1 /* vi: set sw=4 ts=4: */
3 * Mini unzip implementation for busybox
5 * Copyright (C) 2004 by Ed Clark
7 * Loosely based on original busybox unzip applet by Laurence Anderson.
8 * All options and features should work in this version.
10 * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
14 * http://www.pkware.com/company/standards/appnote/
15 * http://www.info-zip.org/pub/infozip/doc/appnote-iz-latest.zip
20 * Zip64 + other methods
21 * Improve handling of zip format, ie.
22 * - deferred CRC, comp. & uncomp. lengths (zip header flags bit 3)
23 * - unix file permissions, etc.
28 #include "unarchive.h"
32 ZIP_FILEHEADER_MAGIC = 0x504b0304,
33 ZIP_CDS_MAGIC = 0x504b0102,
34 ZIP_CDS_END_MAGIC = 0x504b0506,
35 ZIP_DD_MAGIC = 0x504b0708,
37 ZIP_FILEHEADER_MAGIC = 0x04034b50,
38 ZIP_CDS_MAGIC = 0x02014b50,
39 ZIP_CDS_END_MAGIC = 0x06054b50,
40 ZIP_DD_MAGIC = 0x08074b50,
44 #define ZIP_HEADER_LEN 26
47 uint8_t raw[ZIP_HEADER_LEN];
49 uint16_t version; /* 0-1 */
50 uint16_t flags; /* 2-3 */
51 uint16_t method; /* 4-5 */
52 uint16_t modtime; /* 6-7 */
53 uint16_t moddate; /* 8-9 */
54 uint32_t crc32 PACKED; /* 10-13 */
55 uint32_t cmpsize PACKED; /* 14-17 */
56 uint32_t ucmpsize PACKED; /* 18-21 */
57 uint16_t filename_len; /* 22-23 */
58 uint16_t extra_len; /* 24-25 */
60 } zip_header_t; /* PACKED - gcc 4.2.1 doesn't like it (spews warning) */
62 /* Check the offset of the last element, not the length. This leniency
63 * allows for poor packing, whereby the overall struct may be too long,
64 * even though the elements are all in the right place.
66 struct BUG_zip_header_must_be_26_bytes {
67 char BUG_zip_header_must_be_26_bytes[
68 offsetof(zip_header_t, formatted.extra_len) + 2 ==
69 ZIP_HEADER_LEN ? 1 : -1];
72 #define FIX_ENDIANNESS(zip_header) do { \
73 (zip_header).formatted.version = SWAP_LE16((zip_header).formatted.version ); \
74 (zip_header).formatted.flags = SWAP_LE16((zip_header).formatted.flags ); \
75 (zip_header).formatted.method = SWAP_LE16((zip_header).formatted.method ); \
76 (zip_header).formatted.modtime = SWAP_LE16((zip_header).formatted.modtime ); \
77 (zip_header).formatted.moddate = SWAP_LE16((zip_header).formatted.moddate ); \
78 (zip_header).formatted.crc32 = SWAP_LE32((zip_header).formatted.crc32 ); \
79 (zip_header).formatted.cmpsize = SWAP_LE32((zip_header).formatted.cmpsize ); \
80 (zip_header).formatted.ucmpsize = SWAP_LE32((zip_header).formatted.ucmpsize ); \
81 (zip_header).formatted.filename_len = SWAP_LE16((zip_header).formatted.filename_len); \
82 (zip_header).formatted.extra_len = SWAP_LE16((zip_header).formatted.extra_len ); \
85 static void unzip_skip(int fd, off_t skip)
87 bb_copyfd_exact_size(fd, -1, skip);
90 static void unzip_create_leading_dirs(const char *fn)
92 /* Create all leading directories */
93 char *name = xstrdup(fn);
94 if (bb_make_directory(dirname(name), 0777, FILEUTILS_RECUR)) {
95 bb_error_msg_and_die("exiting"); /* bb_make_directory is noisy */
100 static void unzip_extract(zip_header_t *zip_header, int src_fd, int dst_fd)
102 if (zip_header->formatted.flags & (0x0008|0x0001)) {
103 /* 0x0001 - encrypted */
