blob: 8c4cb9881bf565184490c5a8126f4fd1a65c8ad3 [file] [log] [blame]
/* vi: set sw=4 ts=4: */
/*
* Mini unzip implementation for busybox
*
* Copyright (C) 2004 by Ed Clark
*
* Loosely based on original busybox unzip applet by Laurence Anderson.
* All options and features should work in this version.
*
* Licensed under GPLv2 or later, see file LICENSE in this source tree.
*/
/* For reference see
* http://www.pkware.com/company/standards/appnote/
* http://www.info-zip.org/pub/infozip/doc/appnote-iz-latest.zip
*
* TODO
* Zip64 + other methods
*/
//config:config UNZIP
//config: bool "unzip (26 kb)"
//config: default y
//config: help
//config: unzip will list or extract files from a ZIP archive,
//config: commonly found on DOS/WIN systems. The default behavior
//config: (with no options) is to extract the archive into the
//config: current directory.
//config:
//config:config FEATURE_UNZIP_CDF
//config: bool "Read and use Central Directory data"
//config: default y
//config: depends on UNZIP
//config: help
//config: If you know that you only need to deal with simple
//config: ZIP files without deleted/updated files, SFX archives etc,
//config: you can reduce code size by unselecting this option.
//config: To support less trivial ZIPs, say Y.
//config:
//config:config FEATURE_UNZIP_BZIP2
//config: bool "Support compression method 12 (bzip2)"
//config: default y
//config: depends on FEATURE_UNZIP_CDF && DESKTOP
// FEATURE_UNZIP_CDF is needed, otherwise we can't find start of next file
// DESKTOP is needed to get back uncompressed length
//config:
//config:config FEATURE_UNZIP_LZMA
//config: bool "Support compression method 14 (lzma)"
//config: default y
//config: depends on FEATURE_UNZIP_CDF && DESKTOP
//config:
//config:config FEATURE_UNZIP_XZ
//config: bool "Support compression method 95 (xz)"
//config: default y
//config: depends on FEATURE_UNZIP_CDF && DESKTOP
//applet:IF_UNZIP(APPLET(unzip, BB_DIR_USR_BIN, BB_SUID_DROP))
//kbuild:lib-$(CONFIG_UNZIP) += unzip.o
//usage:#define unzip_trivial_usage
//usage: "[-lnojpq] FILE[.zip] [FILE]... [-x FILE...] [-d DIR]"
//usage:#define unzip_full_usage "\n\n"
//usage: "Extract FILEs from ZIP archive\n"
//usage: "\n -l List contents (with -q for short form)"
//usage: "\n -n Never overwrite files (default: ask)"
//usage: "\n -o Overwrite"
//usage: "\n -j Do not restore paths"
//usage: "\n -p Print to stdout"
//usage: "\n -q Quiet"
//usage: "\n -x FILE Exclude FILEs"
//usage: "\n -d DIR Extract into DIR"
#include "libbb.h"
#include "bb_archive.h"
#if 0
# define dbg(...) bb_error_msg(__VA_ARGS__)
#else
# define dbg(...) ((void)0)
#endif
enum {
#if BB_BIG_ENDIAN
ZIP_FILEHEADER_MAGIC = 0x504b0304,
ZIP_CDF_MAGIC = 0x504b0102, /* CDF item */
ZIP_CDE_MAGIC = 0x504b0506, /* End of CDF */
ZIP_DD_MAGIC = 0x504b0708,
#else
ZIP_FILEHEADER_MAGIC = 0x04034b50,
ZIP_CDF_MAGIC = 0x02014b50,
ZIP_CDE_MAGIC = 0x06054b50,
ZIP_DD_MAGIC = 0x08074b50,
#endif
};
#define ZIP_HEADER_LEN 26
typedef union {
uint8_t raw[ZIP_HEADER_LEN];
struct {
uint16_t version; /* 0-1 */
uint16_t zip_flags; /* 2-3 */
uint16_t method; /* 4-5 */
uint16_t modtime; /* 6-7 */
uint16_t moddate; /* 8-9 */
uint32_t crc32 PACKED; /* 10-13 */
uint32_t cmpsize PACKED; /* 14-17 */
uint32_t ucmpsize PACKED; /* 18-21 */
uint16_t filename_len; /* 22-23 */
uint16_t extra_len; /* 24-25 */
/* filename follows (not NUL terminated) */
/* extra field follows */
/* data follows */
} fmt PACKED;
