freebsd-dev/lib/libarchive/archive_read_support_format_zip.c
Tim Kientzle ee8a341ef4 If we don't know the file size, leave the file size unset.
If it's not a regular file, don't return any data, even if the size is unknown.

Update the Zip test with a hand-tweaked Zip archive that has a
directory (with length-at-end set), a regular file without
length-at-end set, and a regular file with length-at-end set and a bad
CRC.  Update the test code to verify that the file size is unset
for the regular file with length-at-end.

MFC after:	7 days
2008-10-21 05:08:35 +00:00

906 lines
25 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_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"
#include "archive_endian.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;
/* Running CRC32 of the decompressed data */
unsigned long entry_crc32;
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;
unsigned 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;
char stream_valid;
#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 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);
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)
{
const char *p;
const void *buff;
size_t bytes_avail;
if ((p = __archive_read_ahead(a, 4)) == NULL)
return (-1);
/*
* Bid of 30 here is: 16 bits for "PK",
* next 16-bit field has four options (-2 bits).
* 16 + 16-2 = 30.
*/
if (p[0] == 'P' && p[1] == 'K') {
if ((p[2] == '\001' && p[3] == '\002')
|| (p[2] == '\003' && p[3] == '\004')
|| (p[2] == '\005' && p[3] == '\006')
|| (p[2] == '\007' && p[3] == '\010')
|| (p[2] == '0' && p[3] == '0'))
return (30);
}
/*
* Attempt to handle self-extracting archives
* by noting a PE header and searching forward
* up to 64k for a 'PK\003\004' marker.
*/
if (p[0] == 'M' && p[1] == 'Z') {
/*
* TODO: Additional checks that this really is a PE
* file before we invoke the 128k lookahead below.
* No point in allocating a bigger lookahead buffer
* if we don't need to.
*/
/*
* TODO: Of course, the compression layer lookahead
* buffers aren't dynamically sized yet; they should be.
*/
bytes_avail = (a->decompressor->read_ahead)(a, &buff, 128*1024);
p = (const char *)buff;
/*
* TODO: Optimize by jumping forward based on values
* in the PE header. Note that we don't need to be
* exact, but we mustn't skip too far. The search
* below will compensate if we undershoot. Skipping
* will also reduce the chance of false positives
* (which is not really all that high to begin with,
* so maybe skipping isn't really necessary).
*/
while (p < bytes_avail + (const char *)buff) {
if (p[0] == 'P' && p[1] == 'K' /* "PK" signature */
&& p[2] == 3 && p[3] == 4 /* File entry */
&& p[8] == 8 /* compression == deflate */
&& p[9] == 0 /* High byte of compression */
)
{
return (30);
}
++p;
}
}
return (0);
}
/*
* Search forward for a "PK\003\004" file header. This handles the
* case of self-extracting archives, where there is an executable
* prepended to the ZIP archive.
*/
static int
skip_sfx(struct archive_read *a)
{
const void *h;
const char *p, *q;
size_t skip, bytes;
/*
* TODO: We should be able to skip forward by a bunch
* by lifting some values from the PE header. We don't
* need to be exact (we're still going to search forward
* to find the header), but it will speed things up and
* reduce the chance of a false positive.
*/
for (;;) {
bytes = (a->decompressor->read_ahead)(a, &h, 4096);
if (bytes < 4)
return (ARCHIVE_FATAL);
p = h;
q = p + bytes;
/*
* Scan ahead until we find something that looks
* like the zip header.
