* grub-core/Makefile.core.def (xzio): New module.

* grub-core/io/xzio.c: New file.
	* grub-core/lib/xzembed/xz.h: New file (from xembed).
	* grub-core/lib/xzembed/xz_config.h: Likewise.
	* grub-core/lib/xzembed/xz_dec_bcj.c: Likewise.
	* grub-core/lib/xzembed/xz_dec_lzma2.c: Likewise.
	* grub-core/lib/xzembed/xz_dec_stream.c: Likewise.
	* grub-core/lib/xzembed/xz_lzma2.h: Likewise.
	* grub-core/lib/xzembed/xz_private.h: Likewise.
	* grub-core/lib/xzembed/xz_stream.h: Likewise.
	* include/grub/file.h (grub_file_filter_id): New compression filter
	GRUB_FILE_FILTER_XZIO.
This commit is contained in:
Szymon Janc 2010-09-05 17:12:13 +02:00 committed by Vladimir 'phcoder' Serbinenko
parent 82a8506214
commit f0aff67c47
12 changed files with 3676 additions and 1 deletions

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@ -1,3 +1,18 @@
2010-09-05 Szymon Janc <szymon@janc.net.pl>
* grub-core/Makefile.core.def (xzio): New module.
* grub-core/io/xzio.c: New file.
* grub-core/lib/xzembed/xz.h: New file (from xembed).
* grub-core/lib/xzembed/xz_config.h: Likewise.
* grub-core/lib/xzembed/xz_dec_bcj.c: Likewise.
* grub-core/lib/xzembed/xz_dec_lzma2.c: Likewise.
* grub-core/lib/xzembed/xz_dec_stream.c: Likewise.
* grub-core/lib/xzembed/xz_lzma2.h: Likewise.
* grub-core/lib/xzembed/xz_private.h: Likewise.
* grub-core/lib/xzembed/xz_stream.h: Likewise.
* include/grub/file.h (grub_file_filter_id): New compression filter
GRUB_FILE_FILTER_XZIO.
2010-09-05 Vladimir Serbinenko <phcoder@gmail.com>
* include/grub/file.h (GRUB_FILE_SIZE_UNKNOWN): New definition.

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@ -1389,6 +1389,15 @@ module = {
common = tests/test_blockarg.c;
};
module = {
name = xzio;
common = io/xzio.c;
common = lib/xzembed/xz_dec_bcj.c;
common = lib/xzembed/xz_dec_lzma2.c;
common = lib/xzembed/xz_dec_stream.c;
cppflags = '-I$(srcdir)/lib/posix_wrap -I$(srcdir)/lib/xzembed';
};
module = {
name = testload;
common = commands/testload.c;

353
grub-core/io/xzio.c Normal file
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@ -0,0 +1,353 @@
/* xzio.c - decompression support for xz */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2010 Free Software Foundation, Inc.
*
* GRUB is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* GRUB is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
#include <grub/err.h>
#include <grub/mm.h>
#include <grub/misc.h>
#include <grub/file.h>
#include <grub/fs.h>
#include <grub/dl.h>
#include "xz.h"
#include "xz_stream.h"
#define XZBUFSIZ 0x2000
#define VLI_MAX_DIGITS 9
#define XZ_STREAM_FOOTER_SIZE 12
struct grub_xzio
{
grub_file_t file;
struct xz_buf buf;
struct xz_dec *dec;
grub_uint8_t inbuf[XZBUFSIZ];
grub_uint8_t outbuf[XZBUFSIZ];
grub_off_t saved_offset;
};
typedef struct grub_xzio *grub_xzio_t;
static struct grub_fs grub_xzio_fs;
static grub_size_t
decode_vli (const grub_uint8_t buf[], grub_size_t size_max,
grub_uint64_t * num)
{
if (size_max == 0)
return 0;
if (size_max > VLI_MAX_DIGITS)
size_max = VLI_MAX_DIGITS;
*num = buf[0] & 0x7F;
grub_size_t i = 0;
while (buf[i++] & 0x80)
{
if (i >= size_max || buf[i] == 0x00)
return 0;
*num |= (uint64_t) (buf[i] & 0x7F) << (i * 7);
}
return i;
}
static grub_ssize_t
read_vli (grub_file_t file, grub_uint64_t * num)
{
grub_uint8_t buf[VLI_MAX_DIGITS];
grub_ssize_t read;
grub_size_t dec;
read = grub_file_read (file, buf, VLI_MAX_DIGITS);
if (read < 0)
return -1;
dec = decode_vli (buf, read, num);
grub_file_seek (file, file->offset - (read - dec));
return dec;
}
/* Function xz_dec_run() should consume header and ask for more (XZ_OK)
* else file is corrupted (or options not supported) or not xz. */
static int
test_header (grub_file_t file)
{
grub_xzio_t xzio = file->data;
xzio->buf.in_size = grub_file_read (xzio->file, xzio->inbuf,
STREAM_HEADER_SIZE);
if (xzio->buf.in_size != STREAM_HEADER_SIZE)
{
grub_error (GRUB_ERR_BAD_FILE_TYPE, "no xz magic found");
return 0;
}
enum xz_ret ret = xz_dec_run (xzio->dec, &xzio->buf);
if (ret == XZ_FORMAT_ERROR)
{
grub_error (GRUB_ERR_BAD_FILE_TYPE, "no xz magic found");
return 0;
}
if (ret != XZ_OK)
{
grub_error (GRUB_ERR_BAD_COMPRESSED_DATA, "not supported xz options");
return 0;
}
return 1;
}
/* Try to find out size of uncompressed data,
* also do some footer sanity checks. */
static int
test_footer (grub_file_t file)
{
grub_xzio_t xzio = file->data;
grub_uint8_t footer[FOOTER_MAGIC_SIZE];
grub_uint32_t backsize;
grub_uint8_t imarker;
grub_uint64_t uncompressed_size_total = 0;
grub_uint64_t uncompressed_size;
grub_uint64_t records;
grub_file_seek (xzio->file, xzio->file->size - FOOTER_MAGIC_SIZE);
if (grub_file_read (xzio->file, footer, FOOTER_MAGIC_SIZE) !=
FOOTER_MAGIC_SIZE
|| grub_memcmp (footer, FOOTER_MAGIC, FOOTER_MAGIC_SIZE) != 0)
goto ERROR;
grub_file_seek (xzio->file, xzio->file->size - 8);
if (grub_file_read (xzio->file, &backsize, sizeof (backsize))
!= sizeof (backsize))
goto ERROR;
/* Calculate real backward size. */
backsize = (grub_le_to_cpu32 (backsize) + 1) * 4;
/* Set file to the beginning of stream index. */
grub_file_seek (xzio->file,
xzio->file->size - XZ_STREAM_FOOTER_SIZE - backsize);
/* Test index marker. */
if (grub_file_read (xzio->file, &imarker, sizeof (imarker)) !=
sizeof (imarker) && imarker != 0x00)
goto ERROR;
if (read_vli (xzio->file, &records) <= 0)
goto ERROR;
for (; records != 0; records--)
{
if (read_vli (xzio->file, &uncompressed_size) <= 0) /* Ignore unpadded. */
goto ERROR;
if (read_vli (xzio->file, &uncompressed_size) <= 0) /* Uncompressed. */
goto ERROR;
uncompressed_size_total += uncompressed_size;
}
file->size = uncompressed_size_total;
grub_file_seek (xzio->file, STREAM_HEADER_SIZE);
return 1;
ERROR:
grub_error (GRUB_ERR_BAD_COMPRESSED_DATA, "bad footer magic");
return 0;
}
static grub_file_t
grub_xzio_open (grub_file_t io)
{
grub_file_t file;
grub_xzio_t xzio;
file = (grub_file_t) grub_zalloc (sizeof (*file));
if (!file)
return 0;
xzio = grub_zalloc (sizeof (*xzio));
if (!xzio)
{
grub_free (file);
return 0;
}
xzio->file = io;
xzio->saved_offset = 0;
file->device = io->device;
file->offset = 0;
file->data = xzio;
file->read_hook = 0;
file->fs = &grub_xzio_fs;
file->size = GRUB_FILE_SIZE_UNKNOWN;
file->not_easly_seekable = 1;
if (grub_file_tell (xzio->file) != 0)
grub_file_seek (xzio->file, 0);
/* Allocated 64KiB for dictionary.
* Decoder will relocate if bigger is needed. */
xzio->dec = xz_dec_init (1 << 16);
if (!xzio->dec)
{
grub_free (file);
grub_free (xzio);
return 0;
}
xzio->buf.in = xzio->inbuf;
xzio->buf.in_pos = 0;
xzio->buf.in_size = 0;
xzio->buf.out = xzio->outbuf;
xzio->buf.out_pos = 0;
xzio->buf.out_size = XZBUFSIZ;
if (!test_header (file) || !(grub_file_seekable (io) && test_footer (file)))
{
grub_errno = GRUB_ERR_NONE;
grub_file_seek (io, 0);
xz_dec_end (xzio->dec);
grub_free (xzio);
grub_free (file);
return io;
}
return file;
}
static grub_ssize_t
grub_xzio_read (grub_file_t file, char *buf, grub_size_t len)
{
grub_ssize_t ret = 0;
grub_ssize_t readret;
enum xz_ret xzret;
grub_xzio_t xzio = file->data;
grub_off_t current_offset;
/* If seek backward need to reset decoder and start from beginning of file.