} zip_header_t; /* PACKED - gcc 4.2.1 doesn't like it (spews warning) */
#define FIX_ENDIANNESS_ZIP(zip) \
do { if (BB_BIG_ENDIAN) { \
(zip).fmt.method = SWAP_LE16((zip).fmt.method ); \
(zip).fmt.crc32 = SWAP_LE32((zip).fmt.crc32 ); \
(zip).fmt.cmpsize = SWAP_LE32((zip).fmt.cmpsize ); \
(zip).fmt.ucmpsize = SWAP_LE32((zip).fmt.ucmpsize ); \
(zip).fmt.filename_len = SWAP_LE16((zip).fmt.filename_len); \
(zip).fmt.extra_len = SWAP_LE16((zip).fmt.extra_len ); \
}} while (0)
#define CDF_HEADER_LEN 42
typedef union {
uint8_t raw[CDF_HEADER_LEN];
struct {
/* uint32_t signature; 50 4b 01 02 */
uint16_t version_made_by; /* 0-1 */
uint16_t version_needed; /* 2-3 */
uint16_t cdf_flags; /* 4-5 */
uint16_t method; /* 6-7 */
uint16_t modtime; /* 8-9 */
uint16_t moddate; /* 10-11 */
uint32_t crc32; /* 12-15 */
uint32_t cmpsize; /* 16-19 */
uint32_t ucmpsize; /* 20-23 */
uint16_t filename_len; /* 24-25 */
uint16_t extra_len; /* 26-27 */
uint16_t file_comment_length; /* 28-29 */
uint16_t disk_number_start; /* 30-31 */
uint16_t internal_attributes; /* 32-33 */
uint32_t external_attributes PACKED; /* 34-37 */
uint32_t relative_offset_of_local_header PACKED; /* 38-41 */
/* filename follows (not NUL terminated) */
/* extra field follows */
/* file comment follows */
} fmt PACKED;
} cdf_header_t;
#define FIX_ENDIANNESS_CDF(cdf) \
do { if (BB_BIG_ENDIAN) { \
(cdf).fmt.version_made_by = SWAP_LE16((cdf).fmt.version_made_by); \
(cdf).fmt.version_needed = SWAP_LE16((cdf).fmt.version_needed ); \
(cdf).fmt.method = SWAP_LE16((cdf).fmt.method ); \
(cdf).fmt.modtime = SWAP_LE16((cdf).fmt.modtime ); \
(cdf).fmt.moddate = SWAP_LE16((cdf).fmt.moddate ); \
(cdf).fmt.crc32 = SWAP_LE32((cdf).fmt.crc32 ); \
(cdf).fmt.cmpsize = SWAP_LE32((cdf).fmt.cmpsize ); \
(cdf).fmt.ucmpsize = SWAP_LE32((cdf).fmt.ucmpsize ); \
(cdf).fmt.filename_len = SWAP_LE16((cdf).fmt.filename_len ); \
(cdf).fmt.extra_len = SWAP_LE16((cdf).fmt.extra_len ); \
(cdf).fmt.file_comment_length = SWAP_LE16((cdf).fmt.file_comment_length); \
(cdf).fmt.external_attributes = SWAP_LE32((cdf).fmt.external_attributes); \
}} while (0)
#define CDE_LEN 16
typedef union {
uint8_t raw[CDE_LEN];
struct {
/* uint32_t signature; 50 4b 05 06 */
uint16_t this_disk_no;
uint16_t disk_with_cdf_no;
uint16_t cdf_entries_on_this_disk;
uint16_t cdf_entries_total;
uint32_t cdf_size;
uint32_t cdf_offset;
/* uint16_t archive_comment_length; */
/* archive comment follows */
} fmt PACKED;
} cde_t;
#define FIX_ENDIANNESS_CDE(cde) \
do { if (BB_BIG_ENDIAN) { \
(cde).fmt.cdf_offset = SWAP_LE32((cde).fmt.cdf_offset); \
}} while (0)
struct BUG {
/* Check the offset of the last element, not the length. This leniency
* allows for poor packing, whereby the overall struct may be too long,
* even though the elements are all in the right place.
*/
char BUG_zip_header_must_be_26_bytes[
offsetof(zip_header_t, fmt.extra_len) + 2
== ZIP_HEADER_LEN ? 1 : -1];
char BUG_cdf_header_must_be_42_bytes[
offsetof(cdf_header_t, fmt.relative_offset_of_local_header) + 4
== CDF_HEADER_LEN ? 1 : -1];
char BUG_cde_must_be_16_bytes[
sizeof(cde_t) == CDE_LEN ? 1 : -1];
};
enum { zip_fd = 3 };
/* This value means that we failed to find CDF */
#define BAD_CDF_OFFSET ((uint32_t)0xffffffff)
#if !ENABLE_FEATURE_UNZIP_CDF
# define find_cdf_offset() BAD_CDF_OFFSET
#else
/* Seen in the wild:
* Self-extracting PRO2K3XP_32.exe contains 19078464 byte zip archive,
* where CDE was nearly 48 kbytes before EOF.
