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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /lib/decompress.c | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | lib/decompress.c | 84 |
1 files changed, 84 insertions, 0 deletions
diff --git a/lib/decompress.c b/lib/decompress.c new file mode 100644 index 0000000000..ab3fc90ffc --- /dev/null +++ b/lib/decompress.c @@ -0,0 +1,84 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * decompress.c + * + * Detect the decompression method based on magic number + */ + +#include <linux/decompress/generic.h> + +#include <linux/decompress/bunzip2.h> +#include <linux/decompress/unlzma.h> +#include <linux/decompress/unxz.h> +#include <linux/decompress/inflate.h> +#include <linux/decompress/unlzo.h> +#include <linux/decompress/unlz4.h> +#include <linux/decompress/unzstd.h> + +#include <linux/types.h> +#include <linux/string.h> +#include <linux/init.h> +#include <linux/printk.h> + +#ifndef CONFIG_DECOMPRESS_GZIP +# define gunzip NULL +#endif +#ifndef CONFIG_DECOMPRESS_BZIP2 +# define bunzip2 NULL +#endif +#ifndef CONFIG_DECOMPRESS_LZMA +# define unlzma NULL +#endif +#ifndef CONFIG_DECOMPRESS_XZ +# define unxz NULL +#endif +#ifndef CONFIG_DECOMPRESS_LZO +# define unlzo NULL +#endif +#ifndef CONFIG_DECOMPRESS_LZ4 +# define unlz4 NULL +#endif +#ifndef CONFIG_DECOMPRESS_ZSTD +# define unzstd NULL +#endif + +struct compress_format { + unsigned char magic[2]; + const char *name; + decompress_fn decompressor; +}; + +static const struct compress_format compressed_formats[] __initconst = { + { {0x1f, 0x8b}, "gzip", gunzip }, + { {0x1f, 0x9e}, "gzip", gunzip }, + { {0x42, 0x5a}, "bzip2", bunzip2 }, + { {0x5d, 0x00}, "lzma", unlzma }, + { {0xfd, 0x37}, "xz", unxz }, + { {0x89, 0x4c}, "lzo", unlzo }, + { {0x02, 0x21}, "lz4", unlz4 }, + { {0x28, 0xb5}, "zstd", unzstd }, + { {0, 0}, NULL, NULL } +}; + +decompress_fn __init decompress_method(const unsigned char *inbuf, long len, + const char **name) +{ + const struct compress_format *cf; + + if (len < 2) { + if (name) + *name = NULL; + return NULL; /* Need at least this much... */ + } + + pr_debug("Compressed data magic: %#.2x %#.2x\n", inbuf[0], inbuf[1]); + + for (cf = compressed_formats; cf->name; cf++) { + if (!memcmp(inbuf, cf->magic, 2)) + break; + + } + if (name) + *name = cf->name; + return cf->decompressor; +} |