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android / platform / system / apex / 14da7989fbb7952b6d2cdeda637cf6b11f7673e2 / . / apexd / apexd.cpp
blob: c30a941b1edef3fe80803fbb1798cd24b9efc9ea [file] [log] [blame]
/*
* Copyright (C) 2018 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 "apexd.h"
#include "apexd_private.h"
#include "apex_constants.h"
#include "apex_database.h"
#include "apex_file.h"
#include "apex_manifest.h"
#include "apex_preinstalled_data.h"
#include "apex_shim.h"
#include "apexd_checkpoint.h"
#include "apexd_loop.h"
#include "apexd_prepostinstall.h"
#include "apexd_prop.h"
#include "apexd_session.h"
#include "apexd_utils.h"
#include "apexd_verity.h"
#include "string_log.h"
#include <ApexProperties.sysprop.h>
#include <android-base/file.h>
#include <android-base/logging.h>
#include <android-base/macros.h>
#include <android-base/properties.h>
#include <android-base/scopeguard.h>
#include <android-base/stringprintf.h>
#include <android-base/strings.h>
#include <android-base/unique_fd.h>
#include <libavb/libavb.h>
#include <libdm/dm.h>
#include <libdm/dm_table.h>
#include <libdm/dm_target.h>
#include <selinux/android.h>
#include <dirent.h>
#include <fcntl.h>
#include <linux/loop.h>
#include <sys/inotify.h>
#include <sys/ioctl.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <algorithm>
#include <array>
#include <chrono>
#include <filesystem>
#include <fstream>
#include <iomanip>
#include <iterator>
#include <memory>
#include <optional>
#include <string>
#include <thread>
#include <unordered_map>
#include <unordered_set>
using android::base::ErrnoError;
using android::base::Error;
using android::base::GetProperty;
using android::base::Join;
using android::base::ReadFully;
using android::base::Result;
using android::base::StartsWith;
using android::base::StringPrintf;
using android::base::unique_fd;
using android::dm::DeviceMapper;
using android::dm::DmDeviceState;
using android::dm::DmTable;
using android::dm::DmTargetVerity;
using apex::proto::SessionState;
namespace android {
namespace apex {
using MountedApexData = MountedApexDatabase::MountedApexData;
namespace {
// These should be in-sync with system/sepolicy/public/property_contexts
static constexpr const char* kApexStatusSysprop = "apexd.status";
static constexpr const char* kApexStatusStarting = "starting";
static constexpr const char* kApexStatusReady = "ready";
static constexpr const char* kBuildFingerprintSysprop = "ro.build.fingerprint";
// This should be in UAPI, but it's not :-(
static constexpr const char* kDmVerityRestartOnCorruption =
"restart_on_corruption";
MountedApexDatabase gMountedApexes;
CheckpointInterface* gVoldService;
bool gSupportsFsCheckpoints = false;
bool gInFsCheckpointMode = false;
static constexpr size_t kLoopDeviceSetupAttempts = 3u;
bool gBootstrap = false;
static const std::vector<std::string> kBootstrapApexes = ([]() {
std::vector<std::string> ret = {
"com.android.art",
"com.android.i18n",
"com.android.runtime",
"com.android.tzdata",
};
auto vendor_vndk_ver = GetProperty("ro.vndk.version", "");
if (vendor_vndk_ver != "") {
ret.push_back("com.android.vndk.v" + vendor_vndk_ver);
}
auto product_vndk_ver = GetProperty("ro.product.vndk.version", "");
if (product_vndk_ver != "" && product_vndk_ver != vendor_vndk_ver) {
ret.push_back("com.android.vndk.v" + product_vndk_ver);
}
return ret;
})();
static constexpr const int kNumRetriesWhenCheckpointingEnabled = 1;
bool isBootstrapApex(const ApexFile& apex) {
return std::find(kBootstrapApexes.begin(), kBootstrapApexes.end(),
apex.GetManifest().name()) != kBootstrapApexes.end();
}
// Pre-allocate loop devices so that we don't have to wait for them
// later when actually activating APEXes.
