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 //config:config UNZIP
20 //config:	bool "unzip (26 kb)"
21 //config:	default y
22 //config:	help
23 //config:	unzip will list or extract files from a ZIP archive,
24 //config:	commonly found on DOS/WIN systems. The default behavior
25 //config:	(with no options) is to extract the archive into the
26 //config:	current directory.
27 //config:
28 //config:config FEATURE_UNZIP_CDF
29 //config:	bool "Read and use Central Directory data"
30 //config:	default y
31 //config:	depends on UNZIP
32 //config:	help
33 //config:	If you know that you only need to deal with simple
34 //config:	ZIP files without deleted/updated files, SFX archives etc,
35 //config:	you can reduce code size by unselecting this option.
36 //config:	To support less trivial ZIPs, say Y.
37 //config:
38 //config:config FEATURE_UNZIP_BZIP2
39 //config:	bool "Support compression method 12 (bzip2)"
40 //config:	default y
41 //config:	depends on FEATURE_UNZIP_CDF && DESKTOP
42 // FEATURE_UNZIP_CDF is needed, otherwise we can't find start of next file
43 // DESKTOP is needed to get back uncompressed length
44 //config:
45 //config:config FEATURE_UNZIP_LZMA
46 //config:	bool "Support compression method 14 (lzma)"
47 //config:	default y
48 //config:	depends on FEATURE_UNZIP_CDF && DESKTOP
49 //config:
50 //config:config FEATURE_UNZIP_XZ
51 //config:	bool "Support compression method 95 (xz)"
52 //config:	default y
53 //config:	depends on FEATURE_UNZIP_CDF && DESKTOP
54 
55 //applet:IF_UNZIP(APPLET(unzip, BB_DIR_USR_BIN, BB_SUID_DROP))
56 //kbuild:lib-$(CONFIG_UNZIP) += unzip.o
57 
58 //usage:#define unzip_trivial_usage
59 //usage:       "[-lnojpq] FILE[.zip] [FILE]... [-x FILE]... [-d DIR]"
60 //usage:#define unzip_full_usage "\n\n"
61 //usage:       "Extract FILEs from ZIP archive\n"
62 //usage:     "\n	-l	List contents (with -q for short form)"
63 //usage:     "\n	-n	Never overwrite files (default: ask)"
64 //usage:     "\n	-o	Overwrite"
65 //usage:     "\n	-j	Do not restore paths"
66 //usage:     "\n	-p	Write to stdout"
67 //usage:     "\n	-t	Test"
68 //usage:     "\n	-q	Quiet"
69 //usage:     "\n	-x FILE	Exclude FILEs"
70 //usage:     "\n	-d DIR	Extract into DIR"
71 
72 #include "libbb.h"
73 #include "bb_archive.h"
74 
75 #if 0
76 # define dbg(...) bb_error_msg(__VA_ARGS__)
77 #else
78 # define dbg(...) ((void)0)
79 #endif
80 
81 enum {
82 #if BB_BIG_ENDIAN
83 	ZIP_FILEHEADER_MAGIC = 0x504b0304,
84 	ZIP_CDF_MAGIC        = 0x504b0102, /* CDF item */
85 	ZIP_CDE_MAGIC        = 0x504b0506, /* End of CDF */
86 	ZIP64_CDE_MAGIC      = 0x504b0606, /* End of Zip64 CDF */
87 	ZIP_DD_MAGIC         = 0x504b0708,
88 #else
89 	ZIP_FILEHEADER_MAGIC = 0x04034b50,
90 	ZIP_CDF_MAGIC        = 0x02014b50,
91 	ZIP_CDE_MAGIC        = 0x06054b50,
92 	ZIP64_CDE_MAGIC      = 0x06064b50,
93 	ZIP_DD_MAGIC         = 0x08074b50,
94 #endif
95 };
96 
97 #define ZIP_HEADER_LEN 26
98 
99 typedef union {
100 	uint8_t raw[ZIP_HEADER_LEN];
101 	struct {
102 		uint16_t version;               /* 0-1 */
103 		uint16_t zip_flags;             /* 2-3 */
104 		uint16_t method;                /* 4-5 */
105 		uint16_t modtime;               /* 6-7 */
106 		uint16_t moddate;               /* 8-9 */
107 		uint32_t crc32 PACKED;          /* 10-13 */
108 		uint32_t cmpsize PACKED;        /* 14-17 */
109 		uint32_t ucmpsize PACKED;       /* 18-21 */
110 		uint16_t filename_len;          /* 22-23 */
111 		uint16_t extra_len;             /* 24-25 */
112 		/* filename follows (not NUL terminated) */
113 		/* extra field follows */
114 		/* data follows */
115 	} fmt PACKED;
116 } zip_header_t; /* PACKED - gcc 4.2.1 doesn't like it (spews warning) */
117 
118 #define FIX_ENDIANNESS_ZIP(zip) \
119 do { if (BB_BIG_ENDIAN) { \
120 	(zip).fmt.method        = SWAP_LE16((zip).fmt.method      ); \
121 	(zip).fmt.crc32         = SWAP_LE32((zip).fmt.crc32       ); \
122 	(zip).fmt.cmpsize       = SWAP_LE32((zip).fmt.cmpsize     ); \
123 	(zip).fmt.ucmpsize      = SWAP_LE32((zip).fmt.ucmpsize    ); \
