1 //
2 // Copyright (C) 2015 The Android Open Source Project
3 //
4 // Licensed under the Apache License, Version 2.0 (the "License");
5 // you may not use this file except in compliance with the License.
6 // You may obtain a copy of the License at
7 //
8 // http://www.apache.org/licenses/LICENSE-2.0
9 //
10 // Unless required by applicable law or agreed to in writing, software
11 // distributed under the License is distributed on an "AS IS" BASIS,
12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 // See the License for the specific language governing permissions and
14 // limitations under the License.
15 //
16
17 #include "update_engine/cros/image_properties.h"
18
19 #include <string>
20 #include <vector>
21
22 #include <base/files/file_util.h>
23 #include <base/logging.h>
24 #include <brillo/key_value_store.h>
25
26 #include "update_engine/common/constants.h"
27 #include "update_engine/common/hardware_interface.h"
28 #include "update_engine/common/platform_constants.h"
29 #include "update_engine/common/system_state.h"
30 #include "update_engine/common/utils.h"
31
32 namespace {
33
34 const char kLsbRelease[] = "/etc/lsb-release";
35
36 const char kLsbReleaseAppIdKey[] = "CHROMEOS_RELEASE_APPID";
37 const char kLsbReleaseAutoUpdateServerKey[] = "CHROMEOS_AUSERVER";
38 const char kLsbReleaseBoardAppIdKey[] = "CHROMEOS_BOARD_APPID";
39 const char kLsbReleaseBoardKey[] = "CHROMEOS_RELEASE_BOARD";
40 const char kLsbReleaseCanaryAppIdKey[] = "CHROMEOS_CANARY_APPID";
41 const char kLsbReleaseIsPowerwashAllowedKey[] = "CHROMEOS_IS_POWERWASH_ALLOWED";
42 const char kLsbReleaseUpdateChannelKey[] = "CHROMEOS_RELEASE_TRACK";
43 const char kLsbReleaseVersionKey[] = "CHROMEOS_RELEASE_VERSION";
44
45 const char kDefaultAppId[] = "{87efface-864d-49a5-9bb3-4b050a7c227a}";
46
47 // A prefix added to the path, used for testing.
48 const char* root_prefix = nullptr;
49
GetStringWithDefault(const brillo::KeyValueStore & store,const std::string & key,const std::string & default_value)50 std::string GetStringWithDefault(const brillo::KeyValueStore& store,
51 const std::string& key,
52 const std::string& default_value) {
53 std::string result;
54 if (store.GetString(key, &result))
55 return result;
56 LOG(INFO) << "Cannot load ImageProperty " << key << ", using default value "
57 << default_value;
58 return default_value;
59 }
60
61 enum class LsbReleaseSource {
62 kSystem,
63 kStateful,
64 };
65
66 // Loads the lsb-release properties into the key-value |store| reading the file
67 // from either the system image or the stateful partition as specified by
68 // |source|. The loaded values are added to the store, possibly overriding
69 // existing values.
LoadLsbRelease(LsbReleaseSource source,brillo::KeyValueStore * store)70 void LoadLsbRelease(LsbReleaseSource source, brillo::KeyValueStore* store) {
71 std::string path;
72 if (root_prefix)
73 path = root_prefix;
74 if (source == LsbReleaseSource::kStateful)
75 path += chromeos_update_engine::kStatefulPartition;
76 store->Load(base::FilePath(path + kLsbRelease));
77 }
78
79 } // namespace
80
81 namespace chromeos_update_engine {
82
83 namespace test {
SetImagePropertiesRootPrefix(const char * test_root_prefix)84 void SetImagePropertiesRootPrefix(const char* test_root_prefix) {
85 root_prefix = test_root_prefix;
86 }
87 } // namespace test
88
LoadImageProperties()89 ImageProperties LoadImageProperties() {
90 ImageProperties result;
91
92 brillo::KeyValueStore lsb_release;
93 LoadLsbRelease(LsbReleaseSource::kSystem, &lsb_release);
94 result.current_channel = GetStringWithDefault(
95 lsb_release, kLsbReleaseUpdateChannelKey, "stable-channel");
96
97 // In dev-mode and unofficial build we can override the image properties set
98 // in the system image with the ones from the stateful partition, except the
99 // channel of the current image.