Result<void> preAllocateLoopDevices() {
auto scan = FindApexes(kApexPackageBuiltinDirs);
if (!scan.ok()) {
return scan.error();
}
auto size = 0;
for (const auto& path : *scan) {
auto apexFile = ApexFile::Open(path);
if (!apexFile.ok()) {
continue;
}
size++;
// bootstrap Apexes may be activated on separate namespaces.
if (isBootstrapApex(*apexFile)) {
size++;
}
}
// note: do not call preAllocateLoopDevices() if size == 0.
// For devices (e.g. ARC) which doesn't support loop-control
// preAllocateLoopDevices() can cause problem when it tries
// to access /dev/loop-control.
if (size == 0) {
return {};
}
return loop::preAllocateLoopDevices(size);
}
std::unique_ptr<DmTable> createVerityTable(const ApexVerityData& verity_data,
const std::string& block_device,
const std::string& hash_device,
bool restart_on_corruption) {
AvbHashtreeDescriptor* desc = verity_data.desc.get();
auto table = std::make_unique<DmTable>();
uint32_t hash_start_block = 0;
if (hash_device == block_device) {
hash_start_block = desc->tree_offset / desc->hash_block_size;
}
auto target = std::make_unique<DmTargetVerity>(
0, desc->image_size / 512, desc->dm_verity_version, block_device,
hash_device, desc->data_block_size, desc->hash_block_size,
desc->image_size / desc->data_block_size, hash_start_block,
verity_data.hash_algorithm, verity_data.root_digest, verity_data.salt);
target->IgnoreZeroBlocks();
if (restart_on_corruption) {
target->SetVerityMode(kDmVerityRestartOnCorruption);
}
table->AddTarget(std::move(target));
table->set_readonly(true);
return table;
}
// Deletes a dm-verity device with a given name and path
// Synchronizes on the device actually being deleted from userspace.
Result<void> DeleteVerityDevice(const std::string& name) {
DeviceMapper& dm = DeviceMapper::Instance();
if (!dm.DeleteDevice(name, 750ms)) {
return Error() << "Failed to delete dm-device " << name;
}
return {};
}
class DmVerityDevice {
public:
DmVerityDevice() : cleared_(true) {}
explicit DmVerityDevice(std::string name)
: name_(std::move(name)), cleared_(false) {}
DmVerityDevice(std::string name, std::string dev_path)
: name_(std::move(name)),
dev_path_(std::move(dev_path)),
cleared_(false) {}
DmVerityDevice(DmVerityDevice&& other) noexcept
: name_(std::move(other.name_)),
dev_path_(std::move(other.dev_path_)),
cleared_(other.cleared_) {
other.cleared_ = true;
}
DmVerityDevice& operator=(DmVerityDevice&& other) noexcept {
name_ = other.name_;
dev_path_ = other.dev_path_;
cleared_ = other.cleared_;
other.cleared_ = true;
return *this;
}
~DmVerityDevice() {
if (!cleared_) {
Result<void> ret = DeleteVerityDevice(name_);
if (!ret.ok()) {
LOG(ERROR) << ret.error();
}
}
}
const std::string& GetName() const { return name_; }
const std::string& GetDevPath() const { return dev_path_; }
void Release() { cleared_ = true; }
private:
std::string name_;
std::string dev_path_;
bool cleared_;
};
Result<DmVerityDevice> createVerityDevice(const std::string& name,
const DmTable& table) {
DeviceMapper& dm = DeviceMapper::Instance();
if (dm.GetState(name) != DmDeviceState::INVALID) {
// TODO: since apexd tears down devices during unmount, can this happen?
LOG(WARNING) << "Deleting existing dm device " << name;
const Result<void>& result = DeleteVerityDevice(name);
if (!result.ok()) {
// TODO: should we fail instead?