124 	(zip).fmt.filename_len  = SWAP_LE16((zip).fmt.filename_len); \
125 	(zip).fmt.extra_len     = SWAP_LE16((zip).fmt.extra_len   ); \
126 }} while (0)
127 
128 #define CDF_HEADER_LEN 42
129 
130 typedef union {
131 	uint8_t raw[CDF_HEADER_LEN];
132 	struct {
133 		/* uint32_t signature; 50 4b 01 02 */
134 		uint16_t version_made_by;       /* 0-1 */
135 		uint16_t version_needed;        /* 2-3 */
136 		uint16_t cdf_flags;             /* 4-5 */
137 		uint16_t method;                /* 6-7 */
138 		uint16_t modtime;               /* 8-9 */
139 		uint16_t moddate;               /* 10-11 */
140 		uint32_t crc32;                 /* 12-15 */
141 		uint32_t cmpsize;               /* 16-19 */
142 		uint32_t ucmpsize;              /* 20-23 */
143 		uint16_t filename_len;          /* 24-25 */
144 		uint16_t extra_len;             /* 26-27 */
145 		uint16_t file_comment_length;   /* 28-29 */
146 		uint16_t disk_number_start;     /* 30-31 */
147 		uint16_t internal_attributes;   /* 32-33 */
148 		uint32_t external_attributes PACKED; /* 34-37 */
149 		uint32_t relative_offset_of_local_header PACKED; /* 38-41 */
150 		/* filename follows (not NUL terminated) */
151 		/* extra field follows */
152 		/* file comment follows */
153 	} fmt PACKED;
154 } cdf_header_t;
155 
156 #define FIX_ENDIANNESS_CDF(cdf) \
157 do { if (BB_BIG_ENDIAN) { \
158 	(cdf).fmt.version_made_by = SWAP_LE16((cdf).fmt.version_made_by); \
159 	(cdf).fmt.version_needed  = SWAP_LE16((cdf).fmt.version_needed ); \
160 	(cdf).fmt.method          = SWAP_LE16((cdf).fmt.method         ); \
161 	(cdf).fmt.modtime         = SWAP_LE16((cdf).fmt.modtime        ); \
162 	(cdf).fmt.moddate         = SWAP_LE16((cdf).fmt.moddate        ); \
163 	(cdf).fmt.crc32           = SWAP_LE32((cdf).fmt.crc32          ); \
164 	(cdf).fmt.cmpsize         = SWAP_LE32((cdf).fmt.cmpsize        ); \
165 	(cdf).fmt.ucmpsize        = SWAP_LE32((cdf).fmt.ucmpsize       ); \
166 	(cdf).fmt.filename_len    = SWAP_LE16((cdf).fmt.filename_len   ); \
167 	(cdf).fmt.extra_len       = SWAP_LE16((cdf).fmt.extra_len      ); \
168 	(cdf).fmt.file_comment_length = SWAP_LE16((cdf).fmt.file_comment_length); \
169 	(cdf).fmt.external_attributes = SWAP_LE32((cdf).fmt.external_attributes); \
170 }} while (0)
171 
172 #define CDE_LEN 16
173 
174 typedef union {
175 	uint8_t raw[CDE_LEN];
176 	struct {
177 		/* uint32_t signature; 50 4b 05 06 */
178 		uint16_t this_disk_no;
179 		uint16_t disk_with_cdf_no;
180 		uint16_t cdf_entries_on_this_disk;
181 		uint16_t cdf_entries_total;
182 		uint32_t cdf_size;
183 		uint32_t cdf_offset;
184 		/* uint16_t archive_comment_length; */
185 		/* archive comment follows */
186 	} fmt PACKED;
187 } cde_t;
188 
189 #define FIX_ENDIANNESS_CDE(cde) \
190 do { if (BB_BIG_ENDIAN) { \
191 	(cde).fmt.cdf_offset = SWAP_LE32((cde).fmt.cdf_offset); \
192 }} while (0)
193 
194 struct BUG {
195 	/* Check the offset of the last element, not the length.  This leniency
196 	 * allows for poor packing, whereby the overall struct may be too long,
197 	 * even though the elements are all in the right place.
198 	 */
199 	char BUG_zip_header_must_be_26_bytes[
200 		offsetof(zip_header_t, fmt.extra_len) + 2
201 			== ZIP_HEADER_LEN ? 1 : -1];
202 	char BUG_cdf_header_must_be_42_bytes[
203 		offsetof(cdf_header_t, fmt.relative_offset_of_local_header) + 4
204 			== CDF_HEADER_LEN ? 1 : -1];
205 	char BUG_cde_must_be_16_bytes[
206 		sizeof(cde_t) == CDE_LEN ? 1 : -1];
207 };
208 
209 
210 enum { zip_fd = 3 };
211 
212 
213 /* This value means that we failed to find CDF */
214 #define BAD_CDF_OFFSET ((uint32_t)0xffffffff)
215 
216 #if !ENABLE_FEATURE_UNZIP_CDF
217 
218 # define find_cdf_offset() BAD_CDF_OFFSET
219 
220 #else
221 /* Seen in the wild:
222  * Self-extracting PRO2K3XP_32.exe contains 19078464 byte zip archive,
223  * where CDE was nearly 48 kbytes before EOF.
224  * (Surprisingly, it also apparently has *another* CDE structure
225  * closer to the end, with bogus cdf_offset).
226  * To make extraction work, bumped PEEK_FROM_END from 16k to 64k.