* (Surprisingly, it also apparently has *another* CDE structure
* closer to the end, with bogus cdf_offset).
* To make extraction work, bumped PEEK_FROM_END from 16k to 64k.
*/
#define PEEK_FROM_END (64*1024)
/* NB: does not preserve file position! */
static uint32_t find_cdf_offset(void)
{
cde_t cde;
unsigned char *buf;
unsigned char *p;
off_t end;
uint32_t found;
end = lseek(zip_fd, 0, SEEK_END);
if (end == (off_t) -1)
return BAD_CDF_OFFSET;
end -= PEEK_FROM_END;
if (end < 0)
end = 0;
dbg("Looking for cdf_offset starting from 0x%"OFF_FMT"x", end);
xlseek(zip_fd, end, SEEK_SET);
buf = xzalloc(PEEK_FROM_END);
full_read(zip_fd, buf, PEEK_FROM_END);
found = BAD_CDF_OFFSET;
p = buf;
while (p <= buf + PEEK_FROM_END - CDE_LEN - 4) {
if (*p != 'P') {
p++;
continue;
}
if (*++p != 'K')
continue;
if (*++p != 5)
continue;
if (*++p != 6)
continue;
/* we found CDE! */
memcpy(cde.raw, p + 1, CDE_LEN);
FIX_ENDIANNESS_CDE(cde);
/*
* I've seen .ZIP files with seemingly valid CDEs
* where cdf_offset points past EOF - ??
* This check ignores such CDEs:
*/
if (cde.fmt.cdf_offset < end + (p - buf)) {
found = cde.fmt.cdf_offset;
dbg("Possible cdf_offset:0x%x at 0x%"OFF_FMT"x",
(unsigned)found, end + (p-3 - buf));
dbg(" cdf_offset+cdf_size:0x%x",
(unsigned)(found + SWAP_LE32(cde.fmt.cdf_size)));
/*
* We do not "break" here because only the last CDE is valid.
* I've seen a .zip archive which contained a .zip file,
* uncompressed, and taking the first CDE was using
* the CDE inside that file!
*/
}
}
free(buf);
dbg("Found cdf_offset:0x%x", (unsigned)found);
return found;
};
static uint32_t read_next_cdf(uint32_t cdf_offset, cdf_header_t *cdf)
{
uint32_t magic;
if (cdf_offset == BAD_CDF_OFFSET)
return cdf_offset;
dbg("Reading CDF at 0x%x", (unsigned)cdf_offset);
xlseek(zip_fd, cdf_offset, SEEK_SET);
xread(zip_fd, &magic, 4);
/* Central Directory End? Assume CDF has ended.
* (more correct method is to use cde.cdf_entries_total counter)
*/
if (magic == ZIP_CDE_MAGIC) {
dbg("got ZIP_CDE_MAGIC");
return 0; /* EOF */
}
xread(zip_fd, cdf->raw, CDF_HEADER_LEN);
FIX_ENDIANNESS_CDF(*cdf);
dbg(" filename_len:%u extra_len:%u file_comment_length:%u",
(unsigned)cdf->fmt.filename_len,
(unsigned)cdf->fmt.extra_len,
(unsigned)cdf->fmt.file_comment_length
);
cdf_offset += 4 + CDF_HEADER_LEN
+ cdf->fmt.filename_len
+ cdf->fmt.extra_len
+ cdf->fmt.file_comment_length;
return cdf_offset;
};
#endif
static void die_if_bad_fnamesize(unsigned sz)
{
if (sz > 0xfff) /* more than 4k?! no funny business please */
bb_simple_error_msg_and_die("bad archive");
}
static void unzip_skip(off_t skip)
{
if (skip != 0)
if (lseek(zip_fd, skip, SEEK_CUR) == (off_t)-1)
bb_copyfd_exact_size(zip_fd, -1, skip);
}
static void unzip_create_leading_dirs(const char *fn)
{
/* Create all leading directories */
char *name = xstrdup(fn);
/* mode of -1: set mode according to umask */
if (bb_make_directory(dirname(name), -1, FILEUTILS_RECUR)) {
xfunc_die(); /* bb_make_directory is noisy */
}
free(name);
}
#if ENABLE_FEATURE_UNZIP_CDF
static void unzip_extract_symlink(llist_t **symlink_placeholders,
zip_header_t *zip,
const char *dst_fn)
{
char *target;
die_if_bad_fnamesize(zip->fmt.ucmpsize);
if (zip->fmt.method == 0) {
/* Method 0 - stored (not compressed) */
target = xzalloc(zip->fmt.ucmpsize + 1);
xread(zip_fd, target, zip->fmt.ucmpsize);
} else {
#if 1
bb_simple_error_msg_and_die("compressed symlink is not supported");