TODO Possible improvement by jumping blocks. */
if (file->offset < xzio->saved_offset)
{
xz_dec_reset (xzio->dec);
xzio->saved_offset = 0;
xzio->buf.out_pos = 0;
xzio->buf.in_pos = 0;
xzio->buf.in_size = 0;
grub_file_seek (xzio->file, 0);
}
current_offset = xzio->saved_offset;
while (len > 0)
{
xzio->buf.out_size = grub_min (file->offset + ret + len - current_offset,
XZBUFSIZ);
/* Feed input. */
if (xzio->buf.in_pos == xzio->buf.in_size)
{
readret = grub_file_read (xzio->file, xzio->inbuf, XZBUFSIZ);
if (readret < 0)
return -1;
xzio->buf.in_size = readret;
xzio->buf.in_pos = 0;
}
xzret = xz_dec_run (xzio->dec, &xzio->buf);
switch (xzret)
{
case XZ_MEMLIMIT_ERROR:
case XZ_FORMAT_ERROR:
case XZ_OPTIONS_ERROR:
case XZ_DATA_ERROR:
case XZ_BUF_ERROR:
grub_error (GRUB_ERR_BAD_COMPRESSED_DATA,
"file corrupted or unsupported block options");
return -1;
default:
break;
}
{
grub_off_t new_offset = current_offset + xzio->buf.out_pos;
if (file->offset <= new_offset)
/* Store first chunk of data in buffer. */
{
grub_size_t delta = new_offset - (file->offset + ret);
grub_memmove (buf, xzio->buf.out + (xzio->buf.out_pos - delta),
delta);
len -= delta;
buf += delta;
ret += delta;
}
current_offset = new_offset;
}
xzio->buf.out_pos = 0;
if (xzret == XZ_STREAM_END) /* Stream end, EOF. */
break;
}
if (ret >= 0)
xzio->saved_offset = file->offset + ret;
return ret;
}
/* Release everything, including the underlying file object. */
static grub_err_t
grub_xzio_close (grub_file_t file)
{
grub_xzio_t xzio = file->data;
xz_dec_end (xzio->dec);
grub_file_close (xzio->file);
grub_free (xzio);
/* Device must not be closed twice. */
file->device = 0;
return grub_errno;
}
static struct grub_fs grub_xzio_fs = {
.name = "xzio",
.dir = 0,
.open = 0,
.read = grub_xzio_read,
.close = grub_xzio_close,
.label = 0,
.next = 0
};
GRUB_MOD_INIT (xzio)
{
grub_file_filter_register (GRUB_FILE_FILTER_XZIO, grub_xzio_open);
}
GRUB_MOD_FINI (xzio)
{
grub_file_filter_unregister (GRUB_FILE_FILTER_XZIO);
}

180
grub-core/lib/xzembed/xz.h Normal file
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@ -0,0 +1,180 @@
/* xz.h - XZ decompressor */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2010 Free Software Foundation, Inc.
*
* GRUB is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* GRUB is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
/*
* This file is based on code from XZ embedded project
* http://tukaani.org/xz/embedded.html
*/
#ifndef XZ_H
#define XZ_H
#include <stdint.h>
/**
* enum xz_ret - Return codes
* @XZ_OK: Everything is OK so far. More input or more output
* space is required to continue.
* @XZ_STREAM_END: Operation finished successfully.
* @XZ_MEMLIMIT_ERROR: Not enough memory was preallocated at decoder
* initialization time.
* @XZ_FORMAT_ERROR: File format was not recognized (wrong magic bytes).
* @XZ_OPTIONS_ERROR: This implementation doesn't support the requested
* compression options. In the decoder this means that
* the header CRC32 matches, but the header itself
* specifies something that we don't support.
* @XZ_DATA_ERROR: Compressed data is corrupt.
* @XZ_BUF_ERROR: Cannot make any progress. Details are slightly
* different between multi-call and single-call mode;
* more information below.
*
* In multi-call mode, XZ_BUF_ERROR is returned when two consecutive calls
* to XZ code cannot consume any input and cannot produce any new output.
* This happens when there is no new input available, or the output buffer
* is full while at least one output byte is still pending. Assuming your
* code is not buggy, you can get this error only when decoding a compressed
* stream that is truncated or otherwise corrupt.
*
* In single-call mode, XZ_BUF_ERROR is returned only when the output buffer
* is too small, or the compressed input is corrupt in a way that makes the
* decoder produce more output than the caller expected. When it is
* (relatively) clear that the compressed input is truncated, XZ_DATA_ERROR
* is used instead of XZ_BUF_ERROR.
*/
enum xz_ret {
XZ_OK,
XZ_STREAM_END,
XZ_MEMLIMIT_ERROR,
XZ_FORMAT_ERROR,
XZ_OPTIONS_ERROR,
XZ_DATA_ERROR,
XZ_BUF_ERROR
};
/**
* struct xz_buf - Passing input and output buffers to XZ code
* @in: Beginning of the input buffer. This may be NULL if and only
* if in_pos is equal to in_size.
* @in_pos: Current position in the input buffer. This must not exceed
* in_size.
* @in_size: Size of the input buffer
* @out: Beginning of the output buffer. This may be NULL if and only
* if out_pos is equal to out_size.
* @out_pos: Current position in the output buffer. This must not exceed
* out_size.
* @out_size: Size of the output buffer
*
* Only the contents of the output buffer from out[out_pos] onward, and
* the variables in_pos and out_pos are modified by the XZ code.
*/
struct xz_buf {
const uint8_t *in;
size_t in_pos;
size_t in_size;
uint8_t *out;
size_t out_pos;
size_t out_size;
};
/**
* struct xz_dec - Opaque type to hold the XZ decoder state
*/
struct xz_dec;
/**
* xz_dec_init() - Allocate and initialize a XZ decoder state
* @dict_max: Maximum size of the LZMA2 dictionary (history buffer) for
* multi-call decoding, or special value of zero to indicate
* single-call decoding mode.
*
* If dict_max > 0, the decoder is initialized to work in multi-call mode.
* dict_max number of bytes of memory is preallocated for the LZMA2
* dictionary. This way there is no risk that xz_dec_run() could run out
* of memory, since xz_dec_run() will never allocate any memory. Instead,
* if the preallocated dictionary is too small for decoding the given input
* stream, xz_dec_run() will return XZ_MEMLIMIT_ERROR. Thus, it is important
* to know what kind of data will be decoded to avoid allocating excessive
* amount of memory for the dictionary.
*
* LZMA2 dictionary is always 2^n bytes or 2^n + 2^(n-1) bytes (the latter
* sizes are less common in practice). In the kernel, dictionary sizes of
* 64 KiB, 128 KiB, 256 KiB, 512 KiB, and 1 MiB are probably the only
* reasonable values.
*
* If dict_max == 0, the decoder is initialized to work in single-call mode.
* In single-call mode, xz_dec_run() decodes the whole stream at once. The
* caller must provide enough output space or the decoding will fail. The
* output space is used as the dictionary buffer, which is why there is
* no need to allocate the dictionary as part of the decoder's internal
* state.
*
* Because the output buffer is used as the workspace, streams encoded using
* a big dictionary are not a problem in single-call. It is enough that the
* output buffer is is big enough to hold the actual uncompressed data; it
* can be smaller than the dictionary size stored in the stream headers.
*
* On success, xz_dec_init() returns a pointer to struct xz_dec, which is
* ready to be used with xz_dec_run(). On error, xz_dec_init() returns NULL.
*/
struct xz_dec * xz_dec_init(uint32_t dict_max);
/**
* xz_dec_run() - Run the XZ decoder
* @s: Decoder state allocated using xz_dec_init()
* @b: Input and output buffers
*
* In multi-call mode, this function may return any of the values listed in
* enum xz_ret.
*
* In single-call mode, this function never returns XZ_OK. If an error occurs
* in single-call mode (return value is not XZ_STREAM_END), b->in_pos and
* b->out_pos are not modified, and the contents of the output buffer from
* b->out[b->out_pos] onward are undefined.
*
* NOTE: In single-call mode, the contents of the output buffer are undefined
* also after XZ_BUF_ERROR. This is because with some filter chains, there
* may be a second pass over the output buffer, and this pass cannot be
* properly done if the output buffer is truncated. Thus, you cannot give
* the single-call decoder a too small buffer and then expect to get that
* amount valid data from the beginning of the stream. You must use the
* multi-call decoder if you don't want to uncompress the whole stream.
*/
enum xz_ret xz_dec_run(struct xz_dec *s, struct xz_buf *b);
/**
* xz_dec_reset() - Reset an already allocated decoder state
* @s: Decoder state allocated using xz_dec_init()
*
* This function can be used to reset the multi-call decoder state without
* freeing and reallocating memory with xz_dec_end() and xz_dec_init().
*
* In single-call mode, xz_dec_reset() is always called in the beginning of
* xz_dec_run(). Thus, explicit call to xz_dec_reset() is useful only in
* multi-call mode.
*/
void xz_dec_reset(struct xz_dec *s);
/**
* xz_dec_end() - Free the memory allocated for the decoder state
* @s: Decoder state allocated using xz_dec_init(). If s is NULL,
* this function does nothing.
*/
void xz_dec_end(struct xz_dec *s);
#endif

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@ -0,0 +1,141 @@
/* xz_config.h - Private includes and definitions for userspace use */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2010 Free Software Foundation, Inc.
