freebsd-skq/lib/libarchive/archive_read_support_format_zip.c
kientzle 1a60578adb libarchive 2.0
* libarchive_test program exercises many of the core features
  * Refactored old "read_extract" into new "archive_write_disk", which
    uses archive_write methods to put entries onto disk.  In particular,
    you can now use archive_write_disk to create objects on disk
    without having an archive available.
  * Pushed some security checks from bsdtar down into libarchive, where
    they can be better optimized.
  * Rearchitected the logic for creating objects on disk to reduce
    the number of system calls.  Several common cases now use a
    minimum number of system calls.
  * Virtualized some internal interfaces to provide a clearer separation
    of read and write handling and make it simpler to override key
    methods.
  * New "empty" format reader.
  * Corrected return types (this ABI breakage required the "2.0" version bump)
  * Many bug fixes.
2007-03-03 07:37:37 +00:00

809 lines
22 KiB
C

/*-
* Copyright (c) 2004 Tim Kientzle
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "archive_platform.h"
__FBSDID("$FreeBSD$");
#ifdef HAVE_SYS_STAT_H
#include <sys/stat.h>
#endif
#ifdef HAVE_ERRNO_H
#include <errno.h>
#endif
#include <stdio.h>
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#include <time.h>
#ifdef HAVE_ZLIB_H
#include <zlib.h>
#endif
#include "archive.h"
#include "archive_entry.h"
#include "archive_private.h"
#include "archive_read_private.h"
struct zip {
/* entry_bytes_remaining is the number of bytes we expect. */
int64_t entry_bytes_remaining;
int64_t entry_offset;
/* These count the number of bytes actually read for the entry. */
int64_t entry_compressed_bytes_read;
int64_t entry_uncompressed_bytes_read;
unsigned version;
unsigned system;
unsigned flags;
unsigned compression;
const char * compression_name;
time_t mtime;
time_t ctime;
time_t atime;
mode_t mode;
uid_t uid;
gid_t gid;
/* Flags to mark progress of decompression. */
char decompress_init;
char end_of_entry;
char end_of_entry_cleanup;
long crc32;
ssize_t filename_length;
ssize_t extra_length;
int64_t uncompressed_size;
int64_t compressed_size;
unsigned char *uncompressed_buffer;
size_t uncompressed_buffer_size;
#ifdef HAVE_ZLIB_H
z_stream stream;
#endif
struct archive_string pathname;
struct archive_string extra;
char format_name[64];
};
#define ZIP_LENGTH_AT_END 8
struct zip_file_header {
char signature[4];
char version[2];
char flags[2];
char compression[2];
char timedate[4];
char crc32[4];
char compressed_size[4];
char uncompressed_size[4];
char filename_length[2];
char extra_length[2];
};
static const char *compression_names[] = {
"uncompressed",
"shrinking",
"reduced-1",
"reduced-2",
"reduced-3",
"reduced-4",
"imploded",
"reserved",
"deflation"
};
static int archive_read_format_zip_bid(struct archive_read *);
static int archive_read_format_zip_cleanup(struct archive_read *);
static int archive_read_format_zip_read_data(struct archive_read *,
const void **, size_t *, off_t *);
static int archive_read_format_zip_read_data_skip(struct archive_read *a);
static int archive_read_format_zip_read_header(struct archive_read *,