LOG(ERROR) << "Failed to delete device " << name << " : "
<< result.error();
}
}
std::string dev_path;
if (!dm.CreateDevice(name, table, &dev_path, 500ms)) {
return Errorf("Couldn't create verity device.");
}
return DmVerityDevice(name, dev_path);
}
Result<void> RemovePreviouslyActiveApexFiles(
const std::unordered_set<std::string>& affected_packages,
const std::unordered_set<std::string>& files_to_keep) {
auto all_active_apex_files = FindApexFilesByName(kActiveApexPackagesDataDir);
if (!all_active_apex_files.ok()) {
return all_active_apex_files.error();
}
for (const std::string& path : *all_active_apex_files) {
Result<ApexFile> apex_file = ApexFile::Open(path);
if (!apex_file.ok()) {
return apex_file.error();
}
const std::string& package_name = apex_file->GetManifest().name();
if (affected_packages.find(package_name) == affected_packages.end()) {
// This apex belongs to a package that wasn't part of this stage sessions,
// hence it should be kept.
continue;
}
if (files_to_keep.find(apex_file->GetPath()) != files_to_keep.end()) {
// This is a path that was staged and should be kept.
continue;
}
LOG(DEBUG) << "Deleting previously active apex " << apex_file->GetPath();
if (unlink(apex_file->GetPath().c_str()) != 0) {
return ErrnoError() << "Failed to unlink " << apex_file->GetPath();
}
}
return {};
}
// Reads the entire device to verify the image is authenticatic
Result<void> readVerityDevice(const std::string& verity_device,
uint64_t device_size) {
static constexpr int kBlockSize = 4096;
static constexpr size_t kBufSize = 1024 * kBlockSize;
std::vector<uint8_t> buffer(kBufSize);
unique_fd fd(TEMP_FAILURE_RETRY(open(verity_device.c_str(), O_RDONLY)));
if (fd.get() == -1) {
return ErrnoError() << "Can't open " << verity_device;
}
size_t bytes_left = device_size;
while (bytes_left > 0) {
size_t to_read = std::min(bytes_left, kBufSize);
if (!android::base::ReadFully(fd.get(), buffer.data(), to_read)) {
return ErrnoError() << "Can't verify " << verity_device << "; corrupted?";
}
bytes_left -= to_read;
}
return {};
}
Result<void> VerifyMountedImage(const ApexFile& apex,
const std::string& mount_point) {
auto result = apex.VerifyManifestMatches(mount_point);
if (!result.ok()) {
return result;
}
if (shim::IsShimApex(apex)) {
return shim::ValidateShimApex(mount_point, apex);
}
return {};
}
Result<MountedApexData> MountPackageImpl(const ApexFile& apex,
const std::string& mountPoint,
const std::string& device_name,
const std::string& hashtree_file,
bool verifyImage) {
LOG(VERBOSE) << "Creating mount point: " << mountPoint;
// Note: the mount point could exist in case when the APEX was activated
// during the bootstrap phase (e.g., the runtime or tzdata APEX).
// Although we have separate mount namespaces to separate the early activated
// APEXes from the normally activate APEXes, the mount points themselves
// are shared across the two mount namespaces because /apex (a tmpfs) itself
// mounted at / which is (and has to be) a shared mount. Therefore, if apexd
// finds an empty directory under /apex, it's not a problem and apexd can use
// it.
auto exists = PathExists(mountPoint);
if (!exists.ok()) {
return exists.error();
}
if (!*exists && mkdir(mountPoint.c_str(), kMkdirMode) != 0) {
return ErrnoError() << "Could not create mount point " << mountPoint;
}
auto deleter = [&mountPoint]() {
if (rmdir(mountPoint.c_str()) != 0) {
PLOG(WARNING) << "Could not rmdir " << mountPoint;
}
};
auto scope_guard = android::base::make_scope_guard(deleter);
if (!IsEmptyDirectory(mountPoint)) {
return ErrnoError() << mountPoint << " is not empty";
}
const std::string& full_path = apex.GetPath();
loop::LoopbackDeviceUniqueFd loopbackDevice;
for (size_t attempts = 1;; ++attempts) {
Result<loop::LoopbackDeviceUniqueFd> ret = loop::createLoopDevice(
full_path, apex.GetImageOffset(), apex.GetImageSize());
if (ret.ok()) {
loopbackDevice = std::move(*ret);
break;
}
if (attempts >= kLoopDeviceSetupAttempts) {
return Error() << "Could not create loop device for " << full_path << ": "
<< ret.error();
}
}
LOG(VERBOSE) << "Loopback device created: " << loopbackDevice.name;
auto verityData = apex.VerifyApexVerity();
if (!verityData.ok()) {
return Error() << "Failed to verify Apex Verity data for " << full_path
<< ": " << verityData.error();
}
std::string blockDevice = loopbackDevice.name;
MountedApexData apex_data(loopbackDevice.name, apex.GetPath(), mountPoint,
/* device_name = */ "",
/* hashtree_loop_name = */ "");
// for APEXes in immutable partitions, we don't need to mount them on
// dm-verity because they are already in the dm-verity protected partition;
// system. However, note that we don't skip verification to ensure that APEXes
// are correctly signed.