#else
transformer_state_t xstate;
init_transformer_state(&xstate);
xstate.mem_output_size_max = zip->fmt.ucmpsize;
/* ...unpack... */
if (!xstate.mem_output_buf)
WTF();
target = xstate.mem_output_buf;
target = xrealloc(target, xstate.mem_output_size + 1);
target[xstate.mem_output_size] = '\0';
#endif
}
create_or_remember_link(symlink_placeholders,
target,
dst_fn,
0);
free(target);
}
#endif
static void unzip_extract(zip_header_t *zip, int dst_fd)
{
transformer_state_t xstate;
if (zip->fmt.method == 0) {
/* Method 0 - stored (not compressed) */
off_t size = zip->fmt.ucmpsize;
if (size)
bb_copyfd_exact_size(zip_fd, dst_fd, size);
return;
}
init_transformer_state(&xstate);
xstate.bytes_in = zip->fmt.cmpsize;
xstate.src_fd = zip_fd;
xstate.dst_fd = dst_fd;
if (zip->fmt.method == 8) {
/* Method 8 - inflate */
if (inflate_unzip(&xstate) < 0)
bb_simple_error_msg_and_die("inflate error");
/* Validate decompression - crc */
if (zip->fmt.crc32 != (xstate.crc32 ^ 0xffffffffL)) {
bb_simple_error_msg_and_die("crc error");
}
}
#if ENABLE_FEATURE_UNZIP_BZIP2
else if (zip->fmt.method == 12) {
/* Tested. Unpacker reads too much, but we use CDF
* and will seek to the correct beginning of next file.
*/
xstate.bytes_out = unpack_bz2_stream(&xstate);
if (xstate.bytes_out < 0)
bb_simple_error_msg_and_die("inflate error");
}
#endif
#if ENABLE_FEATURE_UNZIP_LZMA
else if (zip->fmt.method == 14) {
/* Not tested yet */
xstate.bytes_out = unpack_lzma_stream(&xstate);
if (xstate.bytes_out < 0)
bb_simple_error_msg_and_die("inflate error");
}
#endif
#if ENABLE_FEATURE_UNZIP_XZ
else if (zip->fmt.method == 95) {
/* Not tested yet */
xstate.bytes_out = unpack_xz_stream(&xstate);
if (xstate.bytes_out < 0)
bb_simple_error_msg_and_die("inflate error");
}
#endif
else {
bb_error_msg_and_die("unsupported method %u", zip->fmt.method);
}
/* Validate decompression - size */
if (zip->fmt.ucmpsize != xstate.bytes_out) {
/* Don't die. Who knows, maybe len calculation
* was botched somewhere. After all, crc matched! */
bb_simple_error_msg("bad length");
}
}
static void my_fgets80(char *buf80)
{
fflush_all();
if (!fgets(buf80, 80, stdin)) {
bb_simple_perror_msg_and_die("can't read standard input");
}
}
static int get_lstat_mode(const char *dst_fn)
{
struct stat stat_buf;
if (lstat(dst_fn, &stat_buf) == -1) {
if (errno != ENOENT) {
bb_perror_msg_and_die("can't stat '%s'",
dst_fn
);
}
/* File does not exist */
return -1;
}
return stat_buf.st_mode;
}
int unzip_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int unzip_main(int argc, char **argv)
{
enum {
OPT_l = (1 << 0),
OPT_x = (1 << 1),
OPT_j = (1 << 2),
};
unsigned opts;
smallint quiet = 0;
IF_NOT_FEATURE_UNZIP_CDF(const) smallint verbose = 0;
enum { O_PROMPT, O_NEVER, O_ALWAYS };
smallint overwrite = O_PROMPT;
uint32_t cdf_offset;
unsigned long total_usize;
unsigned long total_size;
unsigned total_entries;
int dst_fd = -1;
char *src_fn = NULL;
char *dst_fn = NULL;
llist_t *zaccept = NULL;
llist_t *zreject = NULL;
char *base_dir = NULL;
#if ENABLE_FEATURE_UNZIP_CDF
llist_t *symlink_placeholders = NULL;
#endif
int i;
char key_buf[80]; /* must match size used by my_fgets80 */
/* -q, -l and -v: UnZip 5.52 of 28 February 2005, by Info-ZIP:
*
* # /usr/bin/unzip -qq -v decompress_unlzma.i.zip
* 204372 Defl:N 35278 83% 09-06-09 14:23 0d056252 decompress_unlzma.i
* # /usr/bin/unzip -q -v decompress_unlzma.i.zip