struct archive_entry *);
static int i2(const char *);
static int i4(const char *);
static unsigned int u2(const char *);
static unsigned int u4(const char *);
static uint64_t u8(const char *);
static int zip_read_data_deflate(struct archive_read *a, const void **buff,
size_t *size, off_t *offset);
static int zip_read_data_none(struct archive_read *a, const void **buff,
size_t *size, off_t *offset);
static int zip_read_file_header(struct archive_read *a,
struct archive_entry *entry, struct zip *zip);
static time_t zip_time(const char *);
static void process_extra(const void* extra, struct zip* zip);
/* Largest 32-bit unsigned value, stored in a 64-bit constant. */
static const uint64_t max_uint32 = (((uint64_t)1) << 32) - 1;
int
archive_read_support_format_zip(struct archive *_a)
{
struct archive_read *a = (struct archive_read *)_a;
struct zip *zip;
int r;
zip = (struct zip *)malloc(sizeof(*zip));
if (zip == NULL) {
archive_set_error(&a->archive, ENOMEM, "Can't allocate zip data");
return (ARCHIVE_FATAL);
}
memset(zip, 0, sizeof(*zip));
r = __archive_read_register_format(a,
zip,
archive_read_format_zip_bid,
archive_read_format_zip_read_header,
archive_read_format_zip_read_data,
archive_read_format_zip_read_data_skip,
archive_read_format_zip_cleanup);
if (r != ARCHIVE_OK)
free(zip);
return (ARCHIVE_OK);
}
static int
archive_read_format_zip_bid(struct archive_read *a)
{
int bytes_read;
int bid = 0;
const void *h;
const char *p;
if (a->archive.archive_format == ARCHIVE_FORMAT_ZIP)
bid += 1;
bytes_read = (a->compression_read_ahead)(a, &h, 4);
if (bytes_read < 4)
return (-1);
p = (const char *)h;
if (p[0] == 'P' && p[1] == 'K') {
bid += 16;
if (p[2] == '\001' && p[3] == '\002')
bid += 16;
else if (p[2] == '\003' && p[3] == '\004')
bid += 16;
else if (p[2] == '\005' && p[3] == '\006')
bid += 16;
else if (p[2] == '\007' && p[3] == '\010')
bid += 16;
}
return (bid);
}
static int
archive_read_format_zip_read_header(struct archive_read *a,
struct archive_entry *entry)
{
int bytes_read;
const void *h;
const char *signature;
struct zip *zip;
a->archive.archive_format = ARCHIVE_FORMAT_ZIP;
if (a->archive.archive_format_name == NULL)
a->archive.archive_format_name = "ZIP";
zip = (struct zip *)*(a->pformat_data);
zip->decompress_init = 0;
zip->end_of_entry = 0;
zip->end_of_entry_cleanup = 0;
zip->entry_uncompressed_bytes_read = 0;
zip->entry_compressed_bytes_read = 0;
bytes_read = (a->compression_read_ahead)(a, &h, 4);
if (bytes_read < 4)
return (ARCHIVE_FATAL);
signature = (const char *)h;
if (signature[0] != 'P' || signature[1] != 'K') {
archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
"Bad ZIP file");
return (ARCHIVE_FATAL);
}
if (signature[2] == '\001' && signature[3] == '\002') {
/* Beginning of central directory. */
return (ARCHIVE_EOF);
}
if (signature[2] == '\003' && signature[3] == '\004') {
/* Regular file entry. */
return (zip_read_file_header(a, entry, zip));
}
if (signature[2] == '\005' && signature[3] == '\006') {
/* End-of-archive record. */
return (ARCHIVE_EOF);
}
if (signature[2] == '\007' && signature[3] == '\010') {
/*
* We should never encounter this record here;
* see ZIP_LENGTH_AT_END handling below for details.