227  */
228 #define PEEK_FROM_END (64*1024)
229 /* NB: does not preserve file position! */
find_cdf_offset(void)230 static uint32_t find_cdf_offset(void)
231 {
232 	cde_t cde;
233 	unsigned char *buf;
234 	unsigned char *p;
235 	off_t end;
236 	uint32_t found;
237 
238 	end = lseek(zip_fd, 0, SEEK_END);
239 	if (end == (off_t) -1)
240 		return BAD_CDF_OFFSET;
241 
242 	end -= PEEK_FROM_END;
243 	if (end < 0)
244 		end = 0;
245 
246 	dbg("Looking for cdf_offset starting from 0x%"OFF_FMT"x", end);
247 	xlseek(zip_fd, end, SEEK_SET);
248 	buf = xzalloc(PEEK_FROM_END);
249 	full_read(zip_fd, buf, PEEK_FROM_END);
250 
251 	found = BAD_CDF_OFFSET;
252 	p = buf;
253 	while (p <= buf + PEEK_FROM_END - CDE_LEN - 4) {
254 		if (*p != 'P') {
255 			p++;
256 			continue;
257 		}
258 		if (*++p != 'K')
259 			continue;
260 		if (*++p != 5)
261 			continue;
262 		if (*++p != 6)
263 			continue;
264 		/* we found CDE! */
265 		memcpy(cde.raw, p + 1, CDE_LEN);
266 		dbg("cde.this_disk_no:%d",             cde.fmt.this_disk_no            );
267 		dbg("cde.disk_with_cdf_no:%d",         cde.fmt.disk_with_cdf_no        );
268 		dbg("cde.cdf_entries_on_this_disk:%d", cde.fmt.cdf_entries_on_this_disk);
269 		dbg("cde.cdf_entries_total:%d",        cde.fmt.cdf_entries_total       );
270 		dbg("cde.cdf_size:%d",                 cde.fmt.cdf_size                );
271 		dbg("cde.cdf_offset:%x",               cde.fmt.cdf_offset              );
272 		FIX_ENDIANNESS_CDE(cde);
273 		/*
274 		 * I've seen .ZIP files with seemingly valid CDEs
275 		 * where cdf_offset points past EOF - ??
276 		 * This check ignores such CDEs:
277 		 */
278 		if (cde.fmt.cdf_offset < end + (p - buf)) {
279 			found = cde.fmt.cdf_offset;
280 			dbg("Possible cdf_offset:0x%x at 0x%"OFF_FMT"x",
281 				(unsigned)found, end + (p-3 - buf));
282 			dbg("  cdf_offset+cdf_size:0x%x",
283 				(unsigned)(found + SWAP_LE32(cde.fmt.cdf_size)));
284 			/*
285 			 * We do not "break" here because only the last CDE is valid.
286 			 * I've seen a .zip archive which contained a .zip file,
287 			 * uncompressed, and taking the first CDE was using
288 			 * the CDE inside that file!
289 			 */
290 		}
291 	}
292 	free(buf);
293 	dbg("Found cdf_offset:0x%x", (unsigned)found);
294 	return found;
295 };
296 
read_next_cdf(uint32_t cdf_offset,cdf_header_t * cdf)297 static uint32_t read_next_cdf(uint32_t cdf_offset, cdf_header_t *cdf)
298 {
299 	uint32_t magic;
300 
301 	if (cdf_offset == BAD_CDF_OFFSET)
302 		return cdf_offset;
303 
304 	dbg("Reading CDF at 0x%x", (unsigned)cdf_offset);
305 	xlseek(zip_fd, cdf_offset, SEEK_SET);
306 	xread(zip_fd, &magic, 4);
307 	/* Central Directory End? Assume CDF has ended.
308 	 * (more correct method is to use cde.cdf_entries_total counter)
309 	 */
310 	if (magic == ZIP_CDE_MAGIC) {
311 		dbg("got ZIP_CDE_MAGIC");
312 		return 0; /* EOF */
313 	}
314 	if (magic == ZIP64_CDE_MAGIC) { /* seen in .zip with >4GB files */
315 		dbg("got ZIP64_CDE_MAGIC");
316 		return 0; /* EOF */
317 	}
318 	xread(zip_fd, cdf->raw, CDF_HEADER_LEN);
319 
320 	FIX_ENDIANNESS_CDF(*cdf);
321 	dbg("  magic:%08x filename_len:%u extra_len:%u file_comment_length:%u",
322 		magic,
323 		(unsigned)cdf->fmt.filename_len,
324 		(unsigned)cdf->fmt.extra_len,
325 		(unsigned)cdf->fmt.file_comment_length
326 	);
327 //TODO: require that magic == ZIP_CDF_MAGIC?
328 
329 	cdf_offset += 4 + CDF_HEADER_LEN
330 		+ cdf->fmt.filename_len
331 		+ cdf->fmt.extra_len
332 		+ cdf->fmt.file_comment_length;
333 
334 	dbg("Next cdf_offset 0x%x", cdf_offset);
335 	return cdf_offset;
336 };
337 #endif
338 
die_if_bad_fnamesize(unsigned sz)339 static void die_if_bad_fnamesize(unsigned sz)
340 {
341 	if (sz > 0xfff) /* more than 4k?! no funny business please */
342 		bb_simple_error_msg_and_die("bad archive");
343 }
344 
unzip_skip(off_t skip)345 static void unzip_skip(off_t skip)
346 {
347 	if (skip != 0)
348 		if (lseek(zip_fd, skip, SEEK_CUR) == (off_t)-1)
349 			bb_copyfd_exact_size(zip_fd, -1, skip);
350 }
351 
unzip_create_leading_dirs(const char * fn)352 static void unzip_create_leading_dirs(const char *fn)
353 {
354 	/* Create all leading directories */
355 	char *name = xstrdup(fn);
356 
357 	/* mode of -1: set mode according to umask */
358 	if (bb_make_directory(dirname(name), -1, FILEUTILS_RECUR)) {
359 		xfunc_die(); /* bb_make_directory is noisy */
360 	}
361 	free(name);
362 }
363 
364 #if ENABLE_FEATURE_UNZIP_CDF
unzip_extract_symlink(llist_t ** symlink_placeholders,zip_header_t * zip,const char * dst_fn)365 static void unzip_extract_symlink(llist_t **symlink_placeholders,
366 		zip_header_t *zip,
367 		const char *dst_fn)
368 {
369 	char *target;
370 
371 	die_if_bad_fnamesize(zip->fmt.ucmpsize);
372 
373 	if (zip->fmt.method == 0) {