*/
while (p + 4 < q) {
switch (p[3]) {
case '\004':
/* TODO: Additional verification here. */
if (memcmp("PK\003\004", p, 4) == 0) {
skip = p - (const char *)h;
(a->decompressor->consume)(a, skip);
return (ARCHIVE_OK);
}
p += 4;
break;
case '\003': p += 1; break;
case 'K': p += 2; break;
case 'P': p += 3; break;
default: p += 4; break;
}
}
skip = p - (const char *)h;
(a->decompressor->consume)(a, skip);
}
}
static int
archive_read_format_zip_read_header(struct archive_read *a,
struct archive_entry *entry)
{
const void *h;
const char *signature;
struct zip *zip;
int r = ARCHIVE_OK, r1;
a->archive.archive_format = ARCHIVE_FORMAT_ZIP;
if (a->archive.archive_format_name == NULL)
a->archive.archive_format_name = "ZIP";
zip = (struct zip *)(a->format->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;
zip->entry_crc32 = crc32(0, NULL, 0);
if ((h = __archive_read_ahead(a, 4)) == NULL)
return (ARCHIVE_FATAL);
signature = (const char *)h;
if (signature[0] == 'M' && signature[1] == 'Z') {
/* This is an executable? Must be self-extracting... */
r = skip_sfx(a);
if (r < ARCHIVE_WARN)
return (r);
if ((h = __archive_read_ahead(a, 4)) == NULL)
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);
}
/*
* "PK00" signature is used for "split" archives that
* only have a single segment. This means we can just
* skip the PK00; the first real file header should follow.
*/
if (signature[2] == '0' && signature[3] == '0') {
(a->decompressor->consume)(a, 4);
if ((h = __archive_read_ahead(a, 4)) == NULL)
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. */
r1 = zip_read_file_header(a, entry, zip);
if (r1 != ARCHIVE_OK)
return (r1);
return (r);
}
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;
if ((p = __archive_read_ahead(a, sizeof *p)) == NULL) {
archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
"Truncated ZIP file header");
return (ARCHIVE_FATAL);
}
zip->version = p->version[0];
zip->system = p->version[1];
zip->flags = archive_le16dec(p->flags);
zip->compression = archive_le16dec(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 = archive_le32dec(p->crc32);
zip->filename_length = archive_le16dec(p->filename_length);
zip->extra_length = archive_le16dec(p->extra_length);
zip->uncompressed_size = archive_le32dec(p->uncompressed_size);
zip->compressed_size = archive_le32dec(p->compressed_size);
(a->decompressor->consume)(a, sizeof(struct zip_file_header));
/* Read the filename. */
if ((h = __archive_read_ahead(a, zip->filename_length)) == NULL) {
archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
"Truncated ZIP file header");
return (ARCHIVE_FATAL);
}
if (archive_string_ensure(&zip->pathname, zip->filename_length) == NULL)
__archive_errx(1, "Out of memory");
archive_strncpy(&zip->pathname, h, zip->filename_length);
(a->decompressor->consume)(a, zip->filename_length);
archive_entry_set_pathname(entry, zip->pathname.s);
if (zip->pathname.s[archive_strlen(&zip->pathname) - 1] == '/')
zip->mode = AE_IFDIR | 0777;
else
zip->mode = AE_IFREG | 0777;
/* Read the extra data. */
if ((h = __archive_read_ahead(a, zip->extra_length)) == NULL) {
archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
"Truncated ZIP file header");
return (ARCHIVE_FATAL);
}
process_extra(h, zip);
(a->decompressor->consume)(a, zip->extra_length);
/* Populate some additional entry fields: */
archive_entry_set_mode(entry, zip->mode);
archive_entry_set_uid(entry, zip->uid);
archive_entry_set_gid(entry, zip->gid);
archive_entry_set_mtime(entry, zip->mtime, 0);
archive_entry_set_ctime(entry, zip->ctime, 0);
archive_entry_set_atime(entry, zip->atime, 0);
/* Set the size only if it's meaningful. */
if (0 == (zip->flags & ZIP_LENGTH_AT_END))
archive_entry_set_size(entry, zip->uncompressed_size);
zip->entry_bytes_remaining = zip->compressed_size;
zip->entry_offset = 0;
/* If there's no body, force read_data() to return EOF immediately. */
if (0 == (zip->flags & ZIP_LENGTH_AT_END)
&& zip->entry_bytes_remaining < 1)
