diff options
Diffstat (limited to 'lib/decompress_unlzo.c')
| -rw-r--r-- | lib/decompress_unlzo.c | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/lib/decompress_unlzo.c b/lib/decompress_unlzo.c new file mode 100644 index 0000000000..8f9cdcf27b --- /dev/null +++ b/lib/decompress_unlzo.c @@ -0,0 +1,199 @@ +/* + * LZO decompressor for barebox. Code borrowed from the lzo + * implementation by Markus Franz Xaver Johannes Oberhumer. + * + * Linux kernel adaptation: + * Copyright (C) 2009 + * Albin Tonnerre, Free Electrons <albin.tonnerre@free-electrons.com> + * + * Original code: + * Copyright (C) 1996-2005 Markus Franz Xaver Johannes Oberhumer + * All Rights Reserved. + * + * lzop and the LZO library are free software; you can redistribute them + * and/or modify them under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program 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 this program; see the file COPYING. + * If not, write to the Free Software Foundation, Inc., + * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * + * Markus F.X.J. Oberhumer + * <markus@oberhumer.com> + * http://www.oberhumer.com/opensource/lzop/ + */ + +#include <common.h> +#include <malloc.h> +#include <linux/types.h> +#include <lzo.h> +#include <errno.h> +#include <fs.h> +#include <xfuncs.h> + +#include <linux/compiler.h> +#include <asm/unaligned.h> + +static const unsigned char lzop_magic[] = { + 0x89, 0x4c, 0x5a, 0x4f, 0x00, 0x0d, 0x0a, 0x1a, 0x0a }; + +#define LZO_BLOCK_SIZE (256*1024l) +#define HEADER_HAS_FILTER 0x00000800L + +static inline int parse_header(int in_fd) +{ + u8 l; + u16 version; + int ret; + unsigned char buf[256]; /* maximum filename length + 1 */ + + /* read magic (9), library version (2), 'need to be extracted' + * version (2) and method (1) + */ + ret = read(in_fd, buf, 9); + if (ret < 0) + return ret; + + /* check magic */ + for (l = 0; l < 9; l++) { + if (buf[l] != lzop_magic[l]) + return -EINVAL; + } + + ret = read(in_fd, buf, 4); /* version, lib_version */ + if (ret < 0) + return ret; + version = get_unaligned_be16(buf); + + if (version >= 0x0940) { + ret = read(in_fd, buf, 2); /* version to extract */ + if (ret < 0) + return ret; + } + + ret = read(in_fd, buf, 1); /* method */ + if (ret < 0) + return ret; + + if (version >= 0x0940) + read(in_fd, buf, 1); /* level */ + + ret = read(in_fd, buf, 4); /* flags */ + if (ret < 0) + return ret; + + if (get_unaligned_be32(buf) & HEADER_HAS_FILTER) { + ret = read(in_fd, buf, 4); /* skip filter info */ + if (ret < 0) + return ret; + } + + /* skip mode and mtime_low */ + ret = read(in_fd, buf, 8); + if (ret < 0) + return ret; + + if (version >= 0x0940) { + ret = read(in_fd, buf, 4); /* skip mtime_high */ + if (ret < 0) + return ret; + } + + ret = read(in_fd, &l, 1); + if (ret < 0) + return ret; + /* don't care about the file name, and skip checksum */ + ret = read(in_fd, buf, l + 4); + if (ret < 0) + return ret; + + return 0; +} + +int unlzo(int in_fd, int out_fd, int *dest_len) +{ + u8 r = 0; + u32 src_len, dst_len; + size_t tmp; + u8 *in_buf, *out_buf; + int obytes_processed = 0; + unsigned char buf[8]; + int ret; + + if (parse_header(in_fd)) + return -EINVAL; + + out_buf = xmalloc(LZO_BLOCK_SIZE); + in_buf = xmalloc(lzo1x_worst_compress(LZO_BLOCK_SIZE)); + + for (;;) { + /* read uncompressed block size */ + ret = read(in_fd, buf, 4); + if (ret < 0) + goto exit_free; + dst_len = get_unaligned_be32(buf); + + /* exit if last block */ + if (dst_len == 0) + break; + + if (dst_len > LZO_BLOCK_SIZE) { + printf("dest len longer than block size"); + goto exit_free; + } + + /* read compressed block size, and skip block checksum info */ + ret = read(in_fd, buf, 8); + if (ret < 0) + goto exit_free; + + src_len = get_unaligned_be32(buf); + + if (src_len <= 0 || src_len > dst_len) { + printf("file corrupted"); + goto exit_free; + } + ret = read(in_fd, in_buf, src_len); + if (ret < 0) + goto exit_free; + + /* decompress */ + tmp = dst_len; + if (src_len < dst_len) { + r = lzo1x_decompress_safe((u8 *) in_buf, src_len, + out_buf, &tmp); + if (r != LZO_E_OK || dst_len != tmp) { + printf("Compressed data violation"); + goto exit_free; + } + ret = write(out_fd, out_buf, dst_len); + if (ret < 0) + goto exit_free; + } else { + if (src_len != dst_len) { + printf("Compressed data violation"); + goto exit_free; + } + ret = write(out_fd, in_buf, dst_len); + if (ret < 0) + goto exit_free; + } + + obytes_processed += dst_len; + } + +exit_free: + free(in_buf); + free(out_buf); + + *dest_len = obytes_processed; + return 0; +} + |