diff options
Diffstat (limited to 'tools/libxc/xc_dom_decompress_lz4.c')
-rw-r--r-- | tools/libxc/xc_dom_decompress_lz4.c | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/tools/libxc/xc_dom_decompress_lz4.c b/tools/libxc/xc_dom_decompress_lz4.c new file mode 100644 index 0000000000..47875359ab --- /dev/null +++ b/tools/libxc/xc_dom_decompress_lz4.c @@ -0,0 +1,136 @@ +#include <stdio.h> +#include <stdlib.h> +#include <inttypes.h> +#include <endian.h> +#include <stdint.h> + +#include "xg_private.h" +#include "xc_dom_decompress.h" + +#define CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS + +typedef uint8_t u8; +typedef uint16_t u16; +typedef uint32_t u32; +typedef uint64_t u64; + +#define likely(a) a +#define unlikely(a) a + +static inline uint_fast16_t le16_to_cpup(const unsigned char *buf) +{ + return buf[0] | (buf[1] << 8); +} + +static inline uint_fast32_t le32_to_cpup(const unsigned char *buf) +{ + return le16_to_cpup(buf) | ((uint32_t)le16_to_cpup(buf + 2) << 16); +} + +#include "../../xen/include/xen/lz4.h" +#include "../../xen/common/decompress.h" + +#ifndef __MINIOS__ + +#include "../../xen/common/lz4/decompress.c" + +#define ARCHIVE_MAGICNUMBER 0x184C2102 + +int xc_try_lz4_decode( + struct xc_dom_image *dom, void **blob, size_t *psize) +{ + int ret = -1; + unsigned char *inp = *blob, *output, *outp; + ssize_t size = *psize - 4; + size_t out_len, dest_len, chunksize; + const char *msg; + + if (size < 4) { + msg = "input too small"; + goto exit_0; + } + + out_len = get_unaligned_le32(inp + size); + if (xc_dom_kernel_check_size(dom, out_len)) { + msg = "Decompressed image too large"; + goto exit_0; + } + + output = malloc(out_len); + if (!output) { + msg = "Could not allocate output buffer"; + goto exit_0; + } + outp = output; + + chunksize = get_unaligned_le32(inp); + if (chunksize == ARCHIVE_MAGICNUMBER) { + inp += 4; + size -= 4; + } else { + msg = "invalid header"; + goto exit_2; + } + + for (;;) { + if (size < 4) { + msg = "missing data"; + goto exit_2; + } + chunksize = get_unaligned_le32(inp); + if (chunksize == ARCHIVE_MAGICNUMBER) { + inp += 4; + size -= 4; + continue; + } + inp += 4; + size -= 4; + if (chunksize > size) { + msg = "insufficient input data"; + goto exit_2; + } + + dest_len = out_len - (outp - output); + ret = lz4_decompress_unknownoutputsize(inp, chunksize, outp, + &dest_len); + if (ret < 0) { + msg = "decoding failed"; + goto exit_2; + } + + outp += dest_len; + size -= chunksize; + + if (size == 0) + { + *blob = output; + *psize = out_len; + return 0; + } + + if (size < 0) { + msg = "data corrupted"; + goto exit_2; + } + + inp += chunksize; + } + +exit_2: + free(output); +exit_0: + DOMPRINTF("LZ4 decompression error: %s\n", msg); + return ret; +} + +#else /* __MINIOS__ */ + +#include "../../xen/common/unlz4.c" + +int xc_try_lz4_decode( + struct xc_dom_image *dom, void **blob, size_t *size) +{ + return xc_dom_decompress_unsafe(unlz4, dom, blob, size); +} + +#endif |