* Length Method Size Ratio Date Time CRC-32 Name
* -------- ------ ------- ----- ---- ---- ------ ----
* 204372 Defl:N 35278 83% 09-06-09 14:23 0d056252 decompress_unlzma.i
* -------- ------- --- -------
* 204372 35278 83% 1 file
* # /usr/bin/unzip -v decompress_unlzma.i.zip
* Archive: decompress_unlzma.i.zip
* Length Method Size Ratio Date Time CRC-32 Name
* -------- ------ ------- ----- ---- ---- ------ ----
* 204372 Defl:N 35278 83% 09-06-09 14:23 0d056252 decompress_unlzma.i
* -------- ------- --- -------
* 204372 35278 83% 1 file
* # unzip -v decompress_unlzma.i.zip
* Archive: decompress_unlzma.i.zip
* Length Date Time Name
* -------- ---- ---- ----
* 204372 09-06-09 14:23 decompress_unlzma.i
* -------- -------
* 204372 1 files
* # /usr/bin/unzip -l -qq decompress_unlzma.i.zip
* 204372 09-06-09 14:23 decompress_unlzma.i
* # /usr/bin/unzip -l -q decompress_unlzma.i.zip
* Length Date Time Name
* -------- ---- ---- ----
* 204372 09-06-09 14:23 decompress_unlzma.i
* -------- -------
* 204372 1 file
* # /usr/bin/unzip -l decompress_unlzma.i.zip
* Archive: decompress_unlzma.i.zip
* Length Date Time Name
* -------- ---- ---- ----
* 204372 09-06-09 14:23 decompress_unlzma.i
* -------- -------
* 204372 1 file
*/
opts = 0;
/* '-' makes getopt return 1 for non-options */
while ((i = getopt(argc, argv, "-d:lnopqxjv")) != -1) {
switch (i) {
case 'd': /* Extract to base directory */
base_dir = optarg;
break;
case 'l': /* List */
opts |= OPT_l;
break;
case 'n': /* Never overwrite existing files */
overwrite = O_NEVER;
break;
case 'o': /* Always overwrite existing files */
overwrite = O_ALWAYS;
break;
case 'p': /* Extract files to stdout and fall through to set verbosity */
dst_fd = STDOUT_FILENO;
case 'q': /* Be quiet */
quiet++;
break;
case 'v': /* Verbose list */
IF_FEATURE_UNZIP_CDF(verbose++;)
opts |= OPT_l;
break;
case 'x':
opts |= OPT_x;
break;
case 'j':
opts |= OPT_j;
break;
case 1:
if (!src_fn) {
/* The zip file */
/* +5: space for ".zip" and NUL */
src_fn = xmalloc(strlen(optarg) + 5);
strcpy(src_fn, optarg);
} else if (!(opts & OPT_x)) {
/* Include files */
llist_add_to(&zaccept, optarg);
} else {
/* Exclude files */
llist_add_to(&zreject, optarg);
}
break;
default:
bb_show_usage();
}
}
#ifndef __GLIBC__
/*
* This code is needed for non-GNU getopt
* which doesn't understand "-" in option string.
* The -x option won't work properly in this case:
* "unzip a.zip q -x w e" will be interpreted as
* "unzip a.zip q w e -x" = "unzip a.zip q w e"
*/
argv += optind;
if (argv[0]) {
/* +5: space for ".zip" and NUL */
src_fn = xmalloc(strlen(argv[0]) + 5);
strcpy(src_fn, argv[0]);
while (*++argv)
llist_add_to(&zaccept, *argv);
}
#endif
if (!src_fn) {
bb_show_usage();
}
/* Open input file */
if (LONE_DASH(src_fn)) {
xdup2(STDIN_FILENO, zip_fd);
/* Cannot use prompt mode since zip data is arriving on STDIN */
if (overwrite == O_PROMPT)
overwrite = O_NEVER;
} else {
static const char extn[][5] ALIGN1 = { ".zip", ".ZIP" };
char *ext = src_fn + strlen(src_fn);
int src_fd;
i = 0;
for (;;) {
src_fd = open(src_fn, O_RDONLY);
if (src_fd >= 0)
break;
if (++i > 2) {
*ext = '\0';
bb_error_msg_and_die("can't open %s[.zip]",
src_fn
);
}
strcpy(ext, extn[i - 1]);
}
xmove_fd(src_fd, zip_fd);
}
/* Change dir if necessary */
if (base_dir)
xchdir(base_dir);
if (quiet <= 1) { /* not -qq */
if (quiet == 0) {
printf("Archive: %s\n",
printable_string(src_fn)
);
}
if (opts & OPT_l) {
puts(verbose ?