374 		/* Method 0 - stored (not compressed) */
375 		target = xzalloc(zip->fmt.ucmpsize + 1);
376 		xread(zip_fd, target, zip->fmt.ucmpsize);
377 	} else {
378 #if 1
379 		bb_simple_error_msg_and_die("compressed symlink is not supported");
380 #else
381 		transformer_state_t xstate;
382 		init_transformer_state(&xstate);
383 		xstate.mem_output_size_max = zip->fmt.ucmpsize;
384 		/* ...unpack... */
385 		if (!xstate.mem_output_buf)
386 			WTF();
387 		target = xstate.mem_output_buf;
388 		target = xrealloc(target, xstate.mem_output_size + 1);
389 		target[xstate.mem_output_size] = '\0';
390 #endif
391 	}
392 	create_or_remember_link(symlink_placeholders,
393 			target,
394 			dst_fn,
395 			0);
396 	free(target);
397 }
398 #endif
399 
unzip_extract(zip_header_t * zip,int dst_fd)400 static void unzip_extract(zip_header_t *zip, int dst_fd)
401 {
402 	transformer_state_t xstate;
403 
404 	if (zip->fmt.method == 0) {
405 		/* Method 0 - stored (not compressed) */
406 		off_t size = zip->fmt.ucmpsize;
407 		if (size)
408 			bb_copyfd_exact_size(zip_fd, dst_fd, size);
409 		return;
410 	}
411 
412 	init_transformer_state(&xstate);
413 	xstate.bytes_in = zip->fmt.cmpsize;
414 	xstate.src_fd = zip_fd;
415 	xstate.dst_fd = dst_fd;
416 	if (zip->fmt.method == 8) {
417 		/* Method 8 - inflate */
418 		if (inflate_unzip(&xstate) < 0)
419 			bb_simple_error_msg_and_die("inflate error");
420 		/* Validate decompression - crc */
421 		if (zip->fmt.crc32 != (xstate.crc32 ^ 0xffffffffL)) {
422 			bb_simple_error_msg_and_die("crc error");
423 		}
424 	}
425 #if ENABLE_FEATURE_UNZIP_BZIP2
426 	else if (zip->fmt.method == 12) {
427 		/* Tested. Unpacker reads too much, but we use CDF
428 		 * and will seek to the correct beginning of next file.
429 		 */
430 		xstate.bytes_out = unpack_bz2_stream(&xstate);
431 		if (xstate.bytes_out < 0)
432 			bb_simple_error_msg_and_die("inflate error");
433 	}
434 #endif
435 #if ENABLE_FEATURE_UNZIP_LZMA
436 	else if (zip->fmt.method == 14) {
437 		/* Not tested yet */
438 		xstate.bytes_out = unpack_lzma_stream(&xstate);
439 		if (xstate.bytes_out < 0)
440 			bb_simple_error_msg_and_die("inflate error");
441 	}
442 #endif
443 #if ENABLE_FEATURE_UNZIP_XZ
444 	else if (zip->fmt.method == 95) {
445 		/* Not tested yet */
446 		xstate.bytes_out = unpack_xz_stream(&xstate);
447 		if (xstate.bytes_out < 0)
448 			bb_simple_error_msg_and_die("inflate error");
449 	}
450 #endif
451 	else {
452 		bb_error_msg_and_die("unsupported method %u", zip->fmt.method);
453 	}
454 
455 	/* Validate decompression - size */
456 	if (zip->fmt.ucmpsize != 0xffffffff /* seen on files with >4GB uncompressed data */
457 	 && zip->fmt.ucmpsize != xstate.bytes_out
458 	) {
459 		/* Don't die. Who knows, maybe len calculation
460 		 * was botched somewhere. After all, crc matched! */
461 		bb_simple_error_msg("bad length");
462 	}
463 }
464 
my_fgets80(char * buf80)465 static void my_fgets80(char *buf80)
466 {
467 	fflush_all();
468 	if (!fgets(buf80, 80, stdin)) {
469 		bb_simple_perror_msg_and_die("can't read standard input");
470 	}
471 }
472 
get_lstat_mode(const char * dst_fn)473 static int get_lstat_mode(const char *dst_fn)
474 {
475 	struct stat stat_buf;
476 	if (lstat(dst_fn, &stat_buf) == -1) {
477 		if (errno != ENOENT) {
478 			bb_perror_msg_and_die("can't stat '%s'",
479 				dst_fn
480 			);
481 		}
482 		/* File does not exist */
483 		return -1;
484 	}
485 	return stat_buf.st_mode;
486 }
487 
488 int unzip_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
unzip_main(int argc,char ** argv)489 int unzip_main(int argc, char **argv)
490 {
491 	enum {
492 		OPT_l = (1 << 0),
493 		OPT_x = (1 << 1),
494 		OPT_j = (1 << 2),
495 	};
496 	unsigned opts;
497 	smallint quiet = 0;
498 	IF_NOT_FEATURE_UNZIP_CDF(const) smallint verbose = 0;
499 	enum { O_PROMPT, O_NEVER, O_ALWAYS };
500 	smallint overwrite = O_PROMPT;
501 	uint32_t cdf_offset;
502 	unsigned long total_usize;
503 	unsigned long total_size;
504 	unsigned total_entries;
505 	int dst_fd = -1;
506 	char *src_fn = NULL;
507 	char *dst_fn = NULL;
508 	llist_t *zaccept = NULL;
509 	llist_t *zreject = NULL;
510 	char *base_dir = NULL;
511 #if ENABLE_FEATURE_UNZIP_CDF
512 	llist_t *symlink_placeholders = NULL;
513 #endif
514 	int i;
515 	char key_buf[80]; /* must match size used by my_fgets80 */
516 
517 /* -q, -l and -v: UnZip 5.52 of 28 February 2005, by Info-ZIP:
518  *
519  * # /usr/bin/unzip -qq -v decompress_unlzma.i.zip
520  *   204372  Defl:N    35278  83%  09-06-09 14:23  0d056252  decompress_unlzma.i
521  * # /usr/bin/unzip -q -v decompress_unlzma.i.zip
522  *  Length   Method    Size  Ratio   Date   Time   CRC-32    Name
523  * --------  ------  ------- -----   ----   ----   ------    ----
