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// SPDX-License-Identifier: GPL-2.0+
/*
* BTRFS filesystem implementation for U-Boot
*
* 2017 Marek Behun, CZ.NIC, marek.behun@nic.cz
*/
#include "btrfs.h"
#include <linux/lzo.h>
#include <u-boot/zlib.h>
#include <asm/unaligned.h>
static u32 decompress_lzo(const u8 *cbuf, u32 clen, u8 *dbuf, u32 dlen)
{
u32 tot_len, in_len, res;
size_t out_len;
int ret;
if (clen < 4)
return -1;
tot_len = le32_to_cpu(get_unaligned((u32 *)cbuf));
cbuf += 4;
clen -= 4;
tot_len -= 4;
if (tot_len == 0 && dlen)
return -1;
if (tot_len < 4)
return -1;
res = 0;
while (tot_len > 4) {
in_len = le32_to_cpu(get_unaligned((u32 *)cbuf));
cbuf += 4;
clen -= 4;
if (in_len > clen || tot_len < 4 + in_len)
return -1;
tot_len -= 4 + in_len;
out_len = dlen;
ret = lzo1x_decompress_safe(cbuf, in_len, dbuf, &out_len);
if (ret != LZO_E_OK)
return -1;
cbuf += in_len;
clen -= in_len;
dbuf += out_len;
dlen -= out_len;
res += out_len;
}
return res;
}
/* from zutil.h */
#define PRESET_DICT 0x20
static u32 decompress_zlib(const u8 *_cbuf, u32 clen, u8 *dbuf, u32 dlen)
{
int wbits = MAX_WBITS, ret = -1;
z_stream stream;
u8 *cbuf;
u32 res;
memset(&stream, 0, sizeof(stream));
cbuf = (u8 *) _cbuf;
stream.total_in = 0;
stream.next_out = dbuf;
stream.avail_out = dlen;
stream.total_out = 0;
/* skip adler32 check if deflate and no dictionary */
if (clen > 2 && !(cbuf[1] & PRESET_DICT) &&
((cbuf[0] & 0x0f) == Z_DEFLATED) &&
!(((cbuf[0] << 8) + cbuf[1]) % 31)) {
wbits = -((cbuf[0] >> 4) + 8);
cbuf += 2;
clen -= 2;
}
if (Z_OK != inflateInit2(&stream, wbits))
return -1;
while (stream.total_in < clen) {
stream.next_in = cbuf + stream.total_in;
stream.avail_in = min((u32) (clen - stream.total_in),
(u32) btrfs_info.sb.sectorsize);
ret = inflate(&stream, Z_NO_FLUSH);
if (ret != Z_OK)
break;
}
res = stream.total_out;
inflateEnd(&stream);
if (ret != Z_STREAM_END)
return -1;
return res;
}
u32 btrfs_decompress(u8 type, const char *c, u32 clen, char *d, u32 dlen)
{
u32 res;
const u8 *cbuf;
u8 *dbuf;
cbuf = (const u8 *) c;
dbuf = (u8 *) d;
switch (type) {
case BTRFS_COMPRESS_NONE:
res = dlen < clen ? dlen : clen;
memcpy(dbuf, cbuf, res);
return res;
case BTRFS_COMPRESS_ZLIB:
return decompress_zlib(cbuf, clen, dbuf, dlen);
case BTRFS_COMPRESS_LZO:
return decompress_lzo(cbuf, clen, dbuf, dlen);
default:
printf("%s: Unsupported compression in extent: %i\n", __func__,
type);
return -1;
}
}
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