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138 lines
3.1 KiB
138 lines
3.1 KiB
// SPDX-License-Identifier: GPL 2.0+ OR BSD-3-Clause |
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/* |
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* Copyright 2015 Google Inc. |
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*/ |
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#include <common.h> |
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#include <compiler.h> |
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#include <linux/kernel.h> |
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#include <linux/types.h> |
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static u16 LZ4_readLE16(const void *src) { return le16_to_cpu(*(u16 *)src); } |
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static void LZ4_copy4(void *dst, const void *src) { *(u32 *)dst = *(u32 *)src; } |
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static void LZ4_copy8(void *dst, const void *src) { *(u64 *)dst = *(u64 *)src; } |
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typedef uint8_t BYTE; |
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typedef uint16_t U16; |
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typedef uint32_t U32; |
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typedef int32_t S32; |
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typedef uint64_t U64; |
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#define FORCE_INLINE static inline __attribute__((always_inline)) |
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/* Unaltered (except removing unrelated code) from github.com/Cyan4973/lz4. */ |
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#include "lz4.c" /* #include for inlining, do not link! */ |
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#define LZ4F_MAGIC 0x184D2204 |
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struct lz4_frame_header { |
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u32 magic; |
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union { |
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u8 flags; |
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struct { |
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u8 reserved0:2; |
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u8 has_content_checksum:1; |
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u8 has_content_size:1; |
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u8 has_block_checksum:1; |
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u8 independent_blocks:1; |
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u8 version:2; |
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}; |
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}; |
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union { |
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u8 block_descriptor; |
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struct { |
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u8 reserved1:4; |
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u8 max_block_size:3; |
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u8 reserved2:1; |
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}; |
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}; |
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/* + u64 content_size iff has_content_size is set */ |
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/* + u8 header_checksum */ |
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} __packed; |
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struct lz4_block_header { |
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union { |
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u32 raw; |
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struct { |
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u32 size:31; |
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u32 not_compressed:1; |
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}; |
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}; |
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/* + size bytes of data */ |
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/* + u32 block_checksum iff has_block_checksum is set */ |
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} __packed; |
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int ulz4fn(const void *src, size_t srcn, void *dst, size_t *dstn) |
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{ |
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const void *end = dst + *dstn; |
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const void *in = src; |
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void *out = dst; |
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int has_block_checksum; |
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int ret; |
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*dstn = 0; |
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{ /* With in-place decompression the header may become invalid later. */ |
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const struct lz4_frame_header *h = in; |
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if (srcn < sizeof(*h) + sizeof(u64) + sizeof(u8)) |
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return -EINVAL; /* input overrun */ |
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/* We assume there's always only a single, standard frame. */ |
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if (le32_to_cpu(h->magic) != LZ4F_MAGIC || h->version != 1) |
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return -EPROTONOSUPPORT; /* unknown format */ |
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if (h->reserved0 || h->reserved1 || h->reserved2) |
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return -EINVAL; /* reserved must be zero */ |
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if (!h->independent_blocks) |
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return -EPROTONOSUPPORT; /* we can't support this yet */ |
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has_block_checksum = h->has_block_checksum; |
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in += sizeof(*h); |
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if (h->has_content_size) |
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in += sizeof(u64); |
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in += sizeof(u8); |
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} |
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while (1) { |
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struct lz4_block_header b; |
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b.raw = le32_to_cpu(*(u32 *)in); |
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in += sizeof(struct lz4_block_header); |
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if (in - src + b.size > srcn) { |
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ret = -EINVAL; /* input overrun */ |
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break; |
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} |
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if (!b.size) { |
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ret = 0; /* decompression successful */ |
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break; |
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} |
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if (b.not_compressed) { |
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size_t size = min((ptrdiff_t)b.size, end - out); |
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memcpy(out, in, size); |
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out += size; |
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if (size < b.size) { |
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ret = -ENOBUFS; /* output overrun */ |
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break; |
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} |
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} else { |
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/* constant folding essential, do not touch params! */ |
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ret = LZ4_decompress_generic(in, out, b.size, |
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end - out, endOnInputSize, |
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full, 0, noDict, out, NULL, 0); |
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if (ret < 0) { |
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ret = -EPROTO; /* decompression error */ |
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break; |
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} |
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out += ret; |
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} |
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in += b.size; |
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if (has_block_checksum) |
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in += sizeof(u32); |
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} |
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*dstn = out - dst; |
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return ret; |
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}
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