zip->end_of_entry = 1;
/* 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->format->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 char *p;
if ((p = __archive_read_ahead(a, 16)) == NULL) {
archive_set_error(&a->archive,
ARCHIVE_ERRNO_FILE_FORMAT,
"Truncated ZIP end-of-file record");
return (ARCHIVE_FATAL);
}
zip->crc32 = archive_le32dec(p + 4);
zip->compressed_size = archive_le32dec(p + 8);
zip->uncompressed_size = archive_le32dec(p + 12);
(a->decompressor->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 & UINT32_MAX)
!= (zip->entry_uncompressed_bytes_read & UINT32_MAX)) {
archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
"ZIP uncompressed data is wrong size");
return (ARCHIVE_WARN);
}
/* Check computed CRC against header */
if (zip->crc32 != zip->entry_crc32) {
archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
"ZIP bad CRC: 0x%lx should be 0x%lx",
zip->entry_crc32, zip->crc32);
return (ARCHIVE_WARN);
}
/* End-of-entry cleanup done. */
zip->end_of_entry_cleanup = 1;
}
*offset = zip->entry_uncompressed_bytes_read;
*size = 0;
*buff = NULL;
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 can't decompress this entry, but we will
* be able to skip() it and try the next entry. */
r = ARCHIVE_WARN;
}
break;
}
if (r != ARCHIVE_OK)
return (r);
/* Update checksum */
if (*size)
zip->entry_crc32 =
crc32(zip->entry_crc32, *buff, *size);
/* Return EOF immediately if this is a non-regular file. */
if (AE_IFREG != (zip->mode & AE_IFMT))
return (ARCHIVE_EOF);
return (ARCHIVE_OK);
}
/*
* 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->format->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->decompressor->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->decompressor->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->format->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) {
if (zip->stream_valid)
r = inflateReset(&zip->stream);
else
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);
}
/* Stream structure has been set up. */
zip->stream_valid = 1;
/* We've initialized decompression for this stream. */
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->decompressor->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->decompressor->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;
off_t bytes_skipped;
zip = (struct zip *)(a->format->data);
/* If we've already read to end of data, we're done. */
if (zip->end_of_entry_cleanup)
return (ARCHIVE_OK);
/*
* 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.
*/
bytes_skipped = (a->decompressor->skip)(a, zip->entry_bytes_remaining);
if (bytes_skipped < 0)
return (ARCHIVE_FATAL);
/* 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->format->data);
#ifdef HAVE_ZLIB_H
if (zip->stream_valid)
inflateEnd(&zip->stream);
#endif
free(zip->uncompressed_buffer);
archive_string_free(&(zip->pathname));
archive_string_free(&(zip->extra));
free(zip);
(a->format->data) = NULL;
return (ARCHIVE_OK);
}
/*
* 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 = archive_le16dec(p + offset);
unsigned short datasize = archive_le16dec(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 = archive_le64dec(p + offset);
if (datasize >= 16)
zip->compressed_size = archive_le64dec(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: %lld -> %d\n",
(long long)zip->mtime,
archive_le32dec(p + offset));
#endif
if (datasize < 4)
break;
zip->mtime = archive_le32dec(p + offset);
offset += 4;
datasize -= 4;
}
if (flags & 0x02)
{
if (datasize < 4)
break;
zip->atime = archive_le32dec(p + offset);
offset += 4;
datasize -= 4;
}
if (flags & 0x04)
{
if (datasize < 4)
break;
zip->ctime = archive_le32dec(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",
archive_le16dec(p + offset),
archive_le16dec(p + offset + 2));
#endif
if (datasize >= 2)
zip->uid = archive_le16dec(p + offset);
if (datasize >= 4)
zip->gid = archive_le16dec(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
}