104 /* 0x0008 - streaming. [u]cmpsize can be reliably gotten
105 * only from Central Directory. See unzip_doc.txt */
106 bb_error_msg_and_die("zip flags 8 and 1 are not supported");
108 if (zip_header->formatted.method == 0) {
109 /* Method 0 - stored (not compressed) */
110 off_t size = zip_header->formatted.ucmpsize;
112 bb_copyfd_exact_size(src_fd, dst_fd, size);
114 /* Method 8 - inflate */
115 inflate_unzip_result res;
116 if (inflate_unzip(&res, zip_header->formatted.cmpsize, src_fd, dst_fd) < 0)
117 bb_error_msg_and_die("inflate error");
118 /* Validate decompression - crc */
119 if (zip_header->formatted.crc32 != (res.crc ^ 0xffffffffL)) {
120 bb_error_msg_and_die("crc error");
122 /* Validate decompression - size */
123 if (zip_header->formatted.ucmpsize != res.bytes_out) {
124 /* Don't die. Who knows, maybe len calculation
125 * was botched somewhere. After all, crc matched! */
126 bb_error_msg("bad length");
131 int unzip_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
132 int unzip_main(int argc, char **argv)
134 enum { O_PROMPT, O_NEVER, O_ALWAYS };
136 zip_header_t zip_header;
137 smallint verbose = 1;
138 smallint listing = 0;
139 smallint overwrite = O_PROMPT;
141 unsigned total_entries;
146 llist_t *zaccept = NULL;
147 llist_t *zreject = NULL;
148 char *base_dir = NULL;
152 struct stat stat_buf;
154 /* '-' makes getopt return 1 for non-options */
155 while ((opt = getopt(argc, argv, "-d:lnopqx")) != -1) {
157 case 0: /* Options */
163 case 'n': /* Never overwrite existing files */
167 case 'o': /* Always overwrite existing files */
168 overwrite = O_ALWAYS;
171 case 'p': /* Extract files to stdout and fall through to set verbosity */
172 dst_fd = STDOUT_FILENO;
174 case 'q': /* Be quiet */
178 case 1: /* The zip file */
179 /* +5: space for ".zip" and NUL */
180 src_fn = xmalloc(strlen(optarg) + 5);
181 strcpy(src_fn, optarg);
191 case 1: /* Include files */
193 llist_add_to(&zaccept, optarg);
207 case 2 : /* Exclude files */
209 llist_add_to(&zreject, optarg);
212 if (opt == 'd') { /* Extract to base directory */
224 if (src_fn == NULL) {
228 /* Open input file */
229 if (LONE_DASH(src_fn)) {
230 src_fd = STDIN_FILENO;
231 /* Cannot use prompt mode since zip data is arriving on STDIN */
232 if (overwrite == O_PROMPT)
235 static const char extn[][5] = {"", ".zip", ".ZIP"};
236 int orig_src_fn_len = strlen(src_fn);
238 for (i = 0; (i < 3) && (src_fd == -1); i++) {
239 strcpy(src_fn + orig_src_fn_len, extn[i]);
240 src_fd = open(src_fn, O_RDONLY);
243 src_fn[orig_src_fn_len] = '\0';
244 bb_error_msg_and_die("can't open %s, %s.zip, %s.ZIP", src_fn, src_fn, src_fn);
248 /* Change dir if necessary */
253 printf("Archive: %s\n", src_fn);
255 puts(" Length Date Time Name\n"
256 " -------- ---- ---- ----");
265 /* Check magic number */
266 xread(src_fd, &magic, 4);
267 if (magic == ZIP_CDS_MAGIC)
269 if (magic != ZIP_FILEHEADER_MAGIC)
270 bb_error_msg_and_die("invalid zip magic %08X", magic);
272 /* Read the file header */
273 xread(src_fd, zip_header.raw, ZIP_HEADER_LEN);
274 FIX_ENDIANNESS(zip_header);