100 HardwareInterface* const hardware = SystemState::Get()->hardware();
101 if (!hardware->IsOfficialBuild() || !hardware->IsNormalBootMode())
102 LoadLsbRelease(LsbReleaseSource::kStateful, &lsb_release);
103
104 // The release_app_id is used as the default appid, but can be override by
105 // the board appid in the general case or the canary appid for the canary
106 // channel only.
107 std::string release_app_id =
108 GetStringWithDefault(lsb_release, kLsbReleaseAppIdKey, kDefaultAppId);
109
110 result.product_id = GetStringWithDefault(
111 lsb_release, kLsbReleaseBoardAppIdKey, release_app_id);
112 result.canary_product_id = GetStringWithDefault(
113 lsb_release, kLsbReleaseCanaryAppIdKey, release_app_id);
114 result.board = GetStringWithDefault(lsb_release, kLsbReleaseBoardKey, "");
115 result.version = GetStringWithDefault(lsb_release, kLsbReleaseVersionKey, "");
116 result.omaha_url =
117 GetStringWithDefault(lsb_release,
118 kLsbReleaseAutoUpdateServerKey,
119 constants::kOmahaDefaultProductionURL);
120 // Build fingerprint not used in Chrome OS.
121 result.build_fingerprint = "";
122 result.allow_arbitrary_channels = false;
123
124 return result;
125 }
126
LoadMutableImageProperties()127 MutableImageProperties LoadMutableImageProperties() {
128 MutableImageProperties result;
129 brillo::KeyValueStore lsb_release;
130 LoadLsbRelease(LsbReleaseSource::kSystem, &lsb_release);
131 LoadLsbRelease(LsbReleaseSource::kStateful, &lsb_release);
132 result.target_channel = GetStringWithDefault(
133 lsb_release, kLsbReleaseUpdateChannelKey, "stable-channel");
134 if (!lsb_release.GetBoolean(kLsbReleaseIsPowerwashAllowedKey,
135 &result.is_powerwash_allowed))
136 result.is_powerwash_allowed = false;
137 return result;
138 }
139
StoreMutableImageProperties(const MutableImageProperties & properties)140 bool StoreMutableImageProperties(const MutableImageProperties& properties) {
141 brillo::KeyValueStore lsb_release;
142 LoadLsbRelease(LsbReleaseSource::kStateful, &lsb_release);
143 lsb_release.SetString(kLsbReleaseUpdateChannelKey, properties.target_channel);
144 lsb_release.SetBoolean(kLsbReleaseIsPowerwashAllowedKey,
145 properties.is_powerwash_allowed);
146
147 std::string root_prefix_str = root_prefix ? root_prefix : "";
148 base::FilePath path(root_prefix_str + kStatefulPartition + kLsbRelease);
149 if (!base::DirectoryExists(path.DirName()))
150 base::CreateDirectory(path.DirName());
151 return lsb_release.Save(path);
152 }
153
LogImageProperties()154 void LogImageProperties() {
155 std::string lsb_release;
156 if (utils::ReadFile(kLsbRelease, &lsb_release)) {
157 LOG(INFO) << "lsb-release inside the old rootfs:\n" << lsb_release;
158 }
159
160 std::string stateful_lsb_release;
161 if (utils::ReadFile(std::string(kStatefulPartition) + kLsbRelease,
162 &stateful_lsb_release)) {
163 LOG(INFO) << "stateful lsb-release:\n" << stateful_lsb_release;
164 }
165 }
166
167 } // namespace chromeos_update_engine
168