*/
archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
"Bad ZIP file: Unexpected end-of-entry record");
return (ARCHIVE_FATAL);
}
archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
"Damaged ZIP file or unsupported format variant (%d,%d)",
signature[2], signature[3]);
return (ARCHIVE_FATAL);
}
int
zip_read_file_header(struct archive_read *a, struct archive_entry *entry,
struct zip *zip)
{
const struct zip_file_header *p;
const void *h;
int bytes_read;
struct stat st;
bytes_read =
(a->compression_read_ahead)(a, &h, sizeof(struct zip_file_header));
if (bytes_read < (int)sizeof(struct zip_file_header)) {
archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
"Truncated ZIP file header");
return (ARCHIVE_FATAL);
}
p = (const struct zip_file_header *)h;
zip->version = p->version[0];
zip->system = p->version[1];
zip->flags = i2(p->flags);
zip->compression = i2(p->compression);
if (zip->compression <
sizeof(compression_names)/sizeof(compression_names[0]))
zip->compression_name = compression_names[zip->compression];
else
zip->compression_name = "??";
zip->mtime = zip_time(p->timedate);
zip->ctime = 0;
zip->atime = 0;
zip->mode = 0;
zip->uid = 0;
zip->gid = 0;
zip->crc32 = i4(p->crc32);
zip->filename_length = i2(p->filename_length);
zip->extra_length = i2(p->extra_length);
zip->uncompressed_size = u4(p->uncompressed_size);
zip->compressed_size = u4(p->compressed_size);
(a->compression_read_consume)(a, sizeof(struct zip_file_header));
/* Read the filename. */
bytes_read = (a->compression_read_ahead)(a, &h, zip->filename_length);
if (bytes_read < zip->filename_length) {
archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
"Truncated ZIP file header");
return (ARCHIVE_FATAL);
}
archive_string_ensure(&zip->pathname, zip->filename_length);
archive_strncpy(&zip->pathname, (const char *)h, zip->filename_length);
(a->compression_read_consume)(a, zip->filename_length);
archive_entry_set_pathname(entry, zip->pathname.s);
if (zip->pathname.s[archive_strlen(&zip->pathname) - 1] == '/')
zip->mode = S_IFDIR | 0777;
else
zip->mode = S_IFREG | 0777;
/* Read the extra data. */
bytes_read = (a->compression_read_ahead)(a, &h, zip->extra_length);
if (bytes_read < zip->extra_length) {
archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
"Truncated ZIP file header");
return (ARCHIVE_FATAL);
}
process_extra(h, zip);
(a->compression_read_consume)(a, zip->extra_length);
/* Populate some additional entry fields: */
memset(&st, 0, sizeof(st));
st.st_mode = zip->mode;
st.st_uid = zip->uid;
st.st_gid = zip->gid;
st.st_mtime = zip->mtime;
st.st_ctime = zip->ctime;
st.st_atime = zip->atime;
st.st_size = zip->uncompressed_size;
archive_entry_copy_stat(entry, &st);
zip->entry_bytes_remaining = zip->compressed_size;
zip->entry_offset = 0;
/* Set up a more descriptive format name. */
sprintf(zip->format_name, "ZIP %d.%d (%s)",
zip->version / 10, zip->version % 10,
zip->compression_name);
a->archive.archive_format_name = zip->format_name;
return (ARCHIVE_OK);
}
/* Convert an MSDOS-style date/time into Unix-style time. */
static time_t
zip_time(const char *p)
{
int msTime, msDate;
struct tm ts;
msTime = (0xff & (unsigned)p[0]) + 256 * (0xff & (unsigned)p[1]);
msDate = (0xff & (unsigned)p[2]) + 256 * (0xff & (unsigned)p[3]);
memset(&ts, 0, sizeof(ts));
ts.tm_year = ((msDate >> 9) & 0x7f) + 80; /* Years since 1900. */
ts.tm_mon = ((msDate >> 5) & 0x0f) - 1; /* Month number. */
ts.tm_mday = msDate & 0x1f; /* Day of month. */
ts.tm_hour = (msTime >> 11) & 0x1f;
ts.tm_min = (msTime >> 5) & 0x3f;
ts.tm_sec = (msTime << 1) & 0x3e;
ts.tm_isdst = -1;
return mktime(&ts);
}
static int
archive_read_format_zip_read_data(struct archive_read *a,
const void **buff, size_t *size, off_t *offset)
{
int r;
struct zip *zip;
zip = (struct zip *)*(a->pformat_data);
/*
* If we hit end-of-entry last time, clean up and return
* ARCHIVE_EOF this time.