275 if ((zip_header.formatted.method != 0) && (zip_header.formatted.method != 8)) {
276 bb_error_msg_and_die("unsupported method %d", zip_header.formatted.method);
281 dst_fn = xzalloc(zip_header.formatted.filename_len + 1);
282 xread(src_fd, dst_fn, zip_header.formatted.filename_len);
284 /* Skip extra header bytes */
285 unzip_skip(src_fd, zip_header.formatted.extra_len);
287 /* Filter zip entries */
288 if (find_list_entry(zreject, dst_fn)
289 || (zaccept && !find_list_entry(zaccept, dst_fn))
293 } else { /* Extract entry */
294 if (listing) { /* List entry */
296 unsigned dostime = zip_header.formatted.modtime | (zip_header.formatted.moddate << 16);
297 printf("%9u %02u-%02u-%02u %02u:%02u %s\n",
298 zip_header.formatted.ucmpsize,
299 (dostime & 0x01e00000) >> 21,
300 (dostime & 0x001f0000) >> 16,
301 (((dostime & 0xfe000000) >> 25) + 1980) % 100,
302 (dostime & 0x0000f800) >> 11,
303 (dostime & 0x000007e0) >> 5,
305 total_size += zip_header.formatted.ucmpsize;
308 /* short listing -- filenames only */
312 } else if (dst_fd == STDOUT_FILENO) { /* Extracting to STDOUT */
314 } else if (last_char_is(dst_fn, '/')) { /* Extract directory */
315 if (stat(dst_fn, &stat_buf) == -1) {
316 if (errno != ENOENT) {
317 bb_perror_msg_and_die("cannot stat '%s'", dst_fn);
320 printf(" creating: %s\n", dst_fn);
322 unzip_create_leading_dirs(dst_fn);
323 if (bb_make_directory(dst_fn, 0777, 0)) {
324 bb_error_msg_and_die("exiting");
327 if (!S_ISDIR(stat_buf.st_mode)) {
328 bb_error_msg_and_die("'%s' exists but is not directory", dst_fn);
333 } else { /* Extract file */
335 if (stat(dst_fn, &stat_buf) == -1) { /* File does not exist */
336 if (errno != ENOENT) {
337 bb_perror_msg_and_die("cannot stat '%s'", dst_fn);
340 } else { /* File already exists */
341 if (overwrite == O_NEVER) {
343 } else if (S_ISREG(stat_buf.st_mode)) { /* File is regular file */
344 if (overwrite == O_ALWAYS) {
347 printf("replace %s? [y]es, [n]o, [A]ll, [N]one, [r]ename: ", dst_fn);
348 if (!fgets(key_buf, sizeof(key_buf), stdin)) {
349 bb_perror_msg_and_die("cannot read input");
353 } else { /* File is not regular file */
354 bb_error_msg_and_die("'%s' exists but is not regular file", dst_fn);
362 overwrite = O_ALWAYS;
363 case 'y': /* Open file and fall into unzip */
364 unzip_create_leading_dirs(dst_fn);
365 dst_fd = xopen(dst_fn, O_WRONLY | O_CREAT | O_TRUNC);
368 printf(" inflating: %s\n", dst_fn);
370 unzip_extract(&zip_header, src_fd, dst_fd);
371 if (dst_fd != STDOUT_FILENO) {
372 /* closing STDOUT is potentially bad for future business */
380 /* Skip entry data */
381 unzip_skip(src_fd, zip_header.formatted.cmpsize);
385 /* Prompt for new name */
386 printf("new name: ");
387 if (!fgets(key_buf, sizeof(key_buf), stdin)) {
388 bb_perror_msg_and_die("cannot read input");
391 dst_fn = xstrdup(key_buf);
396 printf("error: invalid response [%c]\n",(char)i);
400 /* Data descriptor section */
401 if (zip_header.formatted.flags & 4) {
402 /* skip over duplicate crc, compressed size and uncompressed size */
403 unzip_skip(src_fd, 12);
407 if (listing && verbose) {
408 printf(" -------- -------\n"
410 total_size, total_entries);