*
* GRUB is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* GRUB is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
/*
* This file is based on code from XZ embedded project
* http://tukaani.org/xz/embedded.html
*/
#ifndef XZ_CONFIG_H
#define XZ_CONFIG_H
/* Enable BCJ filter decoders. */
#if defined(__i386__) || defined(__x86_64__)
#define XZ_DEC_X86
#endif
#ifdef __powerpc__
#define XZ_DEC_POWERPC
#endif
#ifdef __ia64__
#define XZ_DEC_IA64
#endif
#ifdef __arm__
#define XZ_DEC_ARM
#endif
#ifdef __thumb__
#define XZ_DEC_ARMTHUMB
#endif
#ifdef __sparc__
#define XZ_DEC_SPARC
#endif
#include "xz.h"
#include <stdlib.h>
#define kmalloc(size, flags) malloc(size)
#define kfree(ptr) free(ptr)
#define vmalloc(size) malloc(size)
#define vfree(ptr) free(ptr)
#define memeq(a, b, size) (memcmp(a, b, size) == 0)
#define memzero(buf, size) memset(buf, 0, size)
#define min(x, y) ((x) < (y) ? (x) : (y))
#define min_t(type, x, y) min(x, y)
/*
* Some functions have been marked with __always_inline to keep the
* performance reasonable even when the compiler is optimizing for
* small code size. You may be able to save a few bytes by #defining
* __always_inline to plain inline, but don't complain if the code
* becomes slow.
*
* NOTE: System headers on GNU/Linux may #define this macro already,
* so if you want to change it, it you need to #undef it first.
*/
#ifndef __always_inline
# ifdef __GNUC__
# define __always_inline \
inline __attribute__((__always_inline__))
# else
# define __always_inline inline
# endif
#endif
/*
* Some functions are marked to never be inlined to reduce stack usage.
* If you don't care about stack usage, you may want to modify this so
* that noinline_for_stack is #defined to be empty even when using GCC.
* Doing so may save a few bytes in binary size.
*/
#ifndef noinline_for_stack
# ifdef __GNUC__
# define noinline_for_stack __attribute__((__noinline__))
# else
# define noinline_for_stack
# endif
#endif
/* Inline functions to access unaligned unsigned 32-bit integers */
static inline uint32_t get_unaligned_le32(const uint8_t *buf)
{
return (uint32_t)buf[0]
| ((uint32_t)buf[1] << 8)
| ((uint32_t)buf[2] << 16)
| ((uint32_t)buf[3] << 24);
}
static inline uint32_t get_unaligned_be32(const uint8_t *buf)
{
return (uint32_t)(buf[0] << 24)
| ((uint32_t)buf[1] << 16)
| ((uint32_t)buf[2] << 8)
| (uint32_t)buf[3];
}
static inline void put_unaligned_le32(uint32_t val, uint8_t *buf)
{
buf[0] = (uint8_t)val;
buf[1] = (uint8_t)(val >> 8);
buf[2] = (uint8_t)(val >> 16);
buf[3] = (uint8_t)(val >> 24);
}
static inline void put_unaligned_be32(uint32_t val, uint8_t *buf)
{
buf[0] = (uint8_t)(val >> 24);
buf[1] = (uint8_t)(val >> 16);
buf[2] = (uint8_t)(val >> 8);
buf[3] = (uint8_t)val;
}
/*
* Use get_unaligned_le32() also for aligned access for simplicity. On
* little endian systems, #define get_le32(ptr) (*(const uint32_t *)(ptr))
* could save a few bytes in code size.
*/
#define get_le32 get_unaligned_le32
#endif

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/* xz_dec_bcj.c - Branch/Call/Jump (BCJ) filter decoders */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2010 Free Software Foundation, Inc.
*
* GRUB is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* GRUB is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
/*
* This file is based on code from XZ embedded project
* http://tukaani.org/xz/embedded.html
*/
#include "xz_private.h"
struct xz_dec_bcj {
/* Type of the BCJ filter being used */
enum {
BCJ_X86 = 4, /* x86 or x86-64 */
BCJ_POWERPC = 5, /* Big endian only */
BCJ_IA64 = 6, /* Big or little endian */
BCJ_ARM = 7, /* Little endian only */
BCJ_ARMTHUMB = 8, /* Little endian only */
BCJ_SPARC = 9 /* Big or little endian */
} type;
/*
* Return value of the next filter in the chain. We need to preserve
* this information across calls, because we must not call the next
* filter anymore once it has returned XZ_STREAM_END.
*/
enum xz_ret ret;
/* True if we are operating in single-call mode. */
bool single_call;
/*
* Absolute position relative to the beginning of the uncompressed
* data (in a single .xz Block). We care only about the lowest 32
* bits so this doesn't need to be uint64_t even with big files.
*/
uint32_t pos;
/* x86 filter state */
uint32_t x86_prev_mask;
/* Temporary space to hold the variables from struct xz_buf */
uint8_t *out;
size_t out_pos;
size_t out_size;
struct {
/* Amount of already filtered data in the beginning of buf */
size_t filtered;
/* Total amount of data currently stored in buf */
size_t size;
/*
* Buffer to hold a mix of filtered and unfiltered data. This
* needs to be big enough to hold Alignment + 2 * Look-ahead:
*
* Type Alignment Look-ahead
* x86 1 4
* PowerPC 4 0
* IA-64 16 0
* ARM 4 0
* ARM-Thumb 2 2
* SPARC 4 0
*/
uint8_t buf[16];
} temp;
};
#ifdef XZ_DEC_X86
/*
* This is macro used to test the most significant byte of a memory address
* in an x86 instruction.
*/
#define bcj_x86_test_msbyte(b) ((b) == 0x00 || (b) == 0xFF)
static noinline_for_stack size_t bcj_x86(
struct xz_dec_bcj *s, uint8_t *buf, size_t size)
{
static const bool mask_to_allowed_status[8]
= { true, true, true, false, true, false, false, false };
static const uint8_t mask_to_bit_num[8] = { 0, 1, 2, 2, 3, 3, 3, 3 };
size_t i;
size_t prev_pos = (size_t)-1;
uint32_t prev_mask = s->x86_prev_mask;
uint32_t src;
uint32_t dest;
uint32_t j;
uint8_t b;
if (size <= 4)
return 0;
size -= 4;
for (i = 0; i < size; ++i) {
if ((buf[i] & 0xFE) != 0xE8)
continue;
prev_pos = i - prev_pos;
if (prev_pos > 3) {
prev_mask = 0;
} else {
prev_mask = (prev_mask << (prev_pos - 1)) & 7;
if (prev_mask != 0) {
b = buf[i + 4 - mask_to_bit_num[prev_mask]];
if (!mask_to_allowed_status[prev_mask]
|| bcj_x86_test_msbyte(b)) {
prev_pos = i;
prev_mask = (prev_mask << 1) | 1;
continue;
}
}
}
prev_pos = i;
if (bcj_x86_test_msbyte(buf[i + 4])) {
src = get_unaligned_le32(buf + i + 1);
while (true) {
dest = src - (s->pos + (uint32_t)i + 5);
if (prev_mask == 0)
break;
j = mask_to_bit_num[prev_mask] * 8;
b = (uint8_t)(dest >> (24 - j));
if (!bcj_x86_test_msbyte(b))
break;
src = dest ^ (((uint32_t)1 << (32 - j)) - 1);
}
dest &= 0x01FFFFFF;
dest |= (uint32_t)0 - (dest & 0x01000000);
put_unaligned_le32(dest, buf + i + 1);
i += 4;
} else {
prev_mask = (prev_mask << 1) | 1;
}
}
prev_pos = i - prev_pos;
s->x86_prev_mask = prev_pos > 3 ? 0 : prev_mask << (prev_pos - 1);
return i;
}
#endif
#ifdef XZ_DEC_POWERPC
static noinline_for_stack size_t bcj_powerpc(
struct xz_dec_bcj *s, uint8_t *buf, size_t size)
{
size_t i;
uint32_t instr;
for (i = 0; i + 4 <= size; i += 4) {
instr = get_unaligned_be32(buf + i);
if ((instr & 0xFC000003) == 0x48000001) {
instr &= 0x03FFFFFC;
instr -= s->pos + (uint32_t)i;
instr &= 0x03FFFFFC;
instr |= 0x48000001;
put_unaligned_be32(instr, buf + i);
}
}
return i;
}
#endif
#ifdef XZ_DEC_IA64
static noinline_for_stack size_t bcj_ia64(
struct xz_dec_bcj *s, uint8_t *buf, size_t size)
{
static const uint8_t branch_table[32] = {
0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0,
4, 4, 6, 6, 0, 0, 7, 7,
4, 4, 0, 0, 4, 4, 0, 0
};
/*
* The local variables take a little bit stack space, but it's less
* than what LZMA2 decoder takes, so it doesn't make sense to reduce
* stack usage here without doing that for the LZMA2 decoder too.