*/
if (zip->end_of_entry) {
if (!zip->end_of_entry_cleanup) {
if (zip->flags & ZIP_LENGTH_AT_END) {
const void *h;
const char *p;
int bytes_read =
(a->compression_read_ahead)(a, &h, 16);
if (bytes_read < 16) {
archive_set_error(&a->archive,
ARCHIVE_ERRNO_FILE_FORMAT,
"Truncated ZIP end-of-file record");
return (ARCHIVE_FATAL);
}
p = (const char *)h;
zip->crc32 = i4(p + 4);
zip->compressed_size = u4(p + 8);
zip->uncompressed_size = u4(p + 12);
bytes_read = (a->compression_read_consume)(a, 16);
}
/* Check file size, CRC against these values. */
if (zip->compressed_size != zip->entry_compressed_bytes_read) {
archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
"ZIP compressed data is wrong size");
return (ARCHIVE_WARN);
}
/* Size field only stores the lower 32 bits of the actual size. */
if ((zip->uncompressed_size & max_uint32)
!= (zip->entry_uncompressed_bytes_read & max_uint32)) {
archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
"ZIP uncompressed data is wrong size");
return (ARCHIVE_WARN);
}
/* TODO: Compute CRC. */
/*
if (zip->crc32 != zip->entry_crc32_calculated) {
archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
"ZIP data CRC error");
return (ARCHIVE_WARN);
}
*/
/* End-of-entry cleanup done. */
zip->end_of_entry_cleanup = 1;
}
return (ARCHIVE_EOF);
}
switch(zip->compression) {
case 0: /* No compression. */
r = zip_read_data_none(a, buff, size, offset);
break;
case 8: /* Deflate compression. */
r = zip_read_data_deflate(a, buff, size, offset);
break;
default: /* Unsupported compression. */
*buff = NULL;
*size = 0;
*offset = 0;
/* Return a warning. */
archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
"Unsupported ZIP compression method (%s)",
zip->compression_name);
if (zip->flags & ZIP_LENGTH_AT_END) {
/*
* ZIP_LENGTH_AT_END requires us to
* decompress the entry in order to
* skip it, but we don't know this
* compression method, so we give up.
*/
r = ARCHIVE_FATAL;
} else {
/* We know compressed size; just skip it. */
archive_read_format_zip_read_data_skip(a);
r = ARCHIVE_WARN;
}
break;
}
return (r);
}
/*
* Read "uncompressed" data. According to the current specification,
* if ZIP_LENGTH_AT_END is specified, then the size fields in the
* initial file header are supposed to be set to zero. This would, of
* course, make it impossible for us to read the archive, since we
* couldn't determine the end of the file data. Info-ZIP seems to
* include the real size fields both before and after the data in this
* case (the CRC only appears afterwards), so this works as you would
* expect.
*
* Returns ARCHIVE_OK if successful, ARCHIVE_FATAL otherwise, sets
* zip->end_of_entry if it consumes all of the data.
*/
static int
zip_read_data_none(struct archive_read *a, const void **buff,
size_t *size, off_t *offset)
{
struct zip *zip;
ssize_t bytes_avail;
zip = (struct zip *)*(a->pformat_data);
if (zip->entry_bytes_remaining == 0) {
*buff = NULL;
*size = 0;
*offset = zip->entry_offset;
zip->end_of_entry = 1;
return (ARCHIVE_OK);
}
/*
* Note: '1' here is a performance optimization.
* Recall that the decompression layer returns a count of
* available bytes; asking for more than that forces the
* decompressor to combine reads by copying data.