const bool mountOnVerity = !isPathForBuiltinApexes(full_path);
DmVerityDevice verityDev;
loop::LoopbackDeviceUniqueFd loop_for_hash;
if (mountOnVerity) {
std::string hash_device = loopbackDevice.name;
if (verityData->desc->tree_size == 0) {
if (auto st = PrepareHashTree(apex, *verityData, hashtree_file);
!st.ok()) {
return st.error();
}
auto create_loop_status = loop::createLoopDevice(hashtree_file, 0, 0);
if (!create_loop_status.ok()) {
return create_loop_status.error();
}
loop_for_hash = std::move(*create_loop_status);
hash_device = loop_for_hash.name;
apex_data.hashtree_loop_name = hash_device;
}
auto verityTable =
createVerityTable(*verityData, loopbackDevice.name, hash_device,
/* restart_on_corruption = */ !verifyImage);
Result<DmVerityDevice> verityDevRes =
createVerityDevice(device_name, *verityTable);
if (!verityDevRes.ok()) {
return Error() << "Failed to create Apex Verity device " << full_path
<< ": " << verityDevRes.error();
}
verityDev = std::move(*verityDevRes);
apex_data.device_name = device_name;
blockDevice = verityDev.GetDevPath();
Result<void> readAheadStatus =
loop::configureReadAhead(verityDev.GetDevPath());
if (!readAheadStatus.ok()) {
return readAheadStatus.error();
}
}
// TODO: consider moving this inside RunVerifyFnInsideTempMount.
if (mountOnVerity && verifyImage) {
Result<void> verityStatus =
readVerityDevice(blockDevice, (*verityData).desc->image_size);
if (!verityStatus.ok()) {
return verityStatus.error();
}
}
uint32_t mountFlags = MS_NOATIME | MS_NODEV | MS_DIRSYNC | MS_RDONLY;
if (apex.GetManifest().nocode()) {
mountFlags |= MS_NOEXEC;
}
if (mount(blockDevice.c_str(), mountPoint.c_str(), "ext4", mountFlags,
nullptr) == 0) {
LOG(INFO) << "Successfully mounted package " << full_path << " on "
<< mountPoint;
auto status = VerifyMountedImage(apex, mountPoint);
if (!status.ok()) {
if (umount2(mountPoint.c_str(), UMOUNT_NOFOLLOW) != 0) {
PLOG(ERROR) << "Failed to umount " << mountPoint;
}
return Error() << "Failed to verify " << full_path << ": "
<< status.error();
}
// Time to accept the temporaries as good.
verityDev.Release();
loopbackDevice.CloseGood();
loop_for_hash.CloseGood();
scope_guard.Disable(); // Accept the mount.
return apex_data;
} else {
return ErrnoError() << "Mounting failed for package " << full_path;
}
}
std::string GetHashTreeFileName(const ApexFile& apex, bool is_new) {
std::string ret =
std::string(kApexHashTreeDir) + "/" + GetPackageId(apex.GetManifest());
return is_new ? ret + ".new" : ret;
}
Result<MountedApexData> VerifyAndTempMountPackage(
const ApexFile& apex, const std::string& mount_point) {
const std::string& package_id = GetPackageId(apex.GetManifest());
LOG(DEBUG) << "Temp mounting " << package_id << " to " << mount_point;
const std::string& temp_device_name = package_id + ".tmp";
std::string hashtree_file = GetHashTreeFileName(apex, /* is_new = */ true);
if (access(hashtree_file.c_str(), F_OK) == 0) {
LOG(DEBUG) << hashtree_file << " already exists. Deleting it";
if (TEMP_FAILURE_RETRY(unlink(hashtree_file.c_str())) != 0) {
return ErrnoError() << "Failed to unlink " << hashtree_file;
}
}
return MountPackageImpl(apex, mount_point, temp_device_name,
GetHashTreeFileName(apex, /* is_new = */ true),
/* verifyImage = */ true);
}
Result<void> Unmount(const MountedApexData& data) {
LOG(DEBUG) << "Unmounting " << data.full_path << " from mount point "
<< data.mount_point;
// Lazily try to umount whatever is mounted.
