1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * BTRFS filesystem implementation for U-Boot
4 *
5 * 2017 Marek Behun, CZ.NIC, marek.behun@nic.cz
6 */
7
8 #include "btrfs.h"
9 #include <malloc.h>
10 #include <linux/lzo.h>
11 #include <linux/zstd.h>
12 #include <u-boot/zlib.h>
13 #include <asm/unaligned.h>
14
decompress_lzo(const u8 * cbuf,u32 clen,u8 * dbuf,u32 dlen)15 static u32 decompress_lzo(const u8 *cbuf, u32 clen, u8 *dbuf, u32 dlen)
16 {
17 u32 tot_len, in_len, res;
18 size_t out_len;
19 int ret;
20
21 if (clen < 4)
22 return -1;
23
24 tot_len = le32_to_cpu(get_unaligned((u32 *)cbuf));
25 cbuf += 4;
26 clen -= 4;
27 tot_len -= 4;
28
29 if (tot_len == 0 && dlen)
30 return -1;
31 if (tot_len < 4)
32 return -1;
33
34 res = 0;
35
36 while (tot_len > 4) {
37 in_len = le32_to_cpu(get_unaligned((u32 *)cbuf));
38 cbuf += 4;
39 clen -= 4;
40
41 if (in_len > clen || tot_len < 4 + in_len)
42 return -1;
43
44 tot_len -= 4 + in_len;
45
46 out_len = dlen;
47 ret = lzo1x_decompress_safe(cbuf, in_len, dbuf, &out_len);
48 if (ret != LZO_E_OK)
49 return -1;
50
51 cbuf += in_len;
52 clen -= in_len;
53 dbuf += out_len;
54 dlen -= out_len;
55
56 res += out_len;
57 }
58
59 return res;
60 }
61
62 /* from zutil.h */
63 #define PRESET_DICT 0x20
64
decompress_zlib(const u8 * _cbuf,u32 clen,u8 * dbuf,u32 dlen)65 static u32 decompress_zlib(const u8 *_cbuf, u32 clen, u8 *dbuf, u32 dlen)
66 {
67 int wbits = MAX_WBITS, ret = -1;
68 z_stream stream;
69 u8 *cbuf;
70 u32 res;
71
72 memset(&stream, 0, sizeof(stream));
73
74 cbuf = (u8 *) _cbuf;
75
76 stream.total_in = 0;
77
78 stream.next_out = dbuf;
79 stream.avail_out = dlen;
80 stream.total_out = 0;
81
82 /* skip adler32 check if deflate and no dictionary */
83 if (clen > 2 && !(cbuf[1] & PRESET_DICT) &&
84 ((cbuf[0] & 0x0f) == Z_DEFLATED) &&
85 !(((cbuf[0] << 8) + cbuf[1]) % 31)) {
86 wbits = -((cbuf[0] >> 4) + 8);
87 cbuf += 2;
88 clen -= 2;
89 }
90
91 if (Z_OK != inflateInit2(&stream, wbits))
92 return -1;
93
94 while (stream.total_in < clen) {
95 stream.next_in = cbuf + stream.total_in;
96 stream.avail_in = min((u32) (clen - stream.total_in),
97 (u32) btrfs_info.sb.sectorsize);
98
99 ret = inflate(&stream, Z_NO_FLUSH);
100 if (ret != Z_OK)
101 break;
102 }
103
104 res = stream.total_out;
105 inflateEnd(&stream);
106
107 if (ret != Z_STREAM_END)
108 return -1;
109
110 return res;
111 }
112
113 #define ZSTD_BTRFS_MAX_WINDOWLOG 17
114 #define ZSTD_BTRFS_MAX_INPUT (1 << ZSTD_BTRFS_MAX_WINDOWLOG)
115
decompress_zstd(const u8 * cbuf,u32 clen,u8 * dbuf,u32 dlen)116 static u32 decompress_zstd(const u8 *cbuf, u32 clen, u8 *dbuf, u32 dlen)
117 {
118 ZSTD_DStream *dstream;
119 ZSTD_inBuffer in_buf;
120 ZSTD_outBuffer out_buf;
121 void *workspace;
122 size_t wsize;
123 u32 res = -1;
124
125 wsize = ZSTD_DStreamWorkspaceBound(ZSTD_BTRFS_MAX_INPUT);
126 workspace = malloc(wsize);
127 if (!workspace) {
128 debug("%s: cannot allocate workspace of size %zu\n", __func__,
129 wsize);
130 return -1;
131 }
132
133 dstream = ZSTD_initDStream(ZSTD_BTRFS_MAX_INPUT, workspace, wsize);
134 if (!dstream) {
135 printf("%s: ZSTD_initDStream failed\n", __func__);
136 goto err_free;
137 }
138
139 in_buf.src = cbuf;
140 in_buf.pos = 0;
141 in_buf.size = clen;
142
143 out_buf.dst = dbuf;
144 out_buf.pos = 0;
145 out_buf.size = dlen;
146
147 while (1) {
148 size_t ret;
149
150 ret = ZSTD_decompressStream(dstream, &out_buf, &in_buf);
151 if (ZSTD_isError(ret)) {
152 printf("%s: ZSTD_decompressStream error %d\n", __func__,
153 ZSTD_getErrorCode(ret));
154 goto err_free;
155 }
156
157 if (in_buf.pos >= clen || !ret)
158 break;
159 }
160
161 res = out_buf.pos;
162
163 err_free:
164 free(workspace);
165 return res;
166 }
167
btrfs_decompress(u8 type,const char * c,u32 clen,char * d,u32 dlen)168 u32 btrfs_decompress(u8 type, const char *c, u32 clen, char *d, u32 dlen)
169 {
170 u32 res;
171 const u8 *cbuf;
172 u8 *dbuf;
173
174 cbuf = (const u8 *) c;
175 dbuf = (u8 *) d;
176
177 switch (type) {
178 case BTRFS_COMPRESS_NONE:
179 res = dlen < clen ? dlen : clen;
180 memcpy(dbuf, cbuf, res);
181 return res;
182 case BTRFS_COMPRESS_ZLIB:
183 return decompress_zlib(cbuf, clen, dbuf, dlen);
184 case BTRFS_COMPRESS_LZO:
185 return decompress_lzo(cbuf, clen, dbuf, dlen);
186 case BTRFS_COMPRESS_ZSTD:
187 return decompress_zstd(cbuf, clen, dbuf, dlen);
188 default:
189 printf("%s: Unsupported compression in extent: %i\n", __func__,
190 type);
191 return -1;
192 }
193 }
194