*/
bytes_avail = (a->compression_read_ahead)(a, buff, 1);
if (bytes_avail <= 0) {
archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
"Truncated ZIP file data");
return (ARCHIVE_FATAL);
}
if (bytes_avail > zip->entry_bytes_remaining)
bytes_avail = zip->entry_bytes_remaining;
(a->compression_read_consume)(a, bytes_avail);
*size = bytes_avail;
*offset = zip->entry_offset;
zip->entry_offset += *size;
zip->entry_bytes_remaining -= *size;
zip->entry_uncompressed_bytes_read += *size;
zip->entry_compressed_bytes_read += *size;
return (ARCHIVE_OK);
}
#ifdef HAVE_ZLIB_H
static int
zip_read_data_deflate(struct archive_read *a, const void **buff,
size_t *size, off_t *offset)
{
struct zip *zip;
ssize_t bytes_avail;
const void *compressed_buff;
int r;
zip = (struct zip *)*(a->pformat_data);
/* If the buffer hasn't been allocated, allocate it now. */
if (zip->uncompressed_buffer == NULL) {
zip->uncompressed_buffer_size = 32 * 1024;
zip->uncompressed_buffer
= (unsigned char *)malloc(zip->uncompressed_buffer_size);
if (zip->uncompressed_buffer == NULL) {
archive_set_error(&a->archive, ENOMEM,
"No memory for ZIP decompression");
return (ARCHIVE_FATAL);
}
}
/* If we haven't yet read any data, initialize the decompressor. */
if (!zip->decompress_init) {
r = inflateInit2(&zip->stream,
-15 /* Don't check for zlib header */);
if (r != Z_OK) {
archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
"Can't initialize ZIP decompression.");
return (ARCHIVE_FATAL);
}
zip->decompress_init = 1;
}
/*
* Note: '1' here is a performance optimization.
* Recall that the decompression layer returns a count of
* available bytes; asking for more than that forces the
* decompressor to combine reads by copying data.
*/
bytes_avail = (a->compression_read_ahead)(a, &compressed_buff, 1);
if (bytes_avail <= 0) {
archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
"Truncated ZIP file body");
return (ARCHIVE_FATAL);
}
/*
* A bug in zlib.h: stream.next_in should be marked 'const'
* but isn't (the library never alters data through the
* next_in pointer, only reads it). The result: this ugly
* cast to remove 'const'.
*/
zip->stream.next_in = (Bytef *)(uintptr_t)(const void *)compressed_buff;
zip->stream.avail_in = bytes_avail;
zip->stream.total_in = 0;
zip->stream.next_out = zip->uncompressed_buffer;
zip->stream.avail_out = zip->uncompressed_buffer_size;
zip->stream.total_out = 0;
r = inflate(&zip->stream, 0);
switch (r) {
case Z_OK:
break;
case Z_STREAM_END:
zip->end_of_entry = 1;
break;
case Z_MEM_ERROR:
archive_set_error(&a->archive, ENOMEM,
"Out of memory for ZIP decompression");
return (ARCHIVE_FATAL);
default:
archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
"ZIP decompression failed (%d)", r);
return (ARCHIVE_FATAL);
}
/* Consume as much as the compressor actually used. */
bytes_avail = zip->stream.total_in;
(a->compression_read_consume)(a, bytes_avail);
zip->entry_bytes_remaining -= bytes_avail;
zip->entry_compressed_bytes_read += bytes_avail;
*offset = zip->entry_offset;
*size = zip->stream.total_out;
zip->entry_uncompressed_bytes_read += *size;
*buff = zip->uncompressed_buffer;
zip->entry_offset += *size;
return (ARCHIVE_OK);
}
#else
static int
zip_read_data_deflate(struct archive_read *a, const void **buff,
size_t *size, off_t *offset)
{
*buff = NULL;
*size = 0;
*offset = 0;
archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
"libarchive compiled without deflate support (no libz)");
return (ARCHIVE_FATAL);
}
#endif
static int
archive_read_format_zip_read_data_skip(struct archive_read *a)
{
struct zip *zip;
const void *buff = NULL;
ssize_t bytes_avail;
zip = (struct zip *)*(a->pformat_data);
/*
* If the length is at the end, we have no choice but
* to decompress all the data to find the end marker.
*/
if (zip->flags & ZIP_LENGTH_AT_END) {
size_t size;
off_t offset;
int r;
do {
r = archive_read_format_zip_read_data(a, &buff,
&size, &offset);
} while (r == ARCHIVE_OK);
return (r);
}
/*
* If the length is at the beginning, we can skip the
* compressed data much more quickly.