" Length Method Size Cmpr Date Time CRC-32 Name\n"
"-------- ------ ------- ---- ---------- ----- -------- ----"
:
" Length Date Time Name\n"
"--------- ---------- ----- ----"
);
}
}
/* Example of an archive with one 0-byte long file named 'z'
* created by Zip 2.31 on Unix:
* 0000 [50 4b]03 04 0a 00 00 00 00 00 42 1a b8 3c 00 00 |PK........B..<..|
* sig........ vneed flags compr mtime mdate crc32>
* 0010 00 00 00 00 00 00 00 00 00 00 01 00 15 00 7a 55 |..............zU|
* >..... csize...... usize...... fnlen exlen fn ex>
* 0020 54 09 00 03 cc d3 f9 4b cc d3 f9 4b 55 78 04 00 |T......K...KUx..|
* >tra_field......................................
* 0030 00 00 00 00[50 4b]01 02 17 03 0a 00 00 00 00 00 |....PK..........|
* ........... sig........ vmade vneed flags compr
* 0040 42 1a b8 3c 00 00 00 00 00 00 00 00 00 00 00 00 |B..<............|
* mtime mdate crc32...... csize...... usize......
* 0050 01 00 0d 00 00 00 00 00 00 00 00 00 a4 81 00 00 |................|
* fnlen exlen clen. dnum. iattr eattr...... relofs> (eattr = rw-r--r--)
* 0060 00 00 7a 55 54 05 00 03 cc d3 f9 4b 55 78 00 00 |..zUT......KUx..|
* >..... fn extra_field...........................
* 0070 [50 4b]05 06 00 00 00 00 01 00 01 00 3c 00 00 00 |PK..........<...|
* 0080 34 00 00 00 00 00 |4.....|
*/
total_usize = 0;
total_size = 0;
total_entries = 0;
cdf_offset = find_cdf_offset(); /* try to seek to the end, find CDE and CDF start */
while (1) {
zip_header_t zip;
mode_t dir_mode = 0777;
#if ENABLE_FEATURE_UNZIP_CDF
mode_t file_mode = 0666;
#endif
if (!ENABLE_FEATURE_UNZIP_CDF || cdf_offset == BAD_CDF_OFFSET) {
/* Normally happens when input is unseekable.
*
* Valid ZIP file has Central Directory at the end
* with central directory file headers (CDFs).
* After it, there is a Central Directory End structure.
* CDFs identify what files are in the ZIP and where
* they are located. This allows ZIP readers to load
* the list of files without reading the entire ZIP archive.
* ZIP files may be appended to, only files specified in
* the CD are valid. Scanning for local file headers is
* not a correct algorithm.
*
* We try to do the above, and resort to "linear" reading
* of ZIP file only if seek failed or CDE wasn't found.
*/
uint32_t magic;
/* Check magic number */
xread(zip_fd, &magic, 4);
/* CDF item? Assume there are no more files, exit */
if (magic == ZIP_CDF_MAGIC) {
dbg("got ZIP_CDF_MAGIC");
break;
}
/* Data descriptor? It was a streaming file, go on */
if (magic == ZIP_DD_MAGIC) {
dbg("got ZIP_DD_MAGIC");
/* skip over duplicate crc32, cmpsize and ucmpsize */
unzip_skip(3 * 4);
continue;
}
if (magic != ZIP_FILEHEADER_MAGIC)
bb_error_msg_and_die("invalid zip magic %08X", (int)magic);
dbg("got ZIP_FILEHEADER_MAGIC");
xread(zip_fd, zip.raw, ZIP_HEADER_LEN);
FIX_ENDIANNESS_ZIP(zip);
if (zip.fmt.zip_flags & SWAP_LE16(0x0008)) {
bb_error_msg_and_die("zip flag %s is not supported",
"8 (streaming)");
}
}
#if ENABLE_FEATURE_UNZIP_CDF
else {
/* cdf_offset is valid (and we know the file is seekable) */
cdf_header_t cdf;
cdf_offset = read_next_cdf(cdf_offset, &cdf);
if (cdf_offset == 0) /* EOF? */
break;
# if 1
xlseek(zip_fd,
SWAP_LE32(cdf.fmt.relative_offset_of_local_header) + 4,
SEEK_SET);
xread(zip_fd, zip.raw, ZIP_HEADER_LEN);
FIX_ENDIANNESS_ZIP(zip);
if (zip.fmt.zip_flags & SWAP_LE16(0x0008)) {
/* 0x0008 - streaming. [u]cmpsize can be reliably gotten
* only from Central Directory.
*/
zip.fmt.crc32 = cdf.fmt.crc32;
zip.fmt.cmpsize = cdf.fmt.cmpsize;
zip.fmt.ucmpsize = cdf.fmt.ucmpsize;
}
// Seen in some zipfiles: central directory 9 byte extra field contains
// a subfield with ID 0x5455 and 5 data bytes, which is a Unix-style UTC mtime.