*/
/* Loop counters */
size_t i;
size_t j;
/* Instruction slot (0, 1, or 2) in the 128-bit instruction word */
uint32_t slot;
/* Bitwise offset of the instruction indicated by slot */
uint32_t bit_pos;
/* bit_pos split into byte and bit parts */
uint32_t byte_pos;
uint32_t bit_res;
/* Address part of an instruction */
uint32_t addr;
/* Mask used to detect which instructions to convert */
uint32_t mask;
/* 41-bit instruction stored somewhere in the lowest 48 bits */
uint64_t instr;
/* Instruction normalized with bit_res for easier manipulation */
uint64_t norm;
for (i = 0; i + 16 <= size; i += 16) {
mask = branch_table[buf[i] & 0x1F];
for (slot = 0, bit_pos = 5; slot < 3; ++slot, bit_pos += 41) {
if (((mask >> slot) & 1) == 0)
continue;
byte_pos = bit_pos >> 3;
bit_res = bit_pos & 7;
instr = 0;
for (j = 0; j < 6; ++j)
instr |= (uint64_t)(buf[i + j + byte_pos])
<< (8 * j);
norm = instr >> bit_res;
if (((norm >> 37) & 0x0F) == 0x05
&& ((norm >> 9) & 0x07) == 0) {
addr = (norm >> 13) & 0x0FFFFF;
addr |= ((uint32_t)(norm >> 36) & 1) << 20;
addr <<= 4;
addr -= s->pos + (uint32_t)i;
addr >>= 4;
norm &= ~((uint64_t)0x8FFFFF << 13);
norm |= (uint64_t)(addr & 0x0FFFFF) << 13;
norm |= (uint64_t)(addr & 0x100000)
<< (36 - 20);
instr &= (1 << bit_res) - 1;
instr |= norm << bit_res;
for (j = 0; j < 6; j++)
buf[i + j + byte_pos]
= (uint8_t)(instr >> (8 * j));
}
}
}
return i;
}
#endif
#ifdef XZ_DEC_ARM
static noinline_for_stack size_t bcj_arm(
struct xz_dec_bcj *s, uint8_t *buf, size_t size)
{
size_t i;
uint32_t addr;
for (i = 0; i + 4 <= size; i += 4) {
if (buf[i + 3] == 0xEB) {
addr = (uint32_t)buf[i] | ((uint32_t)buf[i + 1] << 8)
| ((uint32_t)buf[i + 2] << 16);
addr <<= 2;
addr -= s->pos + (uint32_t)i + 8;
addr >>= 2;
buf[i] = (uint8_t)addr;
buf[i + 1] = (uint8_t)(addr >> 8);
buf[i + 2] = (uint8_t)(addr >> 16);
}
}
return i;
}
#endif
#ifdef XZ_DEC_ARMTHUMB
static noinline_for_stack size_t bcj_armthumb(
struct xz_dec_bcj *s, uint8_t *buf, size_t size)
{
size_t i;
uint32_t addr;
for (i = 0; i + 4 <= size; i += 2) {
if ((buf[i + 1] & 0xF8) == 0xF0
&& (buf[i + 3] & 0xF8) == 0xF8) {
addr = (((uint32_t)buf[i + 1] & 0x07) << 19)
| ((uint32_t)buf[i] << 11)
| (((uint32_t)buf[i + 3] & 0x07) << 8)
| (uint32_t)buf[i + 2];
addr <<= 1;
addr -= s->pos + (uint32_t)i + 4;
addr >>= 1;
buf[i + 1] = (uint8_t)(0xF0 | ((addr >> 19) & 0x07));
buf[i] = (uint8_t)(addr >> 11);
buf[i + 3] = (uint8_t)(0xF8 | ((addr >> 8) & 0x07));
buf[i + 2] = (uint8_t)addr;
i += 2;
}
}
return i;
}
#endif
#ifdef XZ_DEC_SPARC
static noinline_for_stack size_t bcj_sparc(
struct xz_dec_bcj *s, uint8_t *buf, size_t size)
{
size_t i;
uint32_t instr;
for (i = 0; i + 4 <= size; i += 4) {
instr = get_unaligned_be32(buf + i);
if ((instr >> 22) == 0x100 || (instr >> 22) == 0x1FF) {
instr <<= 2;
instr -= s->pos + (uint32_t)i;
instr >>= 2;
instr = ((uint32_t)0x40000000 - (instr & 0x400000))
| 0x40000000 | (instr & 0x3FFFFF);
put_unaligned_be32(instr, buf + i);
}
}
return i;
}
#endif
/*
* Apply the selected BCJ filter. Update *pos and s->pos to match the amount
* of data that got filtered.
*
* NOTE: This is implemented as a switch statement to avoid using function
* pointers, which could be problematic in the kernel boot code, which must
* avoid pointers to static data (at least on x86).
*/
static void bcj_apply(struct xz_dec_bcj *s,
uint8_t *buf, size_t *pos, size_t size)
{
size_t filtered;
buf += *pos;
size -= *pos;
switch (s->type) {
#ifdef XZ_DEC_X86
case BCJ_X86:
filtered = bcj_x86(s, buf, size);
break;
#endif
#ifdef XZ_DEC_POWERPC
case BCJ_POWERPC:
filtered = bcj_powerpc(s, buf, size);
break;
#endif
#ifdef XZ_DEC_IA64
case BCJ_IA64:
filtered = bcj_ia64(s, buf, size);
break;
#endif
#ifdef XZ_DEC_ARM
case BCJ_ARM:
filtered = bcj_arm(s, buf, size);
break;
#endif
#ifdef XZ_DEC_ARMTHUMB
case BCJ_ARMTHUMB:
filtered = bcj_armthumb(s, buf, size);
break;
#endif
#ifdef XZ_DEC_SPARC
case BCJ_SPARC:
filtered = bcj_sparc(s, buf, size);
break;
#endif
default:
/* Never reached but silence compiler warnings. */
filtered = 0;
break;
}
*pos += filtered;
s->pos += filtered;
}
/*
* Flush pending filtered data from temp to the output buffer.
* Move the remaining mixture of possibly filtered and unfiltered
* data to the beginning of temp.
*/
static void bcj_flush(struct xz_dec_bcj *s, struct xz_buf *b)
{
size_t copy_size;
copy_size = min_t(size_t, s->temp.filtered, b->out_size - b->out_pos);
memcpy(b->out + b->out_pos, s->temp.buf, copy_size);
b->out_pos += copy_size;
s->temp.filtered -= copy_size;
s->temp.size -= copy_size;
memmove(s->temp.buf, s->temp.buf + copy_size, s->temp.size);
}
/*
* The BCJ filter functions are primitive in sense that they process the
* data in chunks of 1-16 bytes. To hide this issue, this function does
* some buffering.
*/
enum xz_ret xz_dec_bcj_run(struct xz_dec_bcj *s,
struct xz_dec_lzma2 *lzma2, struct xz_buf *b)
{
size_t out_start;
/*
* Flush pending already filtered data to the output buffer. Return
* immediatelly if we couldn't flush everything, or if the next
* filter in the chain had already returned XZ_STREAM_END.
*/
if (s->temp.filtered > 0) {
bcj_flush(s, b);
if (s->temp.filtered > 0)
return XZ_OK;
if (s->ret == XZ_STREAM_END)
return XZ_STREAM_END;
}
/*
* If we have more output space than what is currently pending in
* temp, copy the unfiltered data from temp to the output buffer
* and try to fill the output buffer by decoding more data from the
* next filter in the chain. Apply the BCJ filter on the new data
* in the output buffer. If everything cannot be filtered, copy it
* to temp and rewind the output buffer position accordingly.
*/
if (s->temp.size < b->out_size - b->out_pos) {
out_start = b->out_pos;
memcpy(b->out + b->out_pos, s->temp.buf, s->temp.size);
b->out_pos += s->temp.size;
s->ret = xz_dec_lzma2_run(lzma2, b);
if (s->ret != XZ_STREAM_END
&& (s->ret != XZ_OK || s->single_call))
return s->ret;
bcj_apply(s, b->out, &out_start, b->out_pos);
/*
* As an exception, if the next filter returned XZ_STREAM_END,
* we can do that too, since the last few bytes that remain
* unfiltered are meant to remain unfiltered.
*/
if (s->ret == XZ_STREAM_END)
return XZ_STREAM_END;
s->temp.size = b->out_pos - out_start;
b->out_pos -= s->temp.size;
memcpy(s->temp.buf, b->out + b->out_pos, s->temp.size);
}
/*
* If we have unfiltered data in temp, try to fill by decoding more
* data from the next filter. Apply the BCJ filter on temp. Then we
* hopefully can fill the actual output buffer by copying filtered
* data from temp. A mix of filtered and unfiltered data may be left
* in temp; it will be taken care on the next call to this function.
*/
if (s->temp.size > 0) {
/* Make b->out{,_pos,_size} temporarily point to s->temp. */
s->out = b->out;
s->out_pos = b->out_pos;
s->out_size = b->out_size;
b->out = s->temp.buf;
b->out_pos = s->temp.size;
b->out_size = sizeof(s->temp.buf);
s->ret = xz_dec_lzma2_run(lzma2, b);
s->temp.size = b->out_pos;
b->out = s->out;
b->out_pos = s->out_pos;
b->out_size = s->out_size;
if (s->ret != XZ_OK && s->ret != XZ_STREAM_END)
return s->ret;
bcj_apply(s, s->temp.buf, &s->temp.filtered, s->temp.size);
/*
* If the next filter returned XZ_STREAM_END, we mark that
* everything is filtered, since the last unfiltered bytes
* of the stream are meant to be left as is.