*/
while (zip->entry_bytes_remaining > 0) {
bytes_avail = (a->compression_read_ahead)(a, &buff, 1);
if (bytes_avail <= 0) {
archive_set_error(&a->archive,
ARCHIVE_ERRNO_FILE_FORMAT,
"Truncated ZIP file body");
return (ARCHIVE_FATAL);
}
if (bytes_avail > zip->entry_bytes_remaining)
bytes_avail = zip->entry_bytes_remaining;
(a->compression_read_consume)(a, bytes_avail);
zip->entry_bytes_remaining -= bytes_avail;
}
/* This entry is finished and done. */
zip->end_of_entry_cleanup = zip->end_of_entry = 1;
return (ARCHIVE_OK);
}
static int
archive_read_format_zip_cleanup(struct archive_read *a)
{
struct zip *zip;
zip = (struct zip *)*(a->pformat_data);
if (zip->uncompressed_buffer != NULL)
free(zip->uncompressed_buffer);
archive_string_free(&(zip->pathname));
archive_string_free(&(zip->extra));
free(zip);
*(a->pformat_data) = NULL;
return (ARCHIVE_OK);
}
static int
i2(const char *p)
{
return ((0xff & (int)p[0]) + 256 * (0xff & (int)p[1]));
}
static int
i4(const char *p)
{
return ((0xffff & i2(p)) + 0x10000 * (0xffff & i2(p+2)));
}
static unsigned int
u2(const char *p)
{
return ((0xff & (unsigned int)p[0]) + 256 * (0xff & (unsigned int)p[1]));
}
static unsigned int
u4(const char *p)
{
return u2(p) + 0x10000 * u2(p+2);
}
static uint64_t
u8(const char *p)
{
return u4(p) + 0x100000000LL * u4(p+4);
}
/*
* The extra data is stored as a list of
* id1+size1+data1 + id2+size2+data2 ...
* triplets. id and size are 2 bytes each.
*/
static void
process_extra(const void* extra, struct zip* zip)
{
int offset = 0;
const char *p = (const char *)extra;
while (offset < zip->extra_length - 4)
{
unsigned short headerid = u2(p + offset);
unsigned short datasize = u2(p + offset + 2);
offset += 4;
if (offset + datasize > zip->extra_length)
break;
#ifdef DEBUG
fprintf(stderr, "Header id 0x%04x, length %d\n",
headerid, datasize);
#endif
switch (headerid) {
case 0x0001:
/* Zip64 extended information extra field. */
if (datasize >= 8)
zip->uncompressed_size = u8(p + offset);
if (datasize >= 16)
zip->compressed_size = u8(p + offset + 8);
break;
case 0x5455:
{
/* Extended time field "UT". */
int flags = p[offset];
offset++;
datasize--;
/* Flag bits indicate which dates are present. */
if (flags & 0x01)
{
#ifdef DEBUG
fprintf(stderr, "mtime: %d -> %d\n",
zip->mtime, i4(p + offset));
#endif
if (datasize < 4)
break;
zip->mtime = i4(p + offset);
offset += 4;
datasize -= 4;
}
if (flags & 0x02)
{
if (datasize < 4)
break;
zip->atime = i4(p + offset);
offset += 4;
datasize -= 4;
}
if (flags & 0x04)
{
if (datasize < 4)
break;
zip->ctime = i4(p + offset);
offset += 4;
datasize -= 4;
}
break;
}
case 0x7855:
/* Info-ZIP Unix Extra Field (type 2) "Ux". */
#ifdef DEBUG
fprintf(stderr, "uid %d gid %d\n",
i2(p + offset), i2(p + offset + 2));
#endif
if (datasize >= 2)
zip->uid = i2(p + offset);
if (datasize >= 4)
zip->gid = i2(p + offset + 2);
break;
default:
break;
}
offset += datasize;
}
#ifdef DEBUG
if (offset != zip->extra_length)
{
fprintf(stderr,
"Extra data field contents do not match reported size!");
}
#endif
}