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
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
|
/*
* Copyright (C) 2015 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <errno.h>
#include <fcntl.h>
#include <linux/fs.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <cutils/properties.h>
#include <bootloader.h>
#include <fs_mgr.h>
#include "bootinfo.h"
// Open the appropriate fstab file and fallback to /fstab.device if
// that's what's being used.
static struct fstab *open_fstab(void)
{
char propbuf[PROPERTY_VALUE_MAX];
char fstab_name[PROPERTY_VALUE_MAX + 32];
struct fstab *fstab;
property_get("ro.hardware", propbuf, "");
snprintf(fstab_name, sizeof(fstab_name), "/fstab.%s", propbuf);
fstab = fs_mgr_read_fstab(fstab_name);
if (fstab != NULL) {
return fstab;
} else {
fstab = fs_mgr_read_fstab("/fstab.device");
if (fstab != NULL)
return fstab;
}
return NULL;
}
static int boot_info_open_misc(int flags)
{
char *path;
int fd;
struct fstab *fstab;
struct fstab_rec *record;
fstab = open_fstab();
if (fstab == NULL)
return -1;
record = fs_mgr_get_entry_for_mount_point(fstab, "/misc");
if (record == NULL) {
fs_mgr_free_fstab(fstab);
return -1;
}
path = strdup(record->blk_device);
fs_mgr_free_fstab(fstab);
fd = open(path, flags);
free(path);
return fd;
}
// As per struct bootloader_message which is defined in
// bootable/recovery/bootloader.h we can use the 32 bytes in the
// bootctrl_suffix field provided that they start with the active slot
// suffix terminated by NUL. It just so happens that BrilloBootInfo is
// laid out this way.
#define BOOTINFO_OFFSET offsetof(struct bootloader_message, slot_suffix)
bool boot_info_load(BrilloBootInfo *out_info)
{
int fd;
memset(out_info, '\0', sizeof(BrilloBootInfo));
fd = boot_info_open_misc(O_RDONLY);
if (fd == -1)
return false;
if (lseek(fd, BOOTINFO_OFFSET, SEEK_SET) != BOOTINFO_OFFSET) {
close(fd);
return false;
}
ssize_t num_read;
do {
num_read = read(fd, (void*) out_info, sizeof(BrilloBootInfo));
} while (num_read == -1 && errno == EINTR);
close(fd);
if (num_read != sizeof(BrilloBootInfo))
return false;
return true;
}
bool boot_info_save(BrilloBootInfo *info)
{
int fd;
fd = boot_info_open_misc(O_RDWR);
if (fd == -1)
return false;
if (lseek(fd, BOOTINFO_OFFSET, SEEK_SET) != BOOTINFO_OFFSET) {
close(fd);
return false;
}
ssize_t num_written;
do {
num_written = write(fd, (void*) info, sizeof(BrilloBootInfo));
} while (num_written == -1 && errno == EINTR);
close(fd);
if (num_written != sizeof(BrilloBootInfo))
return false;
return true;
}
bool boot_info_validate(BrilloBootInfo* info)
{
if (info->magic[0] != '\0' ||
info->magic[1] != 'B' ||
info->magic[2] != 'C')
return false;
return true;
}
void boot_info_reset(BrilloBootInfo* info)
{
memset(info, '\0', sizeof(BrilloBootInfo));
info->magic[1] = 'B';
info->magic[2] = 'C';
return;
}
|