if (umount2(data.mount_point.c_str(), UMOUNT_NOFOLLOW) != 0 &&
errno != EINVAL && errno != ENOENT) {
return ErrnoError() << "Failed to unmount directory " << data.mount_point;
}
// Attempt to delete the folder. If the folder is retained, other
// data may be incorrect.
if (rmdir(data.mount_point.c_str()) != 0) {
PLOG(ERROR) << "Failed to rmdir directory " << data.mount_point;
}
// Try to free up the device-mapper device.
if (!data.device_name.empty()) {
const auto& result = DeleteVerityDevice(data.device_name);
if (!result.ok()) {
return result;
}
}
// Try to free up the loop device.
auto log_fn = [](const std::string& path, const std::string& /*id*/) {
LOG(VERBOSE) << "Freeing loop device " << path << " for unmount.";
};
if (!data.loop_name.empty()) {
loop::DestroyLoopDevice(data.loop_name, log_fn);
}
if (!data.hashtree_loop_name.empty()) {
loop::DestroyLoopDevice(data.hashtree_loop_name, log_fn);
}
return {};
}
template <typename VerifyFn>
Result<void> RunVerifyFnInsideTempMount(const ApexFile& apex,
const VerifyFn& verify_fn) {
// Temp mount image of this apex to validate it was properly signed;
// this will also read the entire block device through dm-verity, so
// we can be sure there is no corruption.
const std::string& temp_mount_point =
apexd_private::GetPackageTempMountPoint(apex.GetManifest());
Result<MountedApexData> mount_status =
VerifyAndTempMountPackage(apex, temp_mount_point);
if (!mount_status.ok()) {
LOG(ERROR) << "Failed to temp mount to " << temp_mount_point << " : "
<< mount_status.error();
return mount_status.error();
}
auto cleaner = [&]() {
LOG(DEBUG) << "Unmounting " << temp_mount_point;
Result<void> result = Unmount(*mount_status);
if (!result.ok()) {
LOG(WARNING) << "Failed to unmount " << temp_mount_point << " : "
<< result.error();
}
};
auto scope_guard = android::base::make_scope_guard(cleaner);
return verify_fn(temp_mount_point);
}
template <typename HookFn, typename HookCall>
Result<void> PrePostinstallPackages(const std::vector<ApexFile>& apexes,
HookFn fn, HookCall call) {
if (apexes.empty()) {
return Errorf("Empty set of inputs");
}
// 1) Check whether the APEXes have hooks.
bool has_hooks = false;
for (const ApexFile& apex_file : apexes) {
if (!(apex_file.GetManifest().*fn)().empty()) {
has_hooks = true;
break;
}
}
// 2) If we found hooks, run the pre/post-install.
if (has_hooks) {
Result<void> install_status = (*call)(apexes);
if (!install_status.ok()) {
return install_status;
}
}
return {};
}
Result<void> PreinstallPackages(const std::vector<ApexFile>& apexes) {
return PrePostinstallPackages(apexes, &ApexManifest::preinstallhook,
&StagePreInstall);
}
Result<void> PostinstallPackages(const std::vector<ApexFile>& apexes) {
return PrePostinstallPackages(apexes, &ApexManifest::postinstallhook,
&StagePostInstall);
}
template <typename RetType, typename Fn>
RetType HandlePackages(const std::vector<std::string>& paths, Fn fn) {
// 1) Open all APEXes.