524  *   204372  Defl:N    35278  83%  09-06-09 14:23  0d056252  decompress_unlzma.i
525  * --------          -------  ---                            -------
526  *   204372            35278  83%                            1 file
527  * # /usr/bin/unzip -v decompress_unlzma.i.zip
528  * Archive:  decompress_unlzma.i.zip
529  *  Length   Method    Size  Ratio   Date   Time   CRC-32    Name
530  * --------  ------  ------- -----   ----   ----   ------    ----
531  *   204372  Defl:N    35278  83%  09-06-09 14:23  0d056252  decompress_unlzma.i
532  * --------          -------  ---                            -------
533  *   204372            35278  83%                            1 file
534  * # unzip -v decompress_unlzma.i.zip
535  * Archive:  decompress_unlzma.i.zip
536  *   Length     Date   Time    Name
537  *  --------    ----   ----    ----
538  *    204372  09-06-09 14:23   decompress_unlzma.i
539  *  --------                   -------
540  *    204372                   1 files
541  * # /usr/bin/unzip -l -qq decompress_unlzma.i.zip
542  *    204372  09-06-09 14:23   decompress_unlzma.i
543  * # /usr/bin/unzip -l -q decompress_unlzma.i.zip
544  *   Length     Date   Time    Name
545  *  --------    ----   ----    ----
546  *    204372  09-06-09 14:23   decompress_unlzma.i
547  *  --------                   -------
548  *    204372                   1 file
549  * # /usr/bin/unzip -l decompress_unlzma.i.zip
550  * Archive:  decompress_unlzma.i.zip
551  *   Length     Date   Time    Name
552  *  --------    ----   ----    ----
553  *    204372  09-06-09 14:23   decompress_unlzma.i
554  *  --------                   -------
555  *    204372                   1 file
556  */
557 
558 	opts = 0;
559 	/* '-' makes getopt return 1 for non-options */
560 	while ((i = getopt(argc, argv, "-d:lnotpqxjv")) != -1) {
561 		switch (i) {
562 		case 'd':  /* Extract to base directory */
563 			base_dir = optarg;
564 			break;
565 
566 		case 'l': /* List */
567 			opts |= OPT_l;
568 			break;
569 
570 		case 'n': /* Never overwrite existing files */
571 			overwrite = O_NEVER;
572 			break;
573 
574 		case 'o': /* Always overwrite existing files */
575 			overwrite = O_ALWAYS;
576 			break;
577 
578 		case 't': /* Extract files to /dev/null */
579 			xmove_fd(xopen("/dev/null", O_WRONLY), STDOUT_FILENO);
580 			/*fallthrough*/
581 
582 		case 'p': /* Extract files to stdout */
583 			dst_fd = STDOUT_FILENO;
584 			/*fallthrough*/
585 
586 		case 'q': /* Be quiet */
587 			quiet++;
588 			break;
589 
590 		case 'v': /* Verbose list */
591 			IF_FEATURE_UNZIP_CDF(verbose++;)
592 			opts |= OPT_l;
593 			break;
594 
595 		case 'x':
596 			opts |= OPT_x;
597 			break;
598 
599 		case 'j':
600 			opts |= OPT_j;
601 			break;
602 
603 		case 1:
604 			if (!src_fn) {
605 				/* The zip file */
606 				/* +5: space for ".zip" and NUL */
607 				src_fn = xmalloc(strlen(optarg) + 5);
608 				strcpy(src_fn, optarg);
609 			} else if (!(opts & OPT_x)) {
610 				/* Include files */
611 				llist_add_to(&zaccept, optarg);
612 			} else {
613 				/* Exclude files */
614 				llist_add_to(&zreject, optarg);
615 			}
616 			break;
617 
618 		default:
619 			bb_show_usage();
620 		}
621 	}
622 
623 #ifndef __GLIBC__
624 	/*
625 	 * This code is needed for non-GNU getopt
626 	 * which doesn't understand "-" in option string.
627 	 * The -x option won't work properly in this case:
628 	 * "unzip a.zip q -x w e" will be interpreted as
629 	 * "unzip a.zip q w e -x" = "unzip a.zip q w e"
630 	 */
631 	argv += optind;
632 	if (argv[0]) {
633 		/* +5: space for ".zip" and NUL */
634 		src_fn = xmalloc(strlen(argv[0]) + 5);
635 		strcpy(src_fn, argv[0]);
636 		while (*++argv)
637 			llist_add_to(&zaccept, *argv);
638 	}
639 #endif
640 
641 	if (!src_fn) {
642 		bb_show_usage();
643 	}
644 
645 	/* Open input file */
646 	if (LONE_DASH(src_fn)) {
647 		xdup2(STDIN_FILENO, zip_fd);
648 		/* Cannot use prompt mode since zip data is arriving on STDIN */
649 		if (overwrite == O_PROMPT)
650 			overwrite = O_NEVER;
651 	} else {
652 		static const char extn[][5] ALIGN1 = { ".zip", ".ZIP" };
653 		char *ext = src_fn + strlen(src_fn);
654 		int src_fd;
655 
656 		i = 0;
657 		for (;;) {
658 			src_fd = open(src_fn, O_RDONLY);
659 			if (src_fd >= 0)
660 				break;
661 			if (++i > 2) {
662 				*ext = '\0';
663 				bb_error_msg_and_die("can't open %s[.zip]",
664 					src_fn
665 				);
666 			}
667 			strcpy(ext, extn[i - 1]);
668 		}
669 		xmove_fd(src_fd, zip_fd);
670 	}
671 
672 	/* Change dir if necessary */
673 	if (base_dir) {
674 		/* -p DIR: try to create, errors don't matter.
675 		 * UnZip 6.00 does no multi-level mkdir (-p DIR1/DIR2 syntax),
676 		 * not using bb_make_directory() here (yet?)
