LXR uboot/lib/lz4

   1// SPDX-License-Identifier: GPL 2.0+ OR BSD-3-Clause
   2/*
   3 * Copyright 2015 Google Inc.
   4 */
   5
   6#include <common.h>
   7#include <compiler.h>
   8#include <image.h>
   9#include <lz4.h>
  10#include <linux/kernel.h>
  11#include <linux/types.h>
  12#include <asm/unaligned.h>
  13
  14static u16 LZ4_readLE16(const void *src)
  15{
  16        return get_unaligned_le16(src);
  17}
  18static void LZ4_copy4(void *dst, const void *src)
  19{
  20        put_unaligned(get_unaligned((const u32 *)src), (u32 *)dst);
  21}
  22static void LZ4_copy8(void *dst, const void *src)
  23{
  24        put_unaligned(get_unaligned((const u64 *)src), (u64 *)dst);
  25}
  26
  27typedef  uint8_t BYTE;
  28typedef uint16_t U16;
  29typedef uint32_t U32;
  30typedef  int32_t S32;
  31typedef uint64_t U64;
  32
  33#define FORCE_INLINE static inline __attribute__((always_inline))
  34
  35/* lz4.c is unaltered (except removing unrelated code) from github.com/Cyan4973/lz4. */
  36#include "lz4.c"        /* #include for inlining, do not link! */
  37
  38#define LZ4F_BLOCKUNCOMPRESSED_FLAG 0x80000000U
  39
  40int ulz4fn(const void *src, size_t srcn, void *dst, size_t *dstn)
  41{
  42        const void *end = dst + *dstn;
  43        const void *in = src;
  44        void *out = dst;
  45        int has_block_checksum;
  46        int ret;
  47        *dstn = 0;
  48
  49        { /* With in-place decompression the header may become invalid later. */
  50                u32 magic;
  51                u8 flags, version, independent_blocks, has_content_size;
  52                u8 block_desc;
  53
  54                if (srcn < sizeof(u32) + 3*sizeof(u8))
  55                        return -EINVAL; /* input overrun */
  56
  57                magic = get_unaligned_le32(in);
  58                in += sizeof(u32);
  59                flags = *(u8 *)in;
  60                in += sizeof(u8);
  61                block_desc = *(u8 *)in;
  62                in += sizeof(u8);
  63
  64                version = (flags >> 6) & 0x3;
  65                independent_blocks = (flags >> 5) & 0x1;
  66                has_block_checksum = (flags >> 4) & 0x1;
  67                has_content_size = (flags >> 3) & 0x1;
  68
  69                /* We assume there's always only a single, standard frame. */
  70                if (magic != LZ4F_MAGIC || version != 1)
  71                        return -EPROTONOSUPPORT;        /* unknown format */
  72                if ((flags & 0x03) || (block_desc & 0x8f))
  73                        return -EINVAL; /* reserved bits must be zero */
  74                if (!independent_blocks)
  75                        return -EPROTONOSUPPORT; /* we can't support this yet */
  76
  77                if (has_content_size) {
  78                        if (srcn < sizeof(u32) + 3*sizeof(u8) + sizeof(u64))
  79                                return -EINVAL; /* input overrun */
  80                        in += sizeof(u64);
  81                }
  82                /* Header checksum byte */
  83                in += sizeof(u8);
  84        }
  85
  86        while (1) {
  87                u32 block_header, block_size;
  88
  89                block_header = get_unaligned_le32(in);
  90                in += sizeof(u32);
  91                block_size = block_header & ~LZ4F_BLOCKUNCOMPRESSED_FLAG;
  92
  93                if (in - src + block_size > srcn) {
  94                        ret = -EINVAL;          /* input overrun */
  95                        break;
  96                }
  97
  98                if (!block_size) {
  99                        ret = 0;        /* decompression successful */
 100                        break;
 101                }
 102
 103                if (block_header & LZ4F_BLOCKUNCOMPRESSED_FLAG) {
 104                        size_t size = min((ptrdiff_t)block_size, end - out);
 105                        memcpy(out, in, size);
 106                        out += size;
 107                        if (size < block_size) {
 108                                ret = -ENOBUFS; /* output overrun */
 109                                break;
 110                        }
 111                } else {
 112                        /* constant folding essential, do not touch params! */
 113                        ret = LZ4_decompress_generic(in, out, block_size,
 114                                        end - out, endOnInputSize,
 115                                        full, 0, noDict, out, NULL, 0);
 116                        if (ret < 0) {
 117                                ret = -EPROTO;  /* decompression error */
 118                                break;
 119                        }
 120                        out += ret;
 121                }
 122
 123                in += block_size;
 124                if (has_block_checksum)
 125                        in += sizeof(u32);
 126        }
 127
 128        *dstn = out - dst;
 129        return ret;
 130}
 131