std::vector<ApexFile> apex_files;
for (const std::string& path : paths) {
Result<ApexFile> apex_file = ApexFile::Open(path);
if (!apex_file.ok()) {
return apex_file.error();
}
apex_files.emplace_back(std::move(*apex_file));
}
// 2) Dispatch.
return fn(apex_files);
}
Result<void> ValidateStagingShimApex(const ApexFile& to) {
using android::base::StringPrintf;
auto system_shim = ApexFile::Open(
StringPrintf("%s/%s", kApexPackageSystemDir, shim::kSystemShimApexName));
if (!system_shim.ok()) {
return system_shim.error();
}
auto verify_fn = [&](const std::string& system_apex_path) {
return shim::ValidateUpdate(system_apex_path, to.GetPath());
};
return RunVerifyFnInsideTempMount(*system_shim, verify_fn);
}
// A version of apex verification that happens during boot.
// This function should only verification checks that are necessary to run on
// each boot. Try to avoid putting expensive checks inside this function.
Result<void> VerifyPackageBoot(const ApexFile& apex_file) {
Result<ApexVerityData> verity_or = apex_file.VerifyApexVerity();
if (!verity_or.ok()) {
return verity_or.error();
}
if (shim::IsShimApex(apex_file)) {
// Validating shim is not a very cheap operation, but it's fine to perform
// it here since it only runs during CTS tests and will never be triggered
// during normal flow.
const auto& result = ValidateStagingShimApex(apex_file);
if (!result.ok()) {
return result;
}
}
return {};
}
// A version of apex verification that happens on submitStagedSession.
// This function contains checks that might be expensive to perform, e.g. temp
// mounting a package and reading entire dm-verity device, and shouldn't be run
// during boot.
Result<void> VerifyPackageInstall(const ApexFile& apex_file) {
const auto& verify_package_boot_status = VerifyPackageBoot(apex_file);
if (!verify_package_boot_status.ok()) {
return verify_package_boot_status;
}
Result<ApexVerityData> verity_or = apex_file.VerifyApexVerity();
constexpr const auto kSuccessFn = [](const std::string& /*mount_point*/) {
return Result<void>{};
};
return RunVerifyFnInsideTempMount(apex_file, kSuccessFn);
}
template <typename VerifyApexFn>
Result<std::vector<ApexFile>> verifyPackages(
const std::vector<std::string>& paths, const VerifyApexFn& verify_apex_fn) {
if (paths.empty()) {
return Errorf("Empty set of inputs");
}
LOG(DEBUG) << "verifyPackages() for " << Join(paths, ',');
auto verify_fn = [&](std::vector<ApexFile>& apexes) {
for (const ApexFile& apex_file : apexes) {
Result<void> result = verify_apex_fn(apex_file);
if (!result.ok()) {
return Result<std::vector<ApexFile>>(result.error());
}
}
return Result<std::vector<ApexFile>>(std::move(apexes));
};
return HandlePackages<Result<std::vector<ApexFile>>>(paths, verify_fn);
}
Result<ApexFile> verifySessionDir(const int session_id) {
std::string sessionDirPath = std::string(kStagedSessionsDir) + "/session_" +
std::to_string(session_id);
LOG(INFO) << "Scanning " << sessionDirPath
<< " looking for packages to be validated";
Result<std::vector<std::string>> scan = FindApexFilesByName(sessionDirPath);
if (!scan.ok()) {
LOG(WARNING) << scan.error();
return scan.error();
}
if (scan->size() > 1) {
return Errorf(
"More than one APEX package found in the same session directory.");
}
auto verified = verifyPackages(*scan, VerifyPackageInstall);
if (!verified.ok()) {
return verified.error();
}
return std::move((*verified)[0]);
}
Result<void> ClearSessions() {
auto sessions = ApexSession::GetSessions();
int cnt = 0;
for (ApexSession& session : sessions) {
Result<void> result = session.DeleteSession();
if (!result.ok()) {
return result;
}
cnt++;
}
if (cnt > 0) {
LOG(DEBUG) << "Deleted " << cnt << " sessions";
}
return {};
}
Result<void> DeleteBackup() {
auto exists = PathExists(std::string(kApexBackupDir));
if (!exists.ok()) {
return Error() << "Can't clean " << kApexBackupDir << " : "
<< exists.error();
}
if (!*exists) {
LOG(DEBUG) << kApexBackupDir << " does not exist. Nothing to clean";
return {};
}
return DeleteDirContent(std::string(kApexBackupDir));
}
Result<void> BackupActivePackages() {
LOG(DEBUG) << "Initializing backup of " << kActiveApexPackagesDataDir;
// Previous restore might've delete backups folder.
