diff options
Diffstat (limited to 'payloads/libpayload/liblz4/lz4_wrapper.c')
| -rw-r--r-- | payloads/libpayload/liblz4/lz4_wrapper.c | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/payloads/libpayload/liblz4/lz4_wrapper.c b/payloads/libpayload/liblz4/lz4_wrapper.c new file mode 100644 index 0000000000..b04659783d --- /dev/null +++ b/payloads/libpayload/liblz4/lz4_wrapper.c @@ -0,0 +1,158 @@ +/* + * Copyright 2015 Google Inc. + * + * 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. + * 3. The name of the author may not be used to endorse or promote products + * derived from this software without specific prior written permission. + * + * Alternatively, this software may be distributed under the terms of the + * GNU General Public License ("GPL") version 2 as published by the Free + * Software Foundation. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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 <assert.h> +#include <endian.h> +#include <libpayload.h> +#include <lz4.h> + +/* LZ4 comes with its own supposedly portable memory access functions, but they + * seem to be very inefficient in practice (at least on ARM64). Since libpayload + * knows about endinaness and allows some basic assumptions (such as unaligned + * access support), we can easily write the ones we need ourselves. */ +static u16 LZ4_readLE16(const void *src) { return le16toh(*(u16 *)src); } +static void LZ4_copy4(void *dst, const void *src) { *(u32 *)dst = *(u32 *)src; } +static void LZ4_copy8(void *dst, const void *src) { *(u64 *)dst = *(u64 *)src; } + +typedef uint8_t BYTE; +typedef uint16_t U16; +typedef uint32_t U32; +typedef int32_t S32; +typedef uint64_t U64; + +#define FORCE_INLINE static inline __attribute__((always_inline)) +#define likely(expr) __builtin_expect((expr) != 0, 1) +#define unlikely(expr) __builtin_expect((expr) != 0, 0) + +/* Unaltered (except removing unrelated code) from github.com/Cyan4973/lz4. */ +#include "lz4.c" /* #include for inlining, do not link! */ + +#define LZ4F_MAGICNUMBER 0x184D2204 + +struct lz4_frame_header { + u32 magic; + union { + u8 flags; + struct { + u8 reserved0 : 2; + u8 has_content_checksum : 1; + u8 has_content_size : 1; + u8 has_block_checksum : 1; + u8 independent_blocks : 1; + u8 version : 2; + }; + }; + union { + u8 block_descriptor; + struct { + u8 reserved1 : 4; + u8 max_block_size : 3; + u8 reserved2 : 1; + }; + }; + /* + u64 content_size iff has_content_size is set */ + /* + u8 header_checksum */ +} __attribute__((packed)); + +struct lz4_block_header { + union { + u32 raw; + struct { + u32 size : 31; + u32 not_compressed : 1; + }; + }; + /* + size bytes of data */ + /* + u32 block_checksum iff has_block_checksum is set */ +} __attribute__((packed)); + +size_t ulz4fn(const void *src, size_t srcn, void *dst, size_t dstn) +{ + const void *in = src; + void *out = dst; + int has_block_checksum; + + { /* With in-place decompression the header may become invalid later. */ + const struct lz4_frame_header *h = in; + + if (srcn < sizeof(*h) + sizeof(u64) + sizeof(u8)) + return 0; /* input overrun */ + + /* We assume there's always only a single, standard frame. */ + if (le32toh(h->magic) != LZ4F_MAGICNUMBER || h->version != 1) + return 0; /* unknown format */ + if (h->reserved0 || h->reserved1 || h->reserved2) + return 0; /* reserved must be zero */ + if (!h->independent_blocks) + return 0; /* we don't support block dependency */ + has_block_checksum = h->has_block_checksum; + + in += sizeof(*h); + if (h->has_content_size) + in += sizeof(u64); + in += sizeof(u8); + } + + while (1) { + struct lz4_block_header b = { .raw = le32toh(*(u32 *)in) }; + in += sizeof(struct lz4_block_header); + + if (in - src + b.size > srcn) + return 0; /* input overrun */ + + if (!b.size) + return out - dst; /* decompression successful */ + + if (b.not_compressed) { + memcpy(out, in, b.size); + out += b.size; + } else { + /* constant folding essential, do not touch params! */ + int ret = LZ4_decompress_generic(in, out, b.size, + dst + dstn - out, endOnInputSize, + full, 0, noDict, out, NULL, 0); + if (ret < 0) + return 0; /* decompression error */ + else + out += ret; + } + + in += b.size; + if (has_block_checksum) + in += sizeof(u32); + } +} + +size_t ulz4f(const void *src, void *dst) +{ + /* LZ4 uses signed size parameters, so can't just use ((u32)-1) here. */ + return ulz4fn(src, 1*GiB, dst, 1*GiB); +} |