Merge branch '2019-04-22-master-imports'
[platform/kernel/u-boot.git] / lib / lz4_wrapper.c
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 <linux/kernel.h>
10 #include <linux/types.h>
11
12 static u16 LZ4_readLE16(const void *src) { return le16_to_cpu(*(u16 *)src); }
13 static void LZ4_copy4(void *dst, const void *src) { *(u32 *)dst = *(u32 *)src; }
14 static void LZ4_copy8(void *dst, const void *src) { *(u64 *)dst = *(u64 *)src; }
15
16 typedef  uint8_t BYTE;
17 typedef uint16_t U16;
18 typedef uint32_t U32;
19 typedef  int32_t S32;
20 typedef uint64_t U64;
21
22 #define FORCE_INLINE static inline __attribute__((always_inline))
23
24 /* Unaltered (except removing unrelated code) from github.com/Cyan4973/lz4. */
25 #include "lz4.c"        /* #include for inlining, do not link! */
26
27 struct lz4_frame_header {
28         u32 magic;
29         union {
30                 u8 flags;
31                 struct {
32                         u8 reserved0:2;
33                         u8 has_content_checksum:1;
34                         u8 has_content_size:1;
35                         u8 has_block_checksum:1;
36                         u8 independent_blocks:1;
37                         u8 version:2;
38                 };
39         };
40         union {
41                 u8 block_descriptor;
42                 struct {
43                         u8 reserved1:4;
44                         u8 max_block_size:3;
45                         u8 reserved2:1;
46                 };
47         };
48         /* + u64 content_size iff has_content_size is set */
49         /* + u8 header_checksum */
50 } __packed;
51
52 struct lz4_block_header {
53         union {
54                 u32 raw;
55                 struct {
56                         u32 size:31;
57                         u32 not_compressed:1;
58                 };
59         };
60         /* + size bytes of data */
61         /* + u32 block_checksum iff has_block_checksum is set */
62 } __packed;
63
64 int ulz4fn(const void *src, size_t srcn, void *dst, size_t *dstn)
65 {
66         const void *end = dst + *dstn;
67         const void *in = src;
68         void *out = dst;
69         int has_block_checksum;
70         int ret;
71         *dstn = 0;
72
73         { /* With in-place decompression the header may become invalid later. */
74                 const struct lz4_frame_header *h = in;
75
76                 if (srcn < sizeof(*h) + sizeof(u64) + sizeof(u8))
77                         return -EINVAL; /* input overrun */
78
79                 /* We assume there's always only a single, standard frame. */
80                 if (le32_to_cpu(h->magic) != LZ4F_MAGIC || h->version != 1)
81                         return -EPROTONOSUPPORT;        /* unknown format */
82                 if (h->reserved0 || h->reserved1 || h->reserved2)
83                         return -EINVAL; /* reserved must be zero */
84                 if (!h->independent_blocks)
85                         return -EPROTONOSUPPORT; /* we can't support this yet */
86                 has_block_checksum = h->has_block_checksum;
87
88                 in += sizeof(*h);
89                 if (h->has_content_size)
90                         in += sizeof(u64);
91                 in += sizeof(u8);
92         }
93
94         while (1) {
95                 struct lz4_block_header b;
96
97                 b.raw = le32_to_cpu(*(u32 *)in);
98                 in += sizeof(struct lz4_block_header);
99
100                 if (in - src + b.size > srcn) {
101                         ret = -EINVAL;          /* input overrun */
102                         break;
103                 }
104
105                 if (!b.size) {
106                         ret = 0;        /* decompression successful */
107                         break;
108                 }
109
110                 if (b.not_compressed) {
111                         size_t size = min((ptrdiff_t)b.size, end - out);
112                         memcpy(out, in, size);
113                         out += size;
114                         if (size < b.size) {
115                                 ret = -ENOBUFS; /* output overrun */
116                                 break;
117                         }
118                 } else {
119                         /* constant folding essential, do not touch params! */
120                         ret = LZ4_decompress_generic(in, out, b.size,
121                                         end - out, endOnInputSize,
122                                         full, 0, noDict, out, NULL, 0);
123                         if (ret < 0) {
124                                 ret = -EPROTO;  /* decompression error */
125                                 break;
126                         }
127                         out += ret;
128                 }
129
130                 in += b.size;
131                 if (has_block_checksum)
132                         in += sizeof(u32);
133         }
134
135         *dstn = out - dst;
136         return ret;
137 }