auto create_status = createDirIfNeeded(kApexBackupDir, 0700);
if (!create_status.ok()) {
return Error() << "Backup failed : " << create_status.error();
}
auto apex_active_exists = PathExists(std::string(kActiveApexPackagesDataDir));
if (!apex_active_exists.ok()) {
return Error() << "Backup failed : " << apex_active_exists.error();
}
if (!*apex_active_exists) {
LOG(DEBUG) << kActiveApexPackagesDataDir
<< " does not exist. Nothing to backup";
return {};
}
auto active_packages = FindApexFilesByName(kActiveApexPackagesDataDir);
if (!active_packages.ok()) {
return Error() << "Backup failed : " << active_packages.error();
}
auto cleanup_status = DeleteBackup();
if (!cleanup_status.ok()) {
return Error() << "Backup failed : " << cleanup_status.error();
}
auto backup_path_fn = [](const ApexFile& apex_file) {
return StringPrintf("%s/%s%s", kApexBackupDir,
GetPackageId(apex_file.GetManifest()).c_str(),
kApexPackageSuffix);
};
auto deleter = []() {
auto result = DeleteDirContent(std::string(kApexBackupDir));
if (!result.ok()) {
LOG(ERROR) << "Failed to cleanup " << kApexBackupDir << " : "
<< result.error();
}
};
auto scope_guard = android::base::make_scope_guard(deleter);
for (const std::string& path : *active_packages) {
Result<ApexFile> apex_file = ApexFile::Open(path);
if (!apex_file.ok()) {
return Error() << "Backup failed : " << apex_file.error();
}
const auto& dest_path = backup_path_fn(*apex_file);
if (link(apex_file->GetPath().c_str(), dest_path.c_str()) != 0) {
return ErrnoError() << "Failed to backup " << apex_file->GetPath();
}
}
scope_guard.Disable(); // Accept the backup.
return {};
}
Result<void> DoRollback(ApexSession& session) {
if (gInFsCheckpointMode) {
// We will roll back automatically when we reboot
return {};
}
auto scope_guard = android::base::make_scope_guard([&]() {
auto st = session.UpdateStateAndCommit(SessionState::ROLLBACK_FAILED);
LOG(DEBUG) << "Marking " << session << " as failed to rollback";
if (!st.ok()) {
LOG(WARNING) << "Failed to mark session " << session
<< " as failed to rollback : " << st.error();
}
});
auto backup_exists = PathExists(std::string(kApexBackupDir));
if (!backup_exists.ok()) {
return backup_exists.error();
}
if (!*backup_exists) {
return Error() << kApexBackupDir << " does not exist";
}
struct stat stat_data;
if (stat(kActiveApexPackagesDataDir, &stat_data) != 0) {
return ErrnoError() << "Failed to access " << kActiveApexPackagesDataDir;
}
LOG(DEBUG) << "Deleting existing packages in " << kActiveApexPackagesDataDir;
auto delete_status =
DeleteDirContent(std::string(kActiveApexPackagesDataDir));
if (!delete_status.ok()) {
return delete_status;
}
LOG(DEBUG) << "Renaming " << kApexBackupDir << " to "
<< kActiveApexPackagesDataDir;
if (rename(kApexBackupDir, kActiveApexPackagesDataDir) != 0) {
return ErrnoError() << "Failed to rename " << kApexBackupDir << " to "
<< kActiveApexPackagesDataDir;
}
LOG(DEBUG) << "Restoring original permissions for "
<< kActiveApexPackagesDataDir;
if (chmod(kActiveApexPackagesDataDir, stat_data.st_mode & ALLPERMS) != 0) {
// TODO: should we wