550 lines
14 KiB
C
550 lines
14 KiB
C
/*-
|
|
* Copyright (c) 2003-2007 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
|
|
#ifdef HAVE_STDLIB_H
|
|
#include <stdlib.h>
|
|
#endif
|
|
#ifdef HAVE_STRING_H
|
|
#include <string.h>
|
|
#endif
|
|
#ifdef HAVE_UNISTD_H
|
|
#include <unistd.h>
|
|
#endif
|
|
#ifdef HAVE_ZLIB_H
|
|
#include <zlib.h>
|
|
#endif
|
|
|
|
#include "archive.h"
|
|
#include "archive_private.h"
|
|
#include "archive_read_private.h"
|
|
|
|
#ifdef HAVE_ZLIB_H
|
|
struct private_data {
|
|
z_stream stream;
|
|
unsigned char *uncompressed_buffer;
|
|
size_t uncompressed_buffer_size;
|
|
unsigned char *read_next;
|
|
int64_t total_out;
|
|
unsigned long crc;
|
|
char header_done;
|
|
char eof; /* True = found end of compressed data. */
|
|
};
|
|
|
|
static int finish(struct archive_read *);
|
|
static ssize_t read_ahead(struct archive_read *, const void **, size_t);
|
|
static ssize_t read_consume(struct archive_read *, size_t);
|
|
static int drive_decompressor(struct archive_read *a, struct private_data *);
|
|
#endif
|
|
|
|
/* These two functions are defined even if we lack the library. See below. */
|
|
static int bid(const void *, size_t);
|
|
static int init(struct archive_read *, const void *, size_t);
|
|
|
|
int
|
|
archive_read_support_compression_gzip(struct archive *_a)
|
|
{
|
|
struct archive_read *a = (struct archive_read *)_a;
|
|
if (__archive_read_register_compression(a, bid, init) != NULL)
|
|
return (ARCHIVE_OK);
|
|
return (ARCHIVE_FATAL);
|
|
}
|
|
|
|
/*
|
|
* Test whether we can handle this data.
|
|
*
|
|
* This logic returns zero if any part of the signature fails. It
|
|
* also tries to Do The Right Thing if a very short buffer prevents us
|
|
* from verifying as much as we would like.
|
|
*/
|
|
static int
|
|
bid(const void *buff, size_t len)
|
|
{
|
|
const unsigned char *buffer;
|
|
int bits_checked;
|
|
|
|
if (len < 1)
|
|
return (0);
|
|
|
|
buffer = (const unsigned char *)buff;
|
|
bits_checked = 0;
|
|
if (buffer[0] != 037) /* Verify first ID byte. */
|
|
return (0);
|
|
bits_checked += 8;
|
|
if (len < 2)
|
|
return (bits_checked);
|
|
|
|
if (buffer[1] != 0213) /* Verify second ID byte. */
|
|
return (0);
|
|
bits_checked += 8;
|
|
if (len < 3)
|
|
return (bits_checked);
|
|
|
|
if (buffer[2] != 8) /* Compression must be 'deflate'. */
|
|
return (0);
|
|
bits_checked += 8;
|
|
if (len < 4)
|
|
return (bits_checked);
|
|
|
|
if ((buffer[3] & 0xE0)!= 0) /* No reserved flags set. */
|
|
return (0);
|
|
bits_checked += 3;
|
|
if (len < 5)
|
|
return (bits_checked);
|
|
|
|
/*
|
|
* TODO: Verify more; in particular, gzip has an optional
|
|
* header CRC, which would give us 16 more verified bits. We
|
|
* may also be able to verify certain constraints on other
|
|
* fields.
|
|
*/
|
|
|
|
return (bits_checked);
|
|
}
|
|
|
|
|
|
#ifndef HAVE_ZLIB_H
|
|
|
|
/*
|
|
* If we don't have the library on this system, we can't actually do the
|
|
* decompression. We can, however, still detect compressed archives
|
|
* and emit a useful message.
|
|
*/
|
|
static int
|
|
init(struct archive_read *a, const void *buff, size_t n)
|
|
{
|
|
(void)a; /* UNUSED */
|
|
(void)buff; /* UNUSED */
|
|
(void)n; /* UNUSED */
|
|
|
|
archive_set_error(&a->archive, -1,
|
|
"This version of libarchive was compiled without gzip support");
|
|
return (ARCHIVE_FATAL);
|
|
}
|
|
|
|
|
|
#else
|
|
|
|
/*
|
|
* Setup the callbacks.