// Local header version:
// u16 0x5455 ("UT")
// u16 size (1 + 4 * n)
// u8 flags: bit 0:mtime is present, bit 1:atime is present, bit 2:ctime is present
// u32 mtime
// u32 atime
// u32 ctime
// Central header version:
// u16 0x5455 ("UT")
// u16 size (5 (or 1?))
// u8 flags: bit 0:mtime is present, bit 1:atime is present, bit 2:ctime is present
// u32 mtime (CDF does not store atime/ctime)
# else
/* CDF has the same data as local header, no need to read the latter...
* ...not really. An archive was seen with cdf.extra_len == 6 but
* zip.extra_len == 0.
*/
memcpy(&zip.fmt.version,
&cdf.fmt.version_needed, ZIP_HEADER_LEN);
xlseek(zip_fd,
SWAP_LE32(cdf.fmt.relative_offset_of_local_header) + 4 + ZIP_HEADER_LEN,
SEEK_SET);
# endif
if ((cdf.fmt.version_made_by >> 8) == 3) {
/* This archive is created on Unix */
dir_mode = file_mode = (cdf.fmt.external_attributes >> 16);
}
}
#endif
if (zip.fmt.zip_flags & SWAP_LE16(0x0001)) {
/* 0x0001 - encrypted */
bb_error_msg_and_die("zip flag %s is not supported",
"1 (encryption)");
}
dbg("File cmpsize:0x%x extra_len:0x%x ucmpsize:0x%x",
(unsigned)zip.fmt.cmpsize,
(unsigned)zip.fmt.extra_len,
(unsigned)zip.fmt.ucmpsize
);
/* Read filename */
free(dst_fn);
die_if_bad_fnamesize(zip.fmt.filename_len);
dst_fn = xzalloc(zip.fmt.filename_len + 1);
xread(zip_fd, dst_fn, zip.fmt.filename_len);
/* Skip extra header bytes */
unzip_skip(zip.fmt.extra_len);
/* Guard against "/abspath", "/../" and similar attacks */
overlapping_strcpy(dst_fn, strip_unsafe_prefix(dst_fn));
/* Filter zip entries */
if (find_list_entry(zreject, dst_fn)
|| (zaccept && !find_list_entry(zaccept, dst_fn))
) { /* Skip entry */
goto skip_cmpsize;
}
if (opts & OPT_l) {
/* List entry */
char dtbuf[sizeof("mm-dd-yyyy hh:mm")];
sprintf(dtbuf, "%02u-%02u-%04u %02u:%02u",
(zip.fmt.moddate >> 5) & 0xf, // mm: 0x01e0
(zip.fmt.moddate) & 0x1f, // dd: 0x001f
(zip.fmt.moddate >> 9) + 1980, // yy: 0xfe00
(zip.fmt.modtime >> 11), // hh: 0xf800
(zip.fmt.modtime >> 5) & 0x3f // mm: 0x07e0
// seconds/2 not shown, encoded in -- 0x001f
);
if (!verbose) {
// " Length Date Time Name\n"
// "--------- ---------- ----- ----"
printf( "%9u " "%s " "%s\n",
(unsigned)zip.fmt.ucmpsize,
dtbuf,
printable_string(dst_fn)
);
} else {
char method6[7];
unsigned long percents;
sprintf(method6, "%6u", zip.fmt.method);
if (zip.fmt.method == 0) {
strcpy(method6, "Stored");
}
if (zip.fmt.method == 8) {
strcpy(method6, "Defl:N");
/* normal, maximum, fast, superfast */
IF_DESKTOP(method6[5] = "NXFS"[(zip.fmt.zip_flags >> 1) & 3];)
}
percents = zip.fmt.ucmpsize - zip.fmt.cmpsize;
if ((int32_t)percents < 0)
percents = 0; /* happens if ucmpsize < cmpsize */
percents = percents * 100;
if (zip.fmt.ucmpsize)
percents /= zip.fmt.ucmpsize;
// " Length Method Size Cmpr Date Time CRC-32 Name\n"
// "-------- ------ ------- ---- ---------- ----- -------- ----"
printf( "%8u %s" "%9u%4u%% " "%s " "%08x " "%s\n",
(unsigned)zip.fmt.ucmpsize,
method6,
(unsigned)zip.fmt.cmpsize,
(unsigned)percents,
dtbuf,
zip.fmt.crc32,
printable_string(dst_fn)
);
total_size += zip.fmt.cmpsize;
}
total_usize += zip.fmt.ucmpsize;
goto skip_cmpsize;
}
if (dst_fd == STDOUT_FILENO) {
/* Extracting to STDOUT */
goto do_extract;
}
/* Strip paths (after -l: unzip -lj a.zip lists full names) */
if (opts & OPT_j)
