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
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
|
/*
* Copyright (C) 2019 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 "updater/updater_runtime.h"
#include <string.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <unistd.h>
#include <android-base/file.h>
#include <android-base/logging.h>
#include <android-base/properties.h>
#include <android-base/strings.h>
#include <android-base/unique_fd.h>
#include <ext4_utils/wipe.h>
#include <fs_mgr.h>
#include <selinux/label.h>
#include <tune2fs.h>
#include "mounts.h"
#include "otautil/sysutil.h"
std::string UpdaterRuntime::GetProperty(const std::string_view key,
const std::string_view default_value) const {
return android::base::GetProperty(std::string(key), std::string(default_value));
}
std::string UpdaterRuntime::FindBlockDeviceName(const std::string_view name) const {
return std::string(name);
}
static struct {
const char* name;
unsigned flag;
} mount_flags_list[] = {
{ "noatime", MS_NOATIME },
{ "noexec", MS_NOEXEC },
{ "nosuid", MS_NOSUID },
{ "nodev", MS_NODEV },
{ "nodiratime", MS_NODIRATIME },
{ "ro", MS_RDONLY },
{ "rw", 0 },
{ "remount", MS_REMOUNT },
{ "bind", MS_BIND },
{ "rec", MS_REC },
{ "unbindable", MS_UNBINDABLE },
{ "private", MS_PRIVATE },
{ "slave", MS_SLAVE },
{ "shared", MS_SHARED },
{ "defaults", 0 },
{ 0, 0 },
};
static bool setMountFlag(const std::string& flag, unsigned* mount_flags) {
for (const auto& [name, value] : mount_flags_list) {
if (flag == name) {
*mount_flags |= value;
return true;
}
}
return false;
}
static bool parseMountFlags(const std::string& flags, unsigned* mount_flags,
std::string* fs_options) {
bool is_flag_set = false;
std::vector<std::string> flag_list;
for (const auto& flag : android::base::Split(flags, ",")) {
if (!setMountFlag(flag, mount_flags)) {
// Unknown flag, so it must be a filesystem specific option.
flag_list.push_back(flag);
} else {
is_flag_set = true;
}
}
*fs_options = android::base::Join(flag_list, ',');
return is_flag_set;
}
int UpdaterRuntime::Mount(const std::string_view location, const std::string_view mount_point,
const std::string_view fs_type, const std::string_view mount_options) {
std::string mount_point_string(mount_point);
std::string mount_options_string(mount_options);
char* secontext = nullptr;
unsigned mount_flags = 0;
std::string fs_options;
if (sehandle_) {
selabel_lookup(sehandle_, &secontext, mount_point_string.c_str(), 0755);
setfscreatecon(secontext);
}
mkdir(mount_point_string.c_str(), 0755);
if (secontext) {
freecon(secontext);
setfscreatecon(nullptr);
}
if (!parseMountFlags(mount_options_string, &mount_flags, &fs_options)) {
// Fall back to default
mount_flags = MS_NOATIME | MS_NODEV | MS_NODIRATIME;
}
return mount(std::string(location).c_str(), mount_point_string.c_str(),
std::string(fs_type).c_str(), mount_flags, fs_options.c_str());
}
bool UpdaterRuntime::IsMounted(const std::string_view mount_point) const {
scan_mounted_volumes();
MountedVolume* vol = find_mounted_volume_by_mount_point(std::string(mount_point).c_str());
return vol != nullptr;
}
std::pair<bool, int> UpdaterRuntime::Unmount(const std::string_view mount_point) {
scan_mounted_volumes();
MountedVolume* vol = find_mounted_volume_by_mount_point(std::string(mount_point).c_str());
if (vol == nullptr) {
return { false, -1 };
}
int ret = unmount_mounted_volume(vol);
return { true, ret };
}
bool UpdaterRuntime::ReadFileToString(const std::string_view filename, std::string* content) const {
return android::base::ReadFileToString(std::string(filename), content);
}
bool UpdaterRuntime::WriteStringToFile(const std::string_view content,
const std::string_view filename) const {
return android::base::WriteStringToFile(std::string(content), std::string(filename));
}
int UpdaterRuntime::WipeBlockDevice(const std::string_view filename, size_t len) const {
android::base::unique_fd fd(open(std::string(filename).c_str(), O_WRONLY));
if (fd == -1) {
PLOG(ERROR) << "Failed to open " << filename;
return false;
}
// The wipe_block_device function in ext4_utils returns 0 on success and 1 for failure.
return wipe_block_device(fd, len);
}
int UpdaterRuntime::RunProgram(const std::vector<std::string>& args, bool is_vfork) const {
CHECK(!args.empty());
auto argv = StringVectorToNullTerminatedArray(args);
LOG(INFO) << "about to run program [" << args[0] << "] with " << argv.size() << " args";
pid_t child = is_vfork ? vfork() : fork();
if (child == 0) {
execv(argv[0], argv.data());
PLOG(ERROR) << "run_program: execv failed";
_exit(EXIT_FAILURE);
}
int status;
waitpid(child, &status, 0);
if (WIFEXITED(status)) {
if (WEXITSTATUS(status) != 0) {
LOG(ERROR) << "run_program: child exited with status " << WEXITSTATUS(status);
}
} else if (WIFSIGNALED(status)) {
LOG(ERROR) << "run_program: child terminated by signal " << WTERMSIG(status);
}
return status;
}
int UpdaterRuntime::Tune2Fs(const std::vector<std::string>& args) const {
auto tune2fs_args = StringVectorToNullTerminatedArray(args);
// tune2fs changes the filesystem parameters on an ext2 filesystem; it returns 0 on success.
return tune2fs_main(tune2fs_args.size() - 1, tune2fs_args.data());
}
std::string UpdaterRuntime::AddSlotSuffix(const std::string_view arg) const {
return std::string(arg) + fs_mgr_get_slot_suffix();
}
|