|
|
*/
|
|
static int
|
|
init(struct archive_read *a, const void *buff, size_t n)
|
|
{
|
|
struct private_data *state;
|
|
int ret;
|
|
|
|
a->archive.compression_code = ARCHIVE_COMPRESSION_GZIP;
|
|
a->archive.compression_name = "gzip";
|
|
|
|
state = (struct private_data *)malloc(sizeof(*state));
|
|
if (state == NULL) {
|
|
archive_set_error(&a->archive, ENOMEM,
|
|
"Can't allocate data for %s decompression",
|
|
a->archive.compression_name);
|
|
return (ARCHIVE_FATAL);
|
|
}
|
|
memset(state, 0, sizeof(*state));
|
|
|
|
state->crc = crc32(0L, NULL, 0);
|
|
state->header_done = 0; /* We've not yet begun to parse header... */
|
|
|
|
state->uncompressed_buffer_size = 64 * 1024;
|
|
state->uncompressed_buffer = (unsigned char *)malloc(state->uncompressed_buffer_size);
|
|
state->stream.next_out = state->uncompressed_buffer;
|
|
state->read_next = state->uncompressed_buffer;
|
|
state->stream.avail_out = state->uncompressed_buffer_size;
|
|
|
|
if (state->uncompressed_buffer == NULL) {
|
|
archive_set_error(&a->archive, ENOMEM,
|
|
"Can't allocate %s decompression buffers",
|
|
a->archive.compression_name);
|
|
free(state);
|
|
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'.
|
|
*/
|
|
state->stream.next_in = (Bytef *)(uintptr_t)(const void *)buff;
|
|
state->stream.avail_in = n;
|
|
|
|
a->decompressor->read_ahead = read_ahead;
|
|
a->decompressor->consume = read_consume;
|
|
a->decompressor->skip = NULL; /* not supported */
|
|
a->decompressor->finish = finish;
|
|
|
|
/*
|
|
* TODO: Do I need to parse the gzip header before calling
|
|
* inflateInit2()? In particular, one of the header bytes
|
|
* marks "best compression" or "fastest", which may be
|
|
* appropriate for setting the second parameter here.
|
|
* However, I think the only penalty for not setting it
|
|
* correctly is wasted memory. If this is necessary, it
|
|
* should probably go into drive_decompressor() below.
|
|
*/
|
|
|
|
/* Initialize compression library. */
|
|
ret = inflateInit2(&(state->stream),
|
|
-15 /* Don't check for zlib header */);
|
|
if (ret == Z_OK) {
|
|
a->decompressor->data = state;
|
|
return (ARCHIVE_OK);
|
|
}
|
|
|
|
/* Library setup failed: Clean up. */
|
|
archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
|
|
"Internal error initializing %s library",
|
|
a->archive.compression_name);
|
|
free(state->uncompressed_buffer);
|
|
free(state);
|
|
|
|
/* Override the error message if we know what really went wrong. */
|
|
switch (ret) {
|
|
case Z_STREAM_ERROR:
|
|
archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
|
|
"Internal error initializing compression library: "
|
|
"invalid setup parameter");
|
|
break;
|
|
case Z_MEM_ERROR:
|
|
archive_set_error(&a->archive, ENOMEM,
|
|
"Internal error initializing compression library: "
|
|
"out of memory");
|
|
break;
|
|
case Z_VERSION_ERROR:
|
|
archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
|
|
"Internal error initializing compression library: "
|
|
"invalid library version");
|
|
break;
|
|
}
|
|
|
|
return (ARCHIVE_FATAL);
|
|
}
|
|
|
|
/*
|
|
* Return a block of data from the decompression buffer. Decompress more
|
|
* as necessary.
|
|
*/
|
|
static ssize_t
|
|
read_ahead(struct archive_read *a, const void **p, size_t min)
|
|
{
|
|
struct private_data *state;
|
|
size_t read_avail, was_avail;
|
|
int ret;
|
|
|
|
state = (struct private_data *)a->decompressor->data;
|
|
if (!a->client_reader) {
|
|
archive_set_error(&a->archive, ARCHIVE_ERRNO_PROGRAMMER,
|
|
"No read callback is registered? "
|
|
"This is probably an internal programming error.");
|
|
return (ARCHIVE_FATAL);
|
|
}
|
|
|
|
read_avail = state->stream.next_out - state->read_next;
|
|
|
|
if (read_avail + state->stream.avail_out < min) {
|
|
memmove(state->uncompressed_buffer, state->read_next,
|
|
read_avail);
|
|
state->read_next = state->uncompressed_buffer;
|
|
state->stream.next_out = state->read_next + read_avail;
|
|
state->stream.avail_out
|
|
= state->uncompressed_buffer_size - read_avail;
|
|
}
|
|
|
|
while (read_avail < min && /* Haven't satisfied min. */
|
|
read_avail < state->uncompressed_buffer_size) { /* !full */
|
|
was_avail = read_avail;
|
|
if ((ret = drive_decompressor(a, state)) < ARCHIVE_OK)
|
|
return (ret);
|
|
if (ret == ARCHIVE_EOF)
|
|
break; /* Break on EOF even if we haven't met min. */
|
|
read_avail = state->stream.next_out - state->read_next;
|
|
if (was_avail == read_avail) /* No progress? */
|
|
break;
|
|
}
|
|
|
|
*p = state->read_next;
|
|
return (read_avail);
|
|
}
|
|
|
|
/*
|
|
* Mark a previously-returned block of data as read.
|
|
*/
|
|
static ssize_t
|
|
read_consume(struct archive_read *a, size_t n)
|
|
{
|
|
struct private_data *state;
|
|
|
|
state = (struct private_data *)a->decompressor->data;
|
|
a->archive.file_position += n;
|
|
state->read_next += n;
|
|
if (state->read_next > state->stream.next_out)
|
|
__archive_errx(1, "Request to consume too many "
|
|
"bytes from gzip decompressor");
|
|
return (n);
|
|
}
|
|
|
|
/*
|
|
* Clean up the decompressor.
|
|
*/
|
|
static int
|
|
finish(struct archive_read *a)
|
|
{
|
|
struct private_data *state;
|
|
int ret;
|
|
|
|
state = (struct private_data *)a->decompressor->data;
|
|
ret = ARCHIVE_OK;
|
|
switch (inflateEnd(&(state->stream))) {
|
|
case Z_OK:
|
|
break;
|
|
default:
|
|
archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
|
|
"Failed to clean up %s compressor",
|
|
a->archive.compression_name);
|
|
ret = ARCHIVE_FATAL;
|
|
}
|
|
|
|
free(state->uncompressed_buffer);
|
|
free(state);
|
|
|
|
a->decompressor->data = NULL;
|
|
return (ret);
|
|
}
|
|
|
|
/*
|
|
* Utility function to pull data through decompressor, reading input
|
|
* blocks as necessary.
|
|
*/
|
|
static int
|
|
drive_decompressor(struct archive_read *a, struct private_data *state)
|
|
{
|
|
ssize_t ret;
|
|
size_t decompressed, total_decompressed;
|
|
int count, flags, header_state;
|
|
unsigned char *output;
|
|
unsigned char b;
|
|
const void *read_buf;
|
|
|
|
if (state->eof)
|
|
return (ARCHIVE_EOF);
|
|
flags = 0;
|
|
count = 0;
|
|
header_state = 0;
|
|
total_decompressed = 0;
|
|
for (;;) {
|
|
if (state->stream.avail_in == 0) {
|
|
read_buf = state->stream.next_in;
|
|
ret = (a->client_reader)(&a->archive, a->client_data,
|
|
&read_buf);
|
|
state->stream.next_in = (unsigned char *)(uintptr_t)read_buf;
|
|
if (ret < 0) {
|
|
/*
|
|
* TODO: Find a better way to handle
|
|
* this read failure.
|
|
*/
|
|
goto fatal;
|
|
}
|
|
if (ret == 0 && total_decompressed == 0) {
|
|
archive_set_error(&a->archive, EIO,
|
|
"Premature end of %s compressed data",
|
|
a->archive.compression_name);
|
|
return (ARCHIVE_FATAL);
|
|
}
|
|
a->archive.raw_position += ret;
|
|
state->stream.avail_in = ret;
|
|
}
|
|
|
|
if (!state->header_done) {
|
|
/*
|
|
* If still parsing the header, interpret the
|
|
* next byte.
|
|
*/
|
|
b = *(state->stream.next_in++);
|
|
state->stream.avail_in--;
|
|
|
|
/*
|
|
* Yes, this is somewhat crude, but it works,
|
|
* GZip format isn't likely to change anytime
|
|
* in the near future, and header parsing is
|
|
* certainly not a performance issue, so
|
|
* there's little point in making this more
|
|
* elegant. Of course, if you see an easy way
|
|
* to make this more elegant, please let me
|
|
* know.. ;-)
|
|
*/
|
|
switch (header_state) {
|
|
case 0: /* First byte of signature. */
|
|
if (b != 037)
|
|
goto fatal;
|
|
header_state = 1;
|
|
break;
|
|
case 1: /* Second byte of signature. */
|
|
if (b != 0213)
|
|
goto fatal;
|
|
header_state = 2;
|
|
break;
|
|
case 2: /* Compression type must be 8. */
|
|
if (b != 8)
|
|
goto fatal;
|
|
header_state = 3;
|
|
break;
|
|
case 3: /* GZip flags. */
|
|
flags = b;
|
|
header_state = 4;
|
|
break;
|
|
case 4: case 5: case 6: case 7: /* Mod time. */
|
|
header_state++;
|
|
break;
|
|
case 8: /* Deflate flags. */
|
|
header_state = 9;
|
|
break;
|
|
case 9: /* OS. */
|
|
header_state = 10;
|
|
break;
|
|
case 10: /* Optional Extra: First byte of Length. */
|
|
if ((flags & 4)) {
|
|
count = 255 & (int)b;
|
|
header_state = 11;
|
|
break;
|
|
}
|
|
/*
|
|
* Fall through if there is no
|
|
* Optional Extra field.
|
|
*/
|
|
case 11: /* Optional Extra: Second byte of Length. */
|
|
if ((flags & 4)) {
|
|
count = (0xff00 & ((int)b << 8)) | count;
|
|
header_state = 12;
|
|
break;
|
|
}
|
|
/*
|
|
* Fall through if there is no
|
|
* Optional Extra field.
|
|
*/
|
|
case 12: /* Optional Extra Field: counted length. */
|
|
if ((flags & 4)) {
|
|
--count;
|
|
if (count == 0) header_state = 13;
|
|
else header_state = 12;
|
|
break;
|
|
}
|
|
/*
|
|
* Fall through if there is no
|
|
* Optional Extra field.
|
|
*/
|
|
case 13: /* Optional Original Filename. */
|
|
if ((flags & 8)) {
|
|
if (b == 0) header_state = 14;
|
|
else header_state = 13;
|
|
break;
|
|
}
|
|
/*
|
|
* Fall through if no Optional
|
|
* Original Filename.
|
|
*/
|
|
case 14: /* Optional Comment. */
|
|
if ((flags & 16)) {
|
|
if (b == 0) header_state = 15;
|
|
else header_state = 14;
|
|
break;
|
|
}
|
|
/* Fall through if no Optional Comment. */
|
|
case 15: /* Optional Header CRC: First byte. */
|
|
if ((flags & 2)) {
|
|
header_state = 16;
|
|
break;
|
|
}
|
|
/* Fall through if no Optional Header CRC. */
|
|
case 16: /* Optional Header CRC: Second byte. */
|
|
if ((flags & 2)) {
|
|
header_state = 17;
|
|
break;
|
|
}
|
|
/* Fall through if no Optional Header CRC. */
|
|
case 17: /* First byte of compressed data. */
|
|
state->header_done = 1; /* done with header */
|
|
state->stream.avail_in++;
|
|
state->stream.next_in--;
|
|
}
|
|
|
|
/*
|
|
* TODO: Consider moving the inflateInit2 call
|
|
* here so it can include the compression type
|
|
* from the header?
|
|
*/
|
|
} else {
|
|
output = state->stream.next_out;
|
|
|
|
/* Decompress some data. */
|
|
ret = inflate(&(state->stream), 0);
|
|
decompressed = state->stream.next_out - output;
|
|
|
|
/* Accumulate the CRC of the uncompressed data. */
|
|
state->crc = crc32(state->crc, output, decompressed);
|
|
|
|
/* Accumulate the total bytes of output. */
|
|
state->total_out += decompressed;
|
|
total_decompressed += decompressed;
|
|
|
|
switch (ret) {
|
|
case Z_OK: /* Decompressor made some progress. */
|
|
if (decompressed > 0)
|
|
return (ARCHIVE_OK);
|
|
break;
|
|
case Z_STREAM_END: /* Found end of stream. */
|
|
/*
|
|
* TODO: Verify gzip trailer
|
|
* (uncompressed length and CRC).
|
|
*/
|
|
state->eof = 1;
|
|
return (ARCHIVE_OK);
|
|
default:
|
|
/* Any other return value is an error. */
|
|
goto fatal;
|
|
}
|
|
}
|
|
}
|
|
return (ARCHIVE_OK);
|
|
|
|
/* Return a fatal error. */
|
|
fatal:
|
|
archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
|
|
"%s decompression failed", a->archive.compression_name);
|
|
return (ARCHIVE_FATAL);
|
|
}
|
|
|
|
#endif /* HAVE_ZLIB_H */
|