overlapping_strcpy(dst_fn, bb_basename(dst_fn));
/* Did this strip everything ("DIR/" case)? Then skip */
if (!dst_fn[0])
goto skip_cmpsize;
if (last_char_is(dst_fn, '/')) {
int mode;
/* Extract directory */
mode = get_lstat_mode(dst_fn);
if (mode == -1) { /* ENOENT */
if (!quiet) {
printf(" creating: %s\n", printable_string(dst_fn));
}
unzip_create_leading_dirs(dst_fn);
if (bb_make_directory(dst_fn, dir_mode, FILEUTILS_IGNORE_CHMOD_ERR)) {
xfunc_die();
}
} else {
if (!S_ISDIR(mode)) {
bb_error_msg_and_die("'%s' exists but is not a %s",
printable_string(dst_fn),
"directory"
);
}
}
goto skip_cmpsize;
}
check_file:
/* Does target file already exist? */
{
int mode = get_lstat_mode(dst_fn);
if (mode == -1) {
/* ENOENT: does not exist */
goto do_open_and_extract;
}
if (overwrite == O_NEVER) {
goto skip_cmpsize;
}
if (!S_ISREG(mode)) {
fishy:
bb_error_msg_and_die("'%s' exists but is not a %s",
printable_string(dst_fn),
"regular file"
);
}
if (overwrite == O_ALWAYS) {
goto do_open_and_extract;
}
printf("replace %s? [y]es, [n]o, [A]ll, [N]one, [r]ename: ",
printable_string(dst_fn)
);
my_fgets80(key_buf);
/* User input could take a long time. Is it still a regular file? */
mode = get_lstat_mode(dst_fn);
if (!S_ISREG(mode))
goto fishy;
}
/* Extract (or skip) it */
switch (key_buf[0]) {
case 'A':
overwrite = O_ALWAYS;
case 'y': /* Open file and fall into unzip */
do_open_and_extract:
unzip_create_leading_dirs(dst_fn);
#if ENABLE_FEATURE_UNZIP_CDF
dst_fd = -1;
if (!S_ISLNK(file_mode)) {
dst_fd = xopen3(dst_fn,
O_WRONLY | O_CREAT | O_TRUNC | O_NOFOLLOW,
file_mode);
}
#else
/* O_NOFOLLOW defends against symlink attacks */
dst_fd = xopen(dst_fn, O_WRONLY | O_CREAT | O_TRUNC | O_NOFOLLOW);
#endif
do_extract:
if (!quiet) {
printf(/* zip.fmt.method == 0
? " extracting: %s\n"
: */ " inflating: %s\n",
printable_string(dst_fn)
);
}
#if ENABLE_FEATURE_UNZIP_CDF
if (S_ISLNK(file_mode)) {
if (dst_fd != STDOUT_FILENO) /* not -p? */
unzip_extract_symlink(&symlink_placeholders, &zip, dst_fn);
} else
#endif
{
unzip_extract(&zip, dst_fd);
if (dst_fd != STDOUT_FILENO) {
/* closing STDOUT is potentially bad for future business */
close(dst_fd);
}
}
break;
case 'N':
overwrite = O_NEVER;
case 'n': /* Skip entry data */
skip_cmpsize:
unzip_skip(zip.fmt.cmpsize);
break;
case 'r':
/* Prompt for new name */
printf("new name: ");
my_fgets80(key_buf);
free(dst_fn);
dst_fn = xstrdup(key_buf);
chomp(dst_fn);
goto check_file;
default:
printf("error: invalid response [%c]\n", (char)key_buf[0]);
goto check_file;
}
total_entries++;
}
#if ENABLE_FEATURE_UNZIP_CDF
create_links_from_list(symlink_placeholders);
#endif
if ((opts & OPT_l) && quiet <= 1) {
if (!verbose) {
// " Length Date Time Name\n"
// "--------- ---------- ----- ----"
printf( " --------%21s" "-------\n"
"%9lu%21s" "%u files\n",
"",
total_usize, "", total_entries);
} else {
unsigned long percents = total_usize - total_size;
if ((long)percents < 0)
percents = 0; /* happens if usize < size */
percents = percents * 100;
if (total_usize)
percents /= total_usize;
// " Length Method Size Cmpr Date Time CRC-32 Name\n"
// "-------- ------ ------- ---- ---------- ----- -------- ----"
printf( "-------- ------- ----%28s" "----\n"
"%8lu" "%17lu%4u%%%28s" "%u files\n",
"",
total_usize, total_size, (unsigned)percents, "",
total_entries);
}
}
return 0;
}