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/boot_control_android.h"
18
19#include <base/bind.h>
20#include <base/files/file_util.h>
21#include <base/logging.h>
22#include <base/strings/string_util.h>
23#include <brillo/make_unique_ptr.h>
24#include <brillo/message_loops/message_loop.h>
25
26#include "update_engine/common/utils.h"
27#include "update_engine/utils_android.h"
28
29using std::string;
30
31using android::hardware::Return;
32using android::hardware::boot::V1_0::BoolResult;
33using android::hardware::boot::V1_0::CommandResult;
34using android::hardware::boot::V1_0::IBootControl;
35using android::hardware::hidl_string;
36
37namespace {
38auto StoreResultCallback(CommandResult* dest) {
39  return [dest](const CommandResult& result) { *dest = result; };
40}
41}  // namespace
42
43namespace chromeos_update_engine {
44
45namespace boot_control {
46
47// Factory defined in boot_control.h.
48std::unique_ptr<BootControlInterface> CreateBootControl() {
49  std::unique_ptr<BootControlAndroid> boot_control(new BootControlAndroid());
50  if (!boot_control->Init()) {
51    return nullptr;
52  }
53  return std::move(boot_control);
54}
55
56}  // namespace boot_control
57
58bool BootControlAndroid::Init() {
59  module_ = IBootControl::getService();
60  if (module_ == nullptr) {
61    LOG(ERROR) << "Error getting bootctrl HIDL module.";
62    return false;
63  }
64
65  LOG(INFO) << "Loaded boot control hidl hal.";
66
67  return true;
68}
69
70unsigned int BootControlAndroid::GetNumSlots() const {
71  return module_->getNumberSlots();
72}
73
74BootControlInterface::Slot BootControlAndroid::GetCurrentSlot() const {
75  return module_->getCurrentSlot();
76}
77
78bool BootControlAndroid::GetPartitionDevice(const string& partition_name,
79                                            Slot slot,
80                                            string* device) const {
81  // We can't use fs_mgr to look up |partition_name| because fstab
82  // doesn't list every slot partition (it uses the slotselect option
83  // to mask the suffix).
84  //
85  // We can however assume that there's an entry for the /misc mount
86  // point and use that to get the device file for the misc
87  // partition. This helps us locate the disk that |partition_name|
88  // resides on. From there we'll assume that a by-name scheme is used
89  // so we can just replace the trailing "misc" by the given
90  // |partition_name| and suffix corresponding to |slot|, e.g.
91  //
92  //   /dev/block/platform/soc.0/7824900.sdhci/by-name/misc ->
93  //   /dev/block/platform/soc.0/7824900.sdhci/by-name/boot_a
94  //
95  // If needed, it's possible to relax the by-name assumption in the
96  // future by trawling /sys/block looking for the appropriate sibling
97  // of misc and then finding an entry in /dev matching the sysfs
98  // entry.
99
100  base::FilePath misc_device;
101  if (!utils::DeviceForMountPoint("/misc", &misc_device))
102    return false;
103
104  if (!utils::IsSymlink(misc_device.value().c_str())) {
105    LOG(ERROR) << "Device file " << misc_device.value() << " for /misc "
106               << "is not a symlink.";
107    return false;
108  }
109
110  string suffix;
111  auto store_suffix_cb = [&suffix](hidl_string cb_suffix) {
112    suffix = cb_suffix.c_str();
113  };
114  Return<void> ret = module_->getSuffix(slot, store_suffix_cb);
115
116  if (!ret.isOk()) {
117    LOG(ERROR) << "boot_control impl returned no suffix for slot "
118               << SlotName(slot);
119    return false;
120  }
121
122  base::FilePath path = misc_device.DirName().Append(partition_name + suffix);
123  if (!base::PathExists(path)) {
124    LOG(ERROR) << "Device file " << path.value() << " does not exist.";
125    return false;
126  }
127
128  *device = path.value();
129  return true;
130}
131
132bool BootControlAndroid::IsSlotBootable(Slot slot) const {
133  Return<BoolResult> ret = module_->isSlotBootable(slot);
134  if (!ret.isOk()) {
135    LOG(ERROR) << "Unable to determine if slot " << SlotName(slot)
136               << " is bootable: "
137               << ret.description();
138    return false;
139  }
140  if (ret == BoolResult::INVALID_SLOT) {
141    LOG(ERROR) << "Invalid slot: " << SlotName(slot);
142    return false;
143  }
144  return ret == BoolResult::TRUE;
145}
146
147bool BootControlAndroid::MarkSlotUnbootable(Slot slot) {
148  CommandResult result;
149  auto ret = module_->setSlotAsUnbootable(slot, StoreResultCallback(&result));
150  if (!ret.isOk()) {
151    LOG(ERROR) << "Unable to call MarkSlotUnbootable for slot "
152               << SlotName(slot) << ": "
153               << ret.description();
154    return false;
155  }
156  if (!result.success) {
157    LOG(ERROR) << "Unable to mark slot " << SlotName(slot)
158               << " as unbootable: " << result.errMsg.c_str();
159  }
160  return result.success;
161}
162
163bool BootControlAndroid::SetActiveBootSlot(Slot slot) {
164  CommandResult result;
165  auto ret = module_->setActiveBootSlot(slot, StoreResultCallback(&result));
166  if (!ret.isOk()) {
167    LOG(ERROR) << "Unable to call SetActiveBootSlot for slot " << SlotName(slot)
168               << ": " << ret.description();
169    return false;
170  }
171  if (!result.success) {
172    LOG(ERROR) << "Unable to set the active slot to slot " << SlotName(slot)
173               << ": " << result.errMsg.c_str();
174  }
175  return result.success;
176}
177
178bool BootControlAndroid::MarkBootSuccessfulAsync(
179    base::Callback<void(bool)> callback) {
180  CommandResult result;
181  auto ret = module_->markBootSuccessful(StoreResultCallback(&result));
182  if (!ret.isOk()) {
183    LOG(ERROR) << "Unable to call MarkBootSuccessful: "
184               << ret.description();
185    return false;
186  }
187  if (!result.success) {
188    LOG(ERROR) << "Unable to mark boot successful: " << result.errMsg.c_str();
189  }
190  return brillo::MessageLoop::current()->PostTask(
191             FROM_HERE, base::Bind(callback, result.success)) !=
192         brillo::MessageLoop::kTaskIdNull;
193}
194
195}  // namespace chromeos_update_engine
196