*/
if (s->ret == XZ_STREAM_END)
s->temp.filtered = s->temp.size;
bcj_flush(s, b);
if (s->temp.filtered > 0)
return XZ_OK;
}
return s->ret;
}
struct xz_dec_bcj * xz_dec_bcj_create(bool single_call)
{
struct xz_dec_bcj *s = kmalloc(sizeof(*s), GFP_KERNEL);
if (s != NULL)
s->single_call = single_call;
return s;
}
enum xz_ret xz_dec_bcj_reset(
struct xz_dec_bcj *s, uint8_t id)
{
switch (id) {
#ifdef XZ_DEC_X86
case BCJ_X86:
#endif
#ifdef XZ_DEC_POWERPC
case BCJ_POWERPC:
#endif
#ifdef XZ_DEC_IA64
case BCJ_IA64:
#endif
#ifdef XZ_DEC_ARM
case BCJ_ARM:
#endif
#ifdef XZ_DEC_ARMTHUMB
case BCJ_ARMTHUMB:
#endif
#ifdef XZ_DEC_SPARC
case BCJ_SPARC:
#endif
break;
default:
/* Unsupported Filter ID */
return XZ_OPTIONS_ERROR;
}
s->type = id;
s->ret = XZ_OK;
s->pos = 0;
s->x86_prev_mask = 0;
s->temp.filtered = 0;
s->temp.size = 0;
return XZ_OK;
}

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@ -0,0 +1,854 @@
/* xz_dec_stream.c - .xz Stream decoder */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2010 Free Software Foundation, Inc.
*
* GRUB is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* GRUB is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
/*
* This file is based on code from XZ embedded project
* http://tukaani.org/xz/embedded.html
*/
#include "xz_config.h"
#include "xz_private.h"
#include "xz_stream.h"
#include <grub/crypto.h>
/* Hash used to validate the Index field */
struct xz_dec_hash {
vli_type unpadded;
vli_type uncompressed;
uint8_t *crc32_context;
};
struct xz_dec {
/* Position in dec_main() */
enum {
SEQ_STREAM_HEADER,
SEQ_BLOCK_START,
SEQ_BLOCK_HEADER,
SEQ_BLOCK_UNCOMPRESS,
SEQ_BLOCK_PADDING,
SEQ_BLOCK_CHECK,
SEQ_INDEX,
SEQ_INDEX_PADDING,
SEQ_INDEX_CRC32,
SEQ_STREAM_FOOTER
} sequence;
/* Position in variable-length integers and Check fields */
uint32_t pos;
/* Variable-length integer decoded by dec_vli() */
vli_type vli;
/* Saved in_pos and out_pos */
size_t in_start;
size_t out_start;
/* CRC32 value in Block or Index */
uint32_t crc32_temp; /* need for crc32_validate*/
uint8_t *crc32_context;
/* True if CRC32 is calculated from uncompressed data */
bool has_crc32;
/* True if we are operating in single-call mode. */
bool single_call;
/*
* True if the next call to xz_dec_run() is allowed to return
* XZ_BUF_ERROR.
*/
bool allow_buf_error;
/* Information stored in Block Header */
struct {
/*
* Value stored in the Compressed Size field, or
* VLI_UNKNOWN if Compressed Size is not present.
*/
vli_type compressed;
/*
* Value stored in the Uncompressed Size field, or
* VLI_UNKNOWN if Uncompressed Size is not present.
*/
vli_type uncompressed;
/* Size of the Block Header field */
uint32_t size;
} block_header;
/* Information collected when decoding Blocks */
struct {
/* Observed compressed size of the current Block */
vli_type compressed;
/* Observed uncompressed size of the current Block */
vli_type uncompressed;
/* Number of Blocks decoded so far */
vli_type count;
/*
* Hash calculated from the Block sizes. This is used to
* validate the Index field.
*/
struct xz_dec_hash hash;
} block;
/* Variables needed when verifying the Index field */
struct {
/* Position in dec_index() */
enum {
SEQ_INDEX_COUNT,
SEQ_INDEX_UNPADDED,
SEQ_INDEX_UNCOMPRESSED
} sequence;
/* Size of the Index in bytes */
vli_type size;
/* Number of Records (matches block.count in valid files) */
vli_type count;
/*
* Hash calculated from the Records (matches block.hash in
* valid files).
*/
struct xz_dec_hash hash;
} index;
/*
* Temporary buffer needed to hold Stream Header, Block Header,
* and Stream Footer. The Block Header is the biggest (1 KiB)
* so we reserve space according to that. buf[] has to be aligned
* to a multiple of four bytes; the size_t variables before it
* should guarantee this.
*/
struct {
size_t pos;
size_t size;
uint8_t buf[1024];
} temp;
struct xz_dec_lzma2 *lzma2;
#ifdef XZ_DEC_BCJ
struct xz_dec_bcj *bcj;
bool bcj_active;
#endif
};
/*
* Fill s->temp by copying data starting from b->in[b->in_pos]. Caller
* must have set s->temp.pos to indicate how much data we are supposed
* to copy into s->temp.buf. Return true once s->temp.pos has reached
* s->temp.size.
*/
static bool fill_temp(struct xz_dec *s, struct xz_buf *b)
{
size_t copy_size = min_t(size_t,
b->in_size - b->in_pos, s->temp.size - s->temp.pos);
memcpy(s->temp.buf + s->temp.pos, b->in + b->in_pos, copy_size);
b->in_pos += copy_size;
s->temp.pos += copy_size;
if (s->temp.pos == s->temp.size) {
s->temp.pos = 0;
return true;
}
return false;
}
/* Decode a variable-length integer (little-endian base-128 encoding) */
static enum xz_ret dec_vli(struct xz_dec *s,
const uint8_t *in, size_t *in_pos, size_t in_size)
{
uint8_t byte;
if (s->pos == 0)
s->vli = 0;
while (*in_pos < in_size) {
byte = in[*in_pos];
++*in_pos;
s->vli |= (vli_type)(byte & 0x7F) << s->pos;
if ((byte & 0x80) == 0) {
/* Don't allow non-minimal encodings. */
if (byte == 0 && s->pos != 0)
return XZ_DATA_ERROR;
s->pos = 0;
return XZ_STREAM_END;
}
s->pos += 7;
if (s->pos == 7 * VLI_BYTES_MAX)
return XZ_DATA_ERROR;
}
return XZ_OK;
}
/*
* Decode the Compressed Data field from a Block. Update and validate
* the observed compressed and uncompressed sizes of the Block so that
* they don't exceed the values possibly stored in the Block Header
* (validation assumes that no integer overflow occurs, since vli_type
* is normally uint64_t). Update the CRC32 if presence of the CRC32
* field was indicated in Stream Header.
*
* Once the decoding is finished, validate that the observed sizes match
* the sizes possibly stored in the Block Header. Update the hash and
* Block count, which are later used to validate the Index field.
*/
static enum xz_ret dec_block(struct xz_dec *s, struct xz_buf *b)
{
enum xz_ret ret;
s->in_start = b->in_pos;
s->out_start = b->out_pos;
#ifdef XZ_DEC_BCJ
if (s->bcj_active)
ret = xz_dec_bcj_run(s->bcj, s->lzma2, b);
else
#endif
ret = xz_dec_lzma2_run(s->lzma2, b);
s->block.compressed += b->in_pos - s->in_start;
s->block.uncompressed += b->out_pos - s->out_start;
/*
* There is no need to separately check for VLI_UNKNOWN, since
* the observed sizes are always smaller than VLI_UNKNOWN.
*/
if (s->block.compressed > s->block_header.compressed
|| s->block.uncompressed
> s->block_header.uncompressed)
return XZ_DATA_ERROR;
if (s->has_crc32)
GRUB_MD_CRC32->write(s->crc32_context,b->out + s->out_start,
b->out_pos - s->out_start);
if (ret == XZ_STREAM_END) {
if (s->block_header.compressed != VLI_UNKNOWN
&& s->block_header.compressed
!= s->block.compressed)
return XZ_DATA_ERROR;
if (s->block_header.uncompressed != VLI_UNKNOWN
&& s->block_header.uncompressed
!= s->block.uncompressed)
return XZ_DATA_ERROR;
s->block.hash.unpadded += s->block_header.size
+ s->block.compressed;
if (s->has_crc32)
s->block.hash.unpadded += 4;
s->block.hash.uncompressed += s->block.uncompressed;
GRUB_MD_CRC32->write(s->block.hash.crc32_context,
(const uint8_t *)&s->block.hash, sizeof(s->block.hash));
++s->block.count;
}
return ret;
}
/* Update the Index size and the CRC32 value. */
static void index_update(struct xz_dec *s, const struct xz_buf *b)
{
size_t in_used = b->in_pos - s->in_start;
s->index.size += in_used;
GRUB_MD_CRC32->write(s->crc32_context,b->in + s->in_start, in_used);
}
/*
* Decode the Number of Records, Unpadded Size, and Uncompressed Size
* fields from the Index field. That is, Index Padding and CRC32 are not
* decoded by this function.
*
* This can return XZ_OK (more input needed), XZ_STREAM_END (everything
* successfully decoded), or XZ_DATA_ERROR (input is corrupt).
*/
static enum xz_ret dec_index(struct xz_dec *s, struct xz_buf *b)
{
enum xz_ret ret;
do {
ret = dec_vli(s, b->in, &b->in_pos, b->in_size);
if (ret != XZ_STREAM_END) {
index_update(s, b);
return ret;
}
switch (s->index.sequence) {
case SEQ_INDEX_COUNT:
s->index.count = s->vli;
/*
* Validate that the Number of Records field
* indicates the same number of Records as
* there were Blocks in the Stream.
*/
if (s->index.count != s->block.count)
return XZ_DATA_ERROR;
s->index.sequence = SEQ_INDEX_UNPADDED;
break;
case SEQ_INDEX_UNPADDED:
s->index.hash.unpadded += s->vli;
s->index.sequence = SEQ_INDEX_UNCOMPRESSED;
break;
case SEQ_INDEX_UNCOMPRESSED:
s->index.hash.uncompressed += s->vli;
GRUB_MD_CRC32->write(s->index.hash.crc32_context,
(const uint8_t *)&s->index.hash,
sizeof(s->index.hash));
--s->index.count;
s->index.sequence = SEQ_INDEX_UNPADDED;
break;
}
} while (s->index.count > 0);
return XZ_STREAM_END;
}
/*
* Validate that the next four input bytes match the value of s->crc32.
