s'", dst_fn);
 703                                         }
 704                                         if (!quiet) {
 705                                                 printf("   creating: %s\n", dst_fn);
 706                                         }
 707                                         unzip_create_leading_dirs(dst_fn);
 708                                         if (bb_make_directory(dst_fn, dir_mode, FILEUTILS_IGNORE_CHMOD_ERR)) {
 709                                                 xfunc_die();
 710                                         }
 711                                 } else {
 712                                         if (!S_ISDIR(stat_buf.st_mode)) {
 713                                                 bb_error_msg_and_die("'%s' exists but is not a %s",
 714                                                         dst_fn, "directory");
 715                                         }
 716                                 }
 717                                 i = 'n';
 718                         } else {
 719                                 /* Extract file */
 720  check_file:
 721                                 if (stat(dst_fn, &stat_buf) == -1) {
 722                                         /* File does not exist */
 723                                         if (errno != ENOENT) {
 724                                                 bb_perror_msg_and_die("can't stat '%s'", dst_fn);
 725                                         }
 726                                         i = 'y';
 727                                 } else {
 728                                         /* File already exists */
 729                                         if (overwrite == O_NEVER) {
 730                                                 i = 'n';
 731                                         } else if (S_ISREG(stat_buf.st_mode)) {
 732                                                 /* File is regular file */
 733                                                 if (overwrite == O_ALWAYS) {
 734                                                         i = 'y';
 735                                                 } else {
 736                                                         printf("replace %s? [y]es, [n]o, [A]ll, [N]one, [r]ename: ", dst_fn);
 737                                                         my_fgets80(key_buf);
 738                                                         i = key_buf[0];
 739                                                 }
 740                                         } else {
 741                                                 /* File is not regular file */
 742                                                 bb_error_msg_and_die("'%s' exists but is not a %s",
 743                                                         dst_fn, "regular file");
 744                                         }
 745                                 }
 746                         }
 747                 }
 748
 749                 switch (i) {
 750                 case 'A':
 751                         overwrite = O_ALWAYS;
 752                 case 'y': /* Open file and fall into unzip */
 753                         unzip_create_leading_dirs(dst_fn);
 754 #if ENABLE_DESKTOP
 755                         dst_fd = xopen3(dst_fn, O_WRONLY | O_CREAT | O_TRUNC, file_mode);
 756 #else
 757                         dst_fd = xopen(dst_fn, O_WRONLY | O_CREAT | O_TRUNC);
 758 #endif
 759                 case -1: /* Unzip */
 760                         if (!quiet) {
 761                                 printf("  inflating: %s\n", dst_fn);
 762                         }
 763                         unzip_extract(&zip_header, dst_fd);
 764                         if (dst_fd != STDOUT_FILENO) {
 765                                 /* closing STDOUT is potentially bad for future business */
 766                                 close(dst_fd);
 767                         }
 768                         break;
 769
 770                 case 'N':
 771                         overwrite = O_NEVER;
 772                 case 'n':
 773                         /* Skip entry data */
 774                         unzip_skip(zip_header.formatted.cmpsize);
 775                         break;
 776
 777                 case 'r':
 778                         /* Prompt for new name */
 779                         printf("new name: ");
 780                         my_fgets80(key_buf);
 781                         free(dst_fn);
 782                         dst_fn = xstrdup(key_buf);
 783                         chomp(dst_fn);
 784                         goto check_file;
 785
 786                 default:
 787                         printf("error: invalid response [%c]\n", (char)i);
 788                         goto check_file;
 789                 }
 790
 791                 total_entries++;
 792         }
 793
 794         if (listing && quiet <= 1) {
 795                 if (!verbose) {
 796                         //      "  Length      Date    Time    Name\n"
 797                         //      "---------  ---------- -----   ----"
 798                         printf( " --------%21s"               "-------\n"
 799                                      "%9lu%21s"               "%u files\n",
 800                                 "",
 801                                 total_usize, "", total_entries);
 802                 } else {
 803                         unsigned long percents = total_usize - total_size;
 804                         if ((long)percents < 0)
 805                                 percents = 0; /* happens if usize < size */
 806                         percents = percents * 100;
 807                         if (total_usize)
 808                                 percents /= total_usize;
 809                         //      " Length   Method    Size  Cmpr    Date    Time   CRC-32   Name\n"
 810                         //      "--------  ------  ------- ---- ---------- ----- --------  ----"
 811                         printf( "--------          ------- ----%28s"                      "----\n"
 812                                 "%8lu"              "%17lu%4u%%%28s"                      "%u files\n",
 813                                 "",
 814                                 total_usize, total_size, (unsigned)percents, "",
 815                                 total_entries);
 816                 }
 817         }
 818
 819         return 0;
 820 }