677 		 */
678 		mkdir(base_dir, 0777);
679 		xchdir(base_dir);
680 	}
681 
682 	if (quiet <= 1) { /* not -qq */
683 		if (quiet == 0) {
684 			printf("Archive:  %s\n",
685 				printable_string(src_fn)
686 			);
687 		}
688 		if (opts & OPT_l) {
689 			puts(verbose ?
690 				" Length   Method    Size  Cmpr    Date    Time   CRC-32   Name\n"
691 				"--------  ------  ------- ---- ---------- ----- --------  ----"
692 				:
693 				"  Length      Date    Time    Name\n"
694 				"---------  ---------- -----   ----"
695 				);
696 		}
697 	}
698 
699 /* Example of an archive with one 0-byte long file named 'z'
700  * created by Zip 2.31 on Unix:
701  * 0000 [50 4b]03 04 0a 00 00 00 00 00 42 1a b8 3c 00 00 |PK........B..<..|
702  *       sig........ vneed flags compr mtime mdate crc32>
703  * 0010  00 00 00 00 00 00 00 00 00 00 01 00 15 00 7a 55 |..............zU|
704  *      >..... csize...... usize...... fnlen exlen fn ex>
705  * 0020  54 09 00 03 cc d3 f9 4b cc d3 f9 4b 55 78 04 00 |T......K...KUx..|
706  *      >tra_field......................................
707  * 0030  00 00 00 00[50 4b]01 02 17 03 0a 00 00 00 00 00 |....PK..........|
708  *       ........... sig........ vmade vneed flags compr
709  * 0040  42 1a b8 3c 00 00 00 00 00 00 00 00 00 00 00 00 |B..<............|
710  *       mtime mdate crc32...... csize...... usize......
711  * 0050  01 00 0d 00 00 00 00 00 00 00 00 00 a4 81 00 00 |................|
712  *       fnlen exlen clen. dnum. iattr eattr...... relofs> (eattr = rw-r--r--)
713  * 0060  00 00 7a 55 54 05 00 03 cc d3 f9 4b 55 78 00 00 |..zUT......KUx..|
714  *      >..... fn extra_field...........................
715  * 0070 [50 4b]05 06 00 00 00 00 01 00 01 00 3c 00 00 00 |PK..........<...|
716  * 0080  34 00 00 00 00 00                               |4.....|
717  */
718 	total_usize = 0;
719 	total_size = 0;
720 	total_entries = 0;
721 	cdf_offset = find_cdf_offset();	/* try to seek to the end, find CDE and CDF start */
722 	while (1) {
723 		zip_header_t zip;
724 		mode_t dir_mode = 0777;
725 #if ENABLE_FEATURE_UNZIP_CDF
726 		mode_t file_mode = 0666;
727 #endif
728 
729 		if (!ENABLE_FEATURE_UNZIP_CDF || cdf_offset == BAD_CDF_OFFSET) {
730 			/* Normally happens when input is unseekable.
731 			 *
732 			 * Valid ZIP file has Central Directory at the end
733 			 * with central directory file headers (CDFs).
734 			 * After it, there is a Central Directory End structure.
735 			 * CDFs identify what files are in the ZIP and where
736 			 * they are located. This allows ZIP readers to load
737 			 * the list of files without reading the entire ZIP archive.
738 			 * ZIP files may be appended to, only files specified in
739 			 * the CD are valid. Scanning for local file headers is
740 			 * not a correct algorithm.
741 			 *
742 			 * We try to do the above, and resort to "linear" reading
743 			 * of ZIP file only if seek failed or CDE wasn't found.
744 			 */
745 			uint32_t magic;
746 
747 			/* Check magic number */
748 			xread(zip_fd, &magic, 4);
749 			/* CDF item? Assume there are no more files, exit */
750 			if (magic == ZIP_CDF_MAGIC) {
751 				dbg("got ZIP_CDF_MAGIC");
752 				break;
753 			}
754 			/* Data descriptor? It was a streaming file, go on */
755 			if (magic == ZIP_DD_MAGIC) {
756 				dbg("got ZIP_DD_MAGIC");
757 				/* skip over duplicate crc32, cmpsize and ucmpsize */
758 				unzip_skip(3 * 4);
759 				continue;
760 			}
761 			if (magic != ZIP_FILEHEADER_MAGIC)
762 				bb_error_msg_and_die("invalid zip magic %08X", (int)magic);
763 			dbg("got ZIP_FILEHEADER_MAGIC");
764 
765 			xread(zip_fd, zip.raw, ZIP_HEADER_LEN);
766 			FIX_ENDIANNESS_ZIP(zip);
767 			if (zip.fmt.zip_flags & SWAP_LE16(0x0008)) {
768 				bb_error_msg_and_die("zip flag %s is not supported",
769 					"8 (streaming)");
770 			}
771 		}
772 #if ENABLE_FEATURE_UNZIP_CDF
773 		else {
774 			/* cdf_offset is valid (and we know the file is seekable) */
775 			cdf_header_t cdf;
776 			cdf_offset = read_next_cdf(cdf_offset, &cdf);
777 			if (cdf_offset == 0) /* EOF? */
778 				break;
779 # if 1
780 			xlseek(zip_fd,
781 				SWAP_LE32(cdf.fmt.relative_offset_of_local_header) + 4,
782 				SEEK_SET);
783 			xread(zip_fd, zip.raw, ZIP_HEADER_LEN);
784 			FIX_ENDIANNESS_ZIP(zip);
785 			if (zip.fmt.zip_flags & SWAP_LE16(0x0008)) {
786 				/* 0x0008 - streaming. [u]cmpsize can be reliably gotten
787 				 * only from Central Directory.
788 				 */
789 				zip.fmt.crc32    = cdf.fmt.crc32;
790 				zip.fmt.cmpsize  = cdf.fmt.cmpsize;
791 				zip.fmt.ucmpsize = cdf.fmt.ucmpsize;
792 			}
793 // Seen in some zipfiles: central directory 9 byte extra field contains
794 // a subfield with ID 0x5455 and 5 data bytes, which is a Unix-style UTC mtime.
795 // Local header version:
796 //  u16 0x5455 ("UT")
797 //  u16 size (1 + 4 * n)
798 //  u8  flags: bit 0:mtime is present, bit 1:atime is present, bit 2:ctime is present
799 //  u32 mtime
800 //  u32 atime
801 //  u32 ctime
802 // Central header version:
803 //  u16 0x5455 ("UT")
804 //  u16 size (5 (or 1?))
805 //  u8  flags: bit 0:mtime is present, bit 1:atime is present, bit 2:ctime is present
806 //  u32 mtime (CDF does not store atime/ctime)
807 # else
808 			/* CDF has the same data as local header, no need to read the latter...
809 			 * ...not really. An archive was seen with cdf.extra_len == 6 but
810 			 * zip.extra_len == 0.
811 			 */
812 			memcpy(&zip.fmt.version,
813 				&cdf.fmt.version_needed, ZIP_HEADER_LEN);
814 			xlseek(zip_fd,
815 				SWAP_LE32(cdf.fmt.relative_offset_of_local_header) + 4 + ZIP_HEADER_LEN,
816 				SEEK_SET);
817 # endif
818 			if ((cdf.fmt.version_made_by >> 8) == 3) {
819 				/* This archive is created on Unix */
820 				dir_mode = file_mode = (cdf.fmt.external_attributes >> 16);
821 			}
822 		}
823 #endif
824 
825 		if (zip.fmt.zip_flags & SWAP_LE16(0x0001)) {
826 			/* 0x0001 - encrypted */
827 			bb_error_msg_and_die("zip flag %s is not supported",
828 					"1 (encryption)");
829 		}
830 		dbg("File cmpsize:0x%x extra_len:0x%x ucmpsize:0x%x",
831 			(unsigned)zip.fmt.cmpsize,
832 			(unsigned)zip.fmt.extra_len,
833 			(unsigned)zip.fmt.ucmpsize
834 		);
835 
836 		/* Read filename */
837 		free(dst_fn);
838 		die_if_bad_fnamesize(zip.fmt.filename_len);
839 		dst_fn = xzalloc(zip.fmt.filename_len + 1);
840 		xread(zip_fd, dst_fn, zip.fmt.filename_len);
841 		/* Skip extra header bytes */
842 		unzip_skip(zip.fmt.extra_len);
843 
844 		/* Guard against "/abspath", "/../" and similar attacks */
845 		overlapping_strcpy(dst_fn, strip_unsafe_prefix(dst_fn));
846 
847 		/* Filter zip entries */
848 		if (find_list_entry(zreject, dst_fn)
849 		 || (zaccept && !find_list_entry(zaccept, dst_fn))
850 		) { /* Skip entry */
851 			goto skip_cmpsize;
852 		}
853 
854 		if (opts & OPT_l) {
855 			/* List entry */
856 			char dtbuf[sizeof("mm-dd-yyyy hh:mm")];
857 			sprintf(dtbuf, "%02u-%02u-%04u %02u:%02u",
858 				(zip.fmt.moddate >> 5) & 0xf,  // mm: 0x01e0
859 				(zip.fmt.moddate)      & 0x1f, // dd: 0x001f
860 				(zip.fmt.moddate >> 9) + 1980, // yy: 0xfe00
861 				(zip.fmt.modtime >> 11),       // hh: 0xf800
862 				(zip.fmt.modtime >> 5) & 0x3f  // mm: 0x07e0
863 				// seconds/2 not shown, encoded in -- 0x001f
864 			);
865 			if (!verbose) {
866 				//      "  Length      Date    Time    Name\n"
867 				//      "---------  ---------- -----   ----"
868 				printf(       "%9u  " "%s   "         "%s\n",
869 					(unsigned)zip.fmt.ucmpsize,
870 					dtbuf,
871 					printable_string(dst_fn)
872 				);
873 			} else {
874 				char method6[7];
875 				unsigned long percents;
876 
877 				sprintf(method6, "%6u", zip.fmt.method);
878 				if (zip.fmt.method == 0) {
879 					strcpy(method6, "Stored");
880 				}
881 				if (zip.fmt.method == 8) {
882 					strcpy(method6, "Defl:N");
883 					/* normal, maximum, fast, superfast */
884 					IF_DESKTOP(method6[5] = "NXFS"[(zip.fmt.zip_flags >> 1) & 3];)
885 				}
886 				percents = zip.fmt.ucmpsize - zip.fmt.cmpsize;
887 				if ((int32_t)percents < 0)
888 					percents = 0; /* happens if ucmpsize < cmpsize */
889 				percents = percents * 100;
890 				if (zip.fmt.ucmpsize)
891 					percents /= zip.fmt.ucmpsize;
892 				//      " Length   Method    Size  Cmpr    Date    Time   CRC-32   Name\n"
893 				//      "--------  ------  ------- ---- ---------- ----- --------  ----"
894 				printf(      "%8u  %s"        "%9u%4u%% " "%s "         "%08x  "  "%s\n",
895 					(unsigned)zip.fmt.ucmpsize,
896 					method6,
897 					(unsigned)zip.fmt.cmpsize,
898 					(unsigned)percents,
899 					dtbuf,
900 					zip.fmt.crc32,
901 					printable_string(dst_fn)
902 				);
903 				total_size += zip.fmt.cmpsize;
904 			}
905 			total_usize += zip.fmt.ucmpsize;
906 			goto skip_cmpsize;
907 		}
908 
909 		if (dst_fd == STDOUT_FILENO) {
910 			/* Extracting to STDOUT */
911 			goto do_extract;
912 		}
913 
914 		/* Strip paths (after -l: unzip -lj a.zip lists full names) */
915 		if (opts & OPT_j)
916 			overlapping_strcpy(dst_fn, bb_basename(dst_fn));
917 		/* Did this strip everything ("DIR/" case)? Then skip */
918 		if (!dst_fn[0])
919 			goto skip_cmpsize;
920 