* s->pos must be zero when starting to validate the first byte.
*/
static enum xz_ret crc32_validate(struct xz_dec *s, struct xz_buf *b)
{
if(s->crc32_temp == 0)
{
GRUB_MD_CRC32->final(s->crc32_context);
s->crc32_temp = get_unaligned_be32(GRUB_MD_CRC32->read(s->crc32_context));
}
do {
if (b->in_pos == b->in_size)
return XZ_OK;
if (((s->crc32_temp >> s->pos) & 0xFF) != b->in[b->in_pos++])
return XZ_DATA_ERROR;
s->pos += 8;
} while (s->pos < 32);
GRUB_MD_CRC32->init(s->crc32_context);
s->crc32_temp = 0;
s->pos = 0;
return XZ_STREAM_END;
}
/* Decode the Stream Header field (the first 12 bytes of the .xz Stream). */
static enum xz_ret dec_stream_header(struct xz_dec *s)
{
if (! memeq(s->temp.buf, HEADER_MAGIC, HEADER_MAGIC_SIZE))
return XZ_FORMAT_ERROR;
uint8_t crc32_context[GRUB_MD_CRC32->contextsize];
GRUB_MD_CRC32->init(crc32_context);
GRUB_MD_CRC32->write(crc32_context,s->temp.buf + HEADER_MAGIC_SIZE, 2);
GRUB_MD_CRC32->final(crc32_context);
uint32_t resultcrc = get_unaligned_be32(GRUB_MD_CRC32->read(crc32_context));
uint32_t readcrc = get_unaligned_le32(s->temp.buf + HEADER_MAGIC_SIZE + 2);
if(resultcrc != readcrc)
return XZ_DATA_ERROR;
/*
* Decode the Stream Flags field. Of integrity checks, we support
* only none (Check ID = 0) and CRC32 (Check ID = 1).
*/
if (s->temp.buf[HEADER_MAGIC_SIZE] != 0
|| s->temp.buf[HEADER_MAGIC_SIZE + 1] > 1)
return XZ_OPTIONS_ERROR;
s->has_crc32 = s->temp.buf[HEADER_MAGIC_SIZE + 1];
return XZ_OK;
}
/* Decode the Stream Footer field (the last 12 bytes of the .xz Stream) */
static enum xz_ret dec_stream_footer(struct xz_dec *s)
{
if (! memeq(s->temp.buf + 10, FOOTER_MAGIC, FOOTER_MAGIC_SIZE))
return XZ_DATA_ERROR;
uint8_t crc32_context[GRUB_MD_CRC32->contextsize];
GRUB_MD_CRC32->init(crc32_context);
GRUB_MD_CRC32->write(crc32_context, s->temp.buf + 4, 6);
GRUB_MD_CRC32->final(crc32_context);
uint32_t resultcrc = get_unaligned_be32(GRUB_MD_CRC32->read(crc32_context));
uint32_t readcrc = get_unaligned_le32(s->temp.buf);
if(resultcrc != readcrc)
return XZ_DATA_ERROR;
/*
* Validate Backward Size. Note that we never added the size of the
* Index CRC32 field to s->index.size, thus we use s->index.size / 4
* instead of s->index.size / 4 - 1.
*/
if ((s->index.size >> 2) != get_le32(s->temp.buf + 4))
return XZ_DATA_ERROR;
if (s->temp.buf[8] != 0 || s->temp.buf[9] != s->has_crc32)
return XZ_DATA_ERROR;
/*
* Use XZ_STREAM_END instead of XZ_OK to be more convenient
* for the caller.
*/
return XZ_STREAM_END;
}
/* Decode the Block Header and initialize the filter chain. */
static enum xz_ret dec_block_header(struct xz_dec *s)
{
enum xz_ret ret;
/*
* Validate the CRC32. We know that the temp buffer is at least
* eight bytes so this is safe.
*/
s->temp.size -= 4;
uint8_t crc32_context[GRUB_MD_CRC32->contextsize];
GRUB_MD_CRC32->init(crc32_context);
GRUB_MD_CRC32->write(crc32_context, s->temp.buf, s->temp.size);
GRUB_MD_CRC32->final(crc32_context);
uint32_t resultcrc = get_unaligned_be32(GRUB_MD_CRC32->read(crc32_context));
uint32_t readcrc = get_unaligned_le32(s->temp.buf + s->temp.size);
if (resultcrc != readcrc)
return XZ_DATA_ERROR;
s->temp.pos = 2;
/*
* Catch unsupported Block Flags. We support only one or two filters
* in the chain, so we catch that with the same test.
*/
#ifdef XZ_DEC_BCJ
if (s->temp.buf[1] & 0x3E)
#else
if (s->temp.buf[1] & 0x3F)
#endif
return XZ_OPTIONS_ERROR;
/* Compressed Size */
if (s->temp.buf[1] & 0x40) {
if (dec_vli(s, s->temp.buf, &s->temp.pos, s->temp.size)
!= XZ_STREAM_END)
return XZ_DATA_ERROR;
s->block_header.compressed = s->vli;
} else {
s->block_header.compressed = VLI_UNKNOWN;
}
/* Uncompressed Size */
if (s->temp.buf[1] & 0x80) {
if (dec_vli(s, s->temp.buf, &s->temp.pos, s->temp.size)
!= XZ_STREAM_END)
return XZ_DATA_ERROR;
s->block_header.uncompressed = s->vli;
} else {
s->block_header.uncompressed = VLI_UNKNOWN;
}
#ifdef XZ_DEC_BCJ
/* If there are two filters, the first one must be a BCJ filter. */
s->bcj_active = s->temp.buf[1] & 0x01;
if (s->bcj_active) {
if (s->temp.size - s->temp.pos < 2)
return XZ_OPTIONS_ERROR;
ret = xz_dec_bcj_reset(s->bcj, s->temp.buf[s->temp.pos++]);
if (ret != XZ_OK)
return ret;
/*
* We don't support custom start offset,
* so Size of Properties must be zero.
*/
if (s->temp.buf[s->temp.pos++] != 0x00)
return XZ_OPTIONS_ERROR;
}
#endif
/* Valid Filter Flags always take at least two bytes. */
if (s->temp.size - s->temp.pos < 2)
return XZ_DATA_ERROR;
/* Filter ID = LZMA2 */
if (s->temp.buf[s->temp.pos++] != 0x21)
return XZ_OPTIONS_ERROR;
/* Size of Properties = 1-byte Filter Properties */
if (s->temp.buf[s->temp.pos++] != 0x01)
return XZ_OPTIONS_ERROR;
/* Filter Properties contains LZMA2 dictionary size. */
if (s->temp.size - s->temp.pos < 1)
return XZ_DATA_ERROR;
ret = xz_dec_lzma2_reset(s->lzma2, s->temp.buf[s->temp.pos++]);
if (ret != XZ_OK)
return ret;
/* The rest must be Header Padding. */
while (s->temp.pos < s->temp.size)
if (s->temp.buf[s->temp.pos++] != 0x00)
return XZ_OPTIONS_ERROR;
s->temp.pos = 0;
s->block.compressed = 0;
s->block.uncompressed = 0;
return XZ_OK;
}
static enum xz_ret dec_main(struct xz_dec *s, struct xz_buf *b)
{
enum xz_ret ret;
/*
* Store the start position for the case when we are in the middle
* of the Index field.
*/
s->in_start = b->in_pos;
while (true) {
switch (s->sequence) {
case SEQ_STREAM_HEADER:
/*
* Stream Header is copied to s->temp, and then
* decoded from there. This way if the caller
* gives us only little input at a time, we can
* still keep the Stream Header decoding code
* simple. Similar approach is used in many places
* in this file.
*/
if (!fill_temp(s, b))
return XZ_OK;
ret = dec_stream_header(s);
if (ret != XZ_OK)
return ret;
s->sequence = SEQ_BLOCK_START;
case SEQ_BLOCK_START:
/* We need one byte of input to continue. */
if (b->in_pos == b->in_size)
return XZ_OK;
/* See if this is the beginning of the Index field. */
if (b->in[b->in_pos] == 0) {
s->in_start = b->in_pos++;
s->sequence = SEQ_INDEX;
break;
}
/*
* Calculate the size of the Block Header and
* prepare to decode it.
*/
s->block_header.size
= ((uint32_t)b->in[b->in_pos] + 1) * 4;
s->temp.size = s->block_header.size;
s->temp.pos = 0;
s->sequence = SEQ_BLOCK_HEADER;
case SEQ_BLOCK_HEADER:
if (!fill_temp(s, b))
return XZ_OK;
ret = dec_block_header(s);
if (ret != XZ_OK)
return ret;
s->sequence = SEQ_BLOCK_UNCOMPRESS;
case SEQ_BLOCK_UNCOMPRESS:
ret = dec_block(s, b);
if (ret != XZ_STREAM_END)
return ret;
s->sequence = SEQ_BLOCK_PADDING;
case SEQ_BLOCK_PADDING:
/*
* Size of Compressed Data + Block Padding
* must be a multiple of four. We don't need
* s->block.compressed for anything else
* anymore, so we use it here to test the size
* of the Block Padding field.
