1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
|
// SPDX-License-Identifier: GPL-2.0
/*
* Verified Boot for Embedded (VBE) common functions
*
* Copyright 2024 Google LLC
* Written by Simon Glass <sjg@chromium.org>
*/
#include <blk.h>
#include <memalign.h>
#include <spl.h>
#include <u-boot/crc.h>
#include "vbe_common.h"
int vbe_get_blk(const char *storage, struct udevice **blkp)
{
struct blk_desc *desc;
char devname[16];
const char *end;
int devnum;
/* First figure out the block device */
log_debug("storage=%s\n", storage);
devnum = trailing_strtoln_end(storage, NULL, &end);
if (devnum == -1)
return log_msg_ret("num", -ENODEV);
if (end - storage >= sizeof(devname))
return log_msg_ret("end", -E2BIG);
strlcpy(devname, storage, end - storage + 1);
log_debug("dev=%s, %x\n", devname, devnum);
desc = blk_get_dev(devname, devnum);
if (!desc)
return log_msg_ret("get", -ENXIO);
*blkp = desc->bdev;
return 0;
}
int vbe_read_version(struct udevice *blk, ulong offset, char *version,
int max_size)
{
ALLOC_CACHE_ALIGN_BUFFER(u8, buf, MMC_MAX_BLOCK_LEN);
/* we can use an assert() here since we already read only one block */
assert(max_size <= MMC_MAX_BLOCK_LEN);
/*
* we can use an assert() here since reading the wrong block will just
* cause an invalid version-string to be (safely) read
*/
assert(!(offset & (MMC_MAX_BLOCK_LEN - 1)));
offset /= MMC_MAX_BLOCK_LEN;
if (blk_read(blk, offset, 1, buf) != 1)
return log_msg_ret("read", -EIO);
strlcpy(version, buf, max_size);
log_debug("version=%s\n", version);
return 0;
}
int vbe_read_nvdata(struct udevice *blk, ulong offset, ulong size, u8 *buf)
{
uint hdr_ver, hdr_size, data_size, crc;
const struct vbe_nvdata *nvd;
/* we can use an assert() here since we already read only one block */
assert(size <= MMC_MAX_BLOCK_LEN);
/*
* We can use an assert() here since reading the wrong block will just
* cause invalid state to be (safely) read. If the crc passes, then we
* obtain invalid state and it will likely cause booting to fail.
*
* VBE relies on valid values being in U-Boot's devicetree, so this
* should not every be wrong on a production device.
*/
assert(!(offset & (MMC_MAX_BLOCK_LEN - 1)));
if (offset & (MMC_MAX_BLOCK_LEN - 1))
return log_msg_ret("get", -EBADF);
offset /= MMC_MAX_BLOCK_LEN;
if (blk_read(blk, offset, 1, buf) != 1)
return log_msg_ret("read", -EIO);
nvd = (struct vbe_nvdata *)buf;
hdr_ver = (nvd->hdr & NVD_HDR_VER_MASK) >> NVD_HDR_VER_SHIFT;
hdr_size = (nvd->hdr & NVD_HDR_SIZE_MASK) >> NVD_HDR_SIZE_SHIFT;
if (hdr_ver != NVD_HDR_VER_CUR)
return log_msg_ret("hdr", -EPERM);
data_size = 1 << hdr_size;
if (!data_size || data_size > sizeof(*nvd))
return log_msg_ret("sz", -EPERM);
crc = crc8(0, buf + 1, data_size - 1);
if (crc != nvd->crc8)
return log_msg_ret("crc", -EPERM);
return 0;
}
|