921 		if (last_char_is(dst_fn, '/')) {
922 			int mode;
923 
924 			/* Extract directory */
925 			mode = get_lstat_mode(dst_fn);
926 			if (mode == -1) { /* ENOENT */
927 				if (!quiet) {
928 					printf("   creating: %s\n", printable_string(dst_fn));
929 				}
930 				unzip_create_leading_dirs(dst_fn);
931 				if (bb_make_directory(dst_fn, dir_mode, FILEUTILS_IGNORE_CHMOD_ERR)) {
932 					xfunc_die();
933 				}
934 			} else {
935 				if (!S_ISDIR(mode)) {
936 					bb_error_msg_and_die("'%s' exists but is not a %s",
937 						printable_string(dst_fn),
938 						"directory"
939 					);
940 				}
941 			}
942 			goto skip_cmpsize;
943 		}
944  check_file:
945 		/* Does target file already exist? */
946 		{
947 			int mode = get_lstat_mode(dst_fn);
948 			if (mode == -1) {
949 				/* ENOENT: does not exist */
950 				goto do_open_and_extract;
951 			}
952 			if (overwrite == O_NEVER) {
953 				goto skip_cmpsize;
954 			}
955 			if (!S_ISREG(mode)) {
956  fishy:
957 				bb_error_msg_and_die("'%s' exists but is not a %s",
958 					printable_string(dst_fn),
959 					"regular file"
960 				);
961 			}
962 			if (overwrite == O_ALWAYS) {
963 				goto do_open_and_extract;
964 			}
965 			printf("replace %s? [y]es, [n]o, [A]ll, [N]one, [r]ename: ",
966 				printable_string(dst_fn)
967 			);
968 			my_fgets80(key_buf);
969 			/* User input could take a long time. Is it still a regular file? */
970 			mode = get_lstat_mode(dst_fn);
971 			if (!S_ISREG(mode))
972 				goto fishy;
973 		}
974 
975 		/* Extract (or skip) it */
976 		switch (key_buf[0]) {
977 		case 'A':
978 			overwrite = O_ALWAYS;
979 		case 'y': /* Open file and fall into unzip */
980  do_open_and_extract:
981 			unzip_create_leading_dirs(dst_fn);
982 #if ENABLE_FEATURE_UNZIP_CDF
983 			dst_fd = -1;
984 			if (!S_ISLNK(file_mode)) {
985 				dst_fd = xopen3(dst_fn,
986 					O_WRONLY | O_CREAT | O_TRUNC | O_NOFOLLOW,
987 					file_mode);
988 			}
989 #else
990 			/* O_NOFOLLOW defends against symlink attacks */
991 			dst_fd = xopen(dst_fn, O_WRONLY | O_CREAT | O_TRUNC | O_NOFOLLOW);
992 #endif
993 			if (!quiet) {
994 				printf(/* zip.fmt.method == 0
995 					? " extracting: %s\n"
996 					: */ "  inflating: %s\n",
997 					printable_string(dst_fn)
998 				);
999 			}
1000  do_extract:
1001 #if ENABLE_FEATURE_UNZIP_CDF
1002 			if (S_ISLNK(file_mode)) {
1003 				if (dst_fd != STDOUT_FILENO) /* not -p? */
1004 					unzip_extract_symlink(&symlink_placeholders, &zip, dst_fn);
1005 			} else
1006 #endif
1007 			{
1008 				unzip_extract(&zip, dst_fd);
1009 				if (dst_fd != STDOUT_FILENO) {
1010 					/* closing STDOUT is potentially bad for future business */
1011 					close(dst_fd);
1012 				}
1013 			}
1014 			break;
1015 
1016 		case 'N':
1017 			overwrite = O_NEVER;
1018 		case 'n': /* Skip entry data */
1019  skip_cmpsize:
1020 			unzip_skip(zip.fmt.cmpsize);
1021 			break;
1022 
1023 		case 'r':
1024 			/* Prompt for new name */
1025 			printf("new name: ");
1026 			my_fgets80(key_buf);
1027 			free(dst_fn);
1028 			dst_fn = xstrdup(key_buf);
1029 			chomp(dst_fn);
1030 			goto check_file;
1031 
1032 		default:
1033 			printf("error: invalid response [%c]\n", (char)key_buf[0]);
1034 			goto check_file;
1035 		}
1036 
1037 		total_entries++;
1038 	}
1039 
1040 #if ENABLE_FEATURE_UNZIP_CDF
1041 	create_links_from_list(symlink_placeholders);
1042 #endif
1043 
1044 	if ((opts & OPT_l) && quiet <= 1) {
1045 		if (!verbose) {
1046 			//	"  Length      Date    Time    Name\n"
1047 			//	"---------  ---------- -----   ----"
1048 			printf( " --------%21s"               "-------\n"
1049 				     "%9lu%21s"               "%u files\n",
1050 				"",
1051 				total_usize, "", total_entries);
1052 		} else {
1053 			unsigned long percents = total_usize - total_size;
1054 			if ((long)percents < 0)
1055 				percents = 0; /* happens if usize < size */
1056 			percents = percents * 100;
1057 			if (total_usize)
1058 				percents /= total_usize;
1059 			//	" Length   Method    Size  Cmpr    Date    Time   CRC-32   Name\n"
1060 			//	"--------  ------  ------- ---- ---------- ----- --------  ----"
1061 			printf( "--------          ------- ----%28s"                      "----\n"
1062 				"%8lu"              "%17lu%4u%%%28s"                      "%u files\n",
1063 				"",
1064 				total_usize, total_size, (unsigned)percents, "",
1065 				total_entries);
1066 		}
1067 	}
1068 
1069 	return 0;
1070 }
1071