*/
while (s->block.compressed & 3) {
if (b->in_pos == b->in_size)
return XZ_OK;
if (b->in[b->in_pos++] != 0)
return XZ_DATA_ERROR;
++s->block.compressed;
}
s->sequence = SEQ_BLOCK_CHECK;
case SEQ_BLOCK_CHECK:
if (s->has_crc32) {
ret = crc32_validate(s, b);
if (ret != XZ_STREAM_END)
return ret;
}
s->sequence = SEQ_BLOCK_START;
break;
case SEQ_INDEX:
ret = dec_index(s, b);
if (ret != XZ_STREAM_END)
return ret;
s->sequence = SEQ_INDEX_PADDING;
case SEQ_INDEX_PADDING:
while ((s->index.size + (b->in_pos - s->in_start))
& 3) {
if (b->in_pos == b->in_size) {
index_update(s, b);
return XZ_OK;
}
if (b->in[b->in_pos++] != 0)
return XZ_DATA_ERROR;
}
/* Finish the CRC32 value and Index size. */
index_update(s, b);
/* Compare the hashes to validate the Index field. */
if (! memeq(&s->block.hash, &s->index.hash, sizeof(s->block.hash)))
return XZ_DATA_ERROR;
s->sequence = SEQ_INDEX_CRC32;
case SEQ_INDEX_CRC32:
ret = crc32_validate(s, b);
if (ret != XZ_STREAM_END)
return ret;
s->temp.size = STREAM_HEADER_SIZE;
s->sequence = SEQ_STREAM_FOOTER;
case SEQ_STREAM_FOOTER:
if (!fill_temp(s, b))
return XZ_OK;
return dec_stream_footer(s);
}
}
/* Never reached */
}
/*
* xz_dec_run() is a wrapper for dec_main() to handle some special cases in
* multi-call and single-call decoding.
*
* In multi-call mode, we must return XZ_BUF_ERROR when it seems clear that we
* are not going to make any progress anymore. This is to prevent the caller
* from calling us infinitely when the input file is truncated or otherwise
* corrupt. Since zlib-style API allows that the caller fills the input buffer
* only when the decoder doesn't produce any new output, we have to be careful
* to avoid returning XZ_BUF_ERROR too easily: XZ_BUF_ERROR is returned only
* after the second consecutive call to xz_dec_run() that makes no progress.
*
* In single-call mode, if we couldn't decode everything and no error
* occurred, either the input is truncated or the output buffer is too small.
* Since we know that the last input byte never produces any output, we know
* that if all the input was consumed and decoding wasn't finished, the file
* must be corrupt. Otherwise the output buffer has to be too small or the
* file is corrupt in a way that decoding it produces too big output.
*
* If single-call decoding fails, we reset b->in_pos and b->out_pos back to
* their original values. This is because with some filter chains there won't
* be any valid uncompressed data in the output buffer unless the decoding
* actually succeeds (that's the price to pay of using the output buffer as
* the workspace).
*/
enum xz_ret xz_dec_run(struct xz_dec *s, struct xz_buf *b)
{
size_t in_start;
size_t out_start;
enum xz_ret ret;
if (s->single_call)
xz_dec_reset(s);
in_start = b->in_pos;
out_start = b->out_pos;
ret = dec_main(s, b);
if (s->single_call) {
if (ret == XZ_OK)
ret = b->in_pos == b->in_size
? XZ_DATA_ERROR : XZ_BUF_ERROR;
if (ret != XZ_STREAM_END) {
b->in_pos = in_start;
b->out_pos = out_start;
}
} else if (ret == XZ_OK && in_start == b->in_pos
&& out_start == b->out_pos) {
if (s->allow_buf_error)
ret = XZ_BUF_ERROR;
s->allow_buf_error = true;
} else {
s->allow_buf_error = false;
}
return ret;
}
struct xz_dec * xz_dec_init(uint32_t dict_max)
{
struct xz_dec *s = kmalloc(sizeof(*s), GFP_KERNEL);
if (s == NULL)
return NULL;
/* prepare CRC32 calculators */
if(GRUB_MD_CRC32 == NULL)
{
kfree(s);
return NULL;
}
s->crc32_context = kmalloc(GRUB_MD_CRC32->contextsize, GFP_KERNEL);
if (s->crc32_context == NULL)
{
kfree(s);
return NULL;
}
s->index.hash.crc32_context = kmalloc(GRUB_MD_CRC32->contextsize, GFP_KERNEL);
if (s->index.hash.crc32_context == NULL)
{
kfree(s->crc32_context);
kfree(s);
return NULL;
}
s->block.hash.crc32_context = kmalloc(GRUB_MD_CRC32->contextsize, GFP_KERNEL);
if (s->block.hash.crc32_context == NULL)
{
kfree(s->index.hash.crc32_context);
kfree(s->crc32_context);
kfree(s);
return NULL;
}
GRUB_MD_CRC32->init(s->crc32_context);
s->crc32_temp = 0;
GRUB_MD_CRC32->init(s->index.hash.crc32_context);
GRUB_MD_CRC32->init(s->block.hash.crc32_context);
s->single_call = dict_max == 0;
#ifdef XZ_DEC_BCJ
s->bcj = xz_dec_bcj_create(s->single_call);
if (s->bcj == NULL)
goto error_bcj;
#endif
s->lzma2 = xz_dec_lzma2_create(dict_max);
if (s->lzma2 == NULL)
goto error_lzma2;
xz_dec_reset(s);
return s;
error_lzma2:
#ifdef XZ_DEC_BCJ
xz_dec_bcj_end(s->bcj);
error_bcj:
#endif
kfree(s);
return NULL;
}
void xz_dec_reset(struct xz_dec *s)
{
s->sequence = SEQ_STREAM_HEADER;
s->allow_buf_error = false;
s->pos = 0;
memzero(&s->block, sizeof(s->block));
memzero(&s->index, sizeof(s->index));
s->temp.pos = 0;
s->temp.size = STREAM_HEADER_SIZE;
GRUB_MD_CRC32->init(s->crc32_context);
s->crc32_temp = 0;
GRUB_MD_CRC32->init(s->index.hash.crc32_context);
GRUB_MD_CRC32->init(s->block.hash.crc32_context);
}
void xz_dec_end(struct xz_dec *s)
{
if (s != NULL) {
xz_dec_lzma2_end(s->lzma2);
#ifdef XZ_DEC_BCJ
xz_dec_bcj_end(s->bcj);
#endif
kfree(s);
}
}

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@ -0,0 +1,236 @@
/* xz_lzma2.h - LZMA2 definitions */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2010 Free Software Foundation, Inc.
*
* GRUB is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* GRUB is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
/*
* This file is based on code from XZ embedded project
* http://tukaani.org/xz/embedded.html
*/
#ifndef XZ_LZMA2_H
#define XZ_LZMA2_H
/* dictionary size hard limit
* actual size limit is calculated as shown in 5.3.1
* http://tukaani.org/xz/xz-file-format.txt
*
* if bits > 39 dictionary_size = UINT32_MAX
* else
* dictionary_size = 2 | (bits & 1);
* dictionary_size <<= bits / 2 + 11;
*
* i.e.
* 0 - 4 KiB
* 6 - 32 KiB
* 30 - 128MiB
* 39 - 3072 MiB
* 40 - 4096 MiB - 1 B
* note: implementation supports 39 at maximum
*/
#define DICT_BIT_SIZE 30
/* Range coder constants */
#define RC_SHIFT_BITS 8
#define RC_TOP_BITS 24
#define RC_TOP_VALUE (1 << RC_TOP_BITS)
#define RC_BIT_MODEL_TOTAL_BITS 11
#define RC_BIT_MODEL_TOTAL (1 << RC_BIT_MODEL_TOTAL_BITS)
#define RC_MOVE_BITS 5
/*
* Maximum number of position states. A position state is the lowest pb
* number of bits of the current uncompressed offset. In some places there
* are different sets of probabilities for different position states.
*/
#define POS_STATES_MAX (1 << 4)
/*
* This enum is used to track which LZMA symbols have occurred most recently
* and in which order. This information is used to predict the next symbol.
*
* Symbols:
* - Literal: One 8-bit byte
* - Match: Repeat a chunk of data at some distance
* - Long repeat: Multi-byte match at a recently seen distance
* - Short repeat: One-byte repeat at a recently seen distance
*
* The symbol names are in from STATE_oldest_older_previous. REP means
* either short or long repeated match, and NONLIT means any non-literal.
*/
enum lzma_state {
STATE_LIT_LIT,
STATE_MATCH_LIT_LIT,
STATE_REP_LIT_LIT,
STATE_SHORTREP_LIT_LIT,
STATE_MATCH_LIT,
STATE_REP_LIT,
STATE_SHORTREP_LIT,
STATE_LIT_MATCH,
STATE_LIT_LONGREP,
STATE_LIT_SHORTREP,
STATE_NONLIT_MATCH,
STATE_NONLIT_REP
};
/* Total number of states */
#define STATES 12
/* The lowest 7 states indicate that the previous state was a literal. */
#define LIT_STATES 7
/* Indicate that the latest symbol was a literal. */
static inline void lzma_state_literal(enum lzma_state *state)
{
if (*state <= STATE_SHORTREP_LIT_LIT)
*state = STATE_LIT_LIT;
else if (*state <= STATE_LIT_SHORTREP)
*state -= 3;
else
*state -= 6;
}
/* Indicate that the latest symbol was a match. */
static inline void lzma_state_match(enum lzma_state *state)
{
*state = *state < LIT_STATES ? STATE_LIT_MATCH : STATE_NONLIT_MATCH;
}
/* Indicate that the latest state was a long repeated match. */
static inline void lzma_state_long_rep(enum lzma_state *state)
{
*state = *state < LIT_STATES ? STATE_LIT_LONGREP : STATE_NONLIT_REP;
}
/* Indicate that the latest symbol was a short match. */
static inline void lzma_state_short_rep(enum lzma_state *state)
{
*state = *state < LIT_STATES ? STATE_LIT_SHORTREP : STATE_NONLIT_REP;
}
/* Test if the previous symbol was a literal. */
static inline bool lzma_state_is_literal(enum lzma_state state)
{
return state < LIT_STATES;
}
/* Each literal coder is divided in three sections:
* - 0x001-0x0FF: Without match byte
* - 0x101-0x1FF: With match byte; match bit is 0
* - 0x201-0x2FF: With match byte; match bit is 1
*
* Match byte is used when the previous LZMA symbol was something else than
* a literal (that is, it was some kind of match).
*/
#define LITERAL_CODER_SIZE 0x300
/* Maximum number of literal coders */
#define LITERAL_CODERS_MAX (1 << 4)
/* Minimum length of a match is two bytes. */
#define MATCH_LEN_MIN 2
/* Match length is encoded with 4, 5, or 10 bits.
*
* Length Bits
* 2-9 4 = Choice=0 + 3 bits
* 10-17 5 = Choice=1 + Choice2=0 + 3 bits
* 18-273 10 = Choice=1 + Choice2=1 + 8 bits
*/
#define LEN_LOW_BITS 3
#define LEN_LOW_SYMBOLS (1 << LEN_LOW_BITS)
#define LEN_MID_BITS 3
#define LEN_MID_SYMBOLS (1 << LEN_MID_BITS)
#define LEN_HIGH_BITS 8
#define LEN_HIGH_SYMBOLS (1 << LEN_HIGH_BITS)
#define LEN_SYMBOLS (LEN_LOW_SYMBOLS + LEN_MID_SYMBOLS + LEN_HIGH_SYMBOLS)
/*
* Maximum length of a match is 273 which is a result of the encoding
* described above.
*/
#define MATCH_LEN_MAX (MATCH_LEN_MIN + LEN_SYMBOLS - 1)
/*
* Different sets of probabilities are used for match distances that have
* very short match length: Lengths of 2, 3, and 4 bytes have a separate
* set of probabilities for each length. The matches with longer length
* use a shared set of probabilities.
*/
#define DIST_STATES 4
/*
* Get the index of the appropriate probability array for decoding
* the distance slot.
*/
static inline uint32_t lzma_get_dist_state(uint32_t len)
{
return len < DIST_STATES + MATCH_LEN_MIN
? len - MATCH_LEN_MIN : DIST_STATES - 1;
}
/*
* The highest two bits of a 32-bit match distance are encoded using six bits.
* This six-bit value is called a distance slot. This way encoding a 32-bit
* value takes 6-36 bits, larger values taking more bits.
*/
#define DIST_SLOT_BITS 6
#define DIST_SLOTS (1 << DIST_SLOT_BITS)
/* Match distances up to 127 are fully encoded using probabilities. Since
* the highest two bits (distance slot) are always encoded using six bits,
* the distances 0-3 don't need any additional bits to encode, since the
* distance slot itself is the same as the actual distance. DIST_MODEL_START
* indicates the first distance slot where at least one additional bit is
* needed.
*/
#define DIST_MODEL_START 4
/*
* Match distances greater than 127 are encoded in three pieces:
* - distance slot: the highest two bits
* - direct bits: 2-26 bits below the highest two bits
* - alignment bits: four lowest bits
*
* Direct bits don't use any probabilities.
*
* The distance slot value of 14 is for distances 128-191.
*/
#define DIST_MODEL_END 14
/* Distance slots that indicate a distance <= 127. */
#define FULL_DISTANCES_BITS (DIST_MODEL_END / 2)
#define FULL_DISTANCES (1 << FULL_DISTANCES_BITS)
/*
* For match distances greater than 127, only the highest two bits and the
* lowest four bits (alignment) is encoded using probabilities.
*/
#define ALIGN_BITS 4
#define ALIGN_SIZE (1 << ALIGN_BITS)
#define ALIGN_MASK (ALIGN_SIZE - 1)
/* Total number of all probability variables */
#define PROBS_TOTAL (1846 + LITERAL_CODERS_MAX * LITERAL_CODER_SIZE)
/*
* LZMA remembers the four most recent match distances. Reusing these
* distances tends to take less space than re-encoding the actual
* distance value.
*/
#define REPS 4
#endif

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/* xz_private.h - Private includes and definitions */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2010 Free Software Foundation, Inc.
*
* GRUB is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* GRUB is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
/*
* This file is based on code from XZ embedded project
* http://tukaani.org/xz/embedded.html
*/
#ifndef XZ_PRIVATE_H
#define XZ_PRIVATE_H
/*
* For userspace builds, use a separate header to define the required
* macros and functions. This makes it easier to adapt the code into
* different environments and avoids clutter in the Linux kernel tree.
*/
#include "xz_config.h"
/*
* If any of the BCJ filter decoders are wanted, define XZ_DEC_BCJ.
* XZ_DEC_BCJ is used to enable generic support for BCJ decoders.
*/
#ifndef XZ_DEC_BCJ
# if defined(XZ_DEC_X86) || defined(XZ_DEC_POWERPC) \
|| defined(XZ_DEC_IA64) || defined(XZ_DEC_ARM) \
|| defined(XZ_DEC_ARM) || defined(XZ_DEC_ARMTHUMB) \
|| defined(XZ_DEC_SPARC)
# define XZ_DEC_BCJ
# endif
#endif
/*
* Allocate memory for LZMA2 decoder. xz_dec_lzma2_reset() must be used
* before calling xz_dec_lzma2_run().
*/
struct xz_dec_lzma2 * xz_dec_lzma2_create(
uint32_t dict_max);
/*
* Decode the LZMA2 properties (one byte) and reset the decoder. Return
* XZ_OK on success, XZ_MEMLIMIT_ERROR if the preallocated dictionary is not
* big enough, and XZ_OPTIONS_ERROR if props indicates something that this
* decoder doesn't support.
*/
enum xz_ret xz_dec_lzma2_reset(
struct xz_dec_lzma2 *s, uint8_t props);
/* Decode raw LZMA2 stream from b->in to b->out. */
enum xz_ret xz_dec_lzma2_run(
struct xz_dec_lzma2 *s, struct xz_buf *b);
/* Free the memory allocated for the LZMA2 decoder. */
void xz_dec_lzma2_end(struct xz_dec_lzma2 *s);
/*
* Allocate memory for BCJ decoders. xz_dec_bcj_reset() must be used before
* calling xz_dec_bcj_run().
*/
struct xz_dec_bcj * xz_dec_bcj_create(bool single_call);
/*
* Decode the Filter ID of a BCJ filter. This implementation doesn't
* support custom start offsets, so no decoding of Filter Properties
* is needed. Returns XZ_OK if the given Filter ID is supported.
* Otherwise XZ_OPTIONS_ERROR is returned.
*/
enum xz_ret xz_dec_bcj_reset(
struct xz_dec_bcj *s, uint8_t id);
/*
* Decode raw BCJ + LZMA2 stream. This must be used only if there actually is
* a BCJ filter in the chain. If the chain has only LZMA2, xz_dec_lzma2_run()
* must be called directly.
*/
enum xz_ret xz_dec_bcj_run(struct xz_dec_bcj *s,
struct xz_dec_lzma2 *lzma2, struct xz_buf *b);
/* Free the memory allocated for the BCJ filters. */
#define xz_dec_bcj_end(s) kfree(s)
#endif

View File

@ -0,0 +1,53 @@
/* xz_stream.h - Definitions for handling the .xz file format */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2010 Free Software Foundation, Inc.
*
* GRUB is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* GRUB is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
/*
* This file is based on code from XZ embedded project
* http://tukaani.org/xz/embedded.html
*/
#ifndef XZ_STREAM_H
#define XZ_STREAM_H
/*
* See the .xz file format specification at
* http://tukaani.org/xz/xz-file-format.txt
* to understand the container format.
*/
#define STREAM_HEADER_SIZE 12
#define HEADER_MAGIC "\3757zXZ\0"
#define HEADER_MAGIC_SIZE 6
#define FOOTER_MAGIC "YZ"
#define FOOTER_MAGIC_SIZE 2
/*
* Variable-length integer can hold a 63-bit unsigned integer, or a special
* value to indicate that the value is unknown.
*/
typedef uint64_t vli_type;
#define VLI_MAX ((vli_type)-1 / 2)
#define VLI_UNKNOWN ((vli_type)-1)
/* Maximum encoded size of a VLI */
#define VLI_BYTES_MAX (sizeof(vli_type) * 8 / 7)
#endif

View File

@ -55,9 +55,10 @@ typedef struct grub_file *grub_file_t;
typedef enum grub_file_filter_id
{
GRUB_FILE_FILTER_GZIO,
GRUB_FILE_FILTER_XZIO,
GRUB_FILE_FILTER_MAX,
GRUB_FILE_FILTER_COMPRESSION_FIRST = GRUB_FILE_FILTER_GZIO,
GRUB_FILE_FILTER_COMPRESSION_LAST = GRUB_FILE_FILTER_GZIO,
GRUB_FILE_FILTER_COMPRESSION_LAST = GRUB_FILE_FILTER_XZIO,
} grub_file_filter_id_t;
typedef grub_file_t (*grub_file_filter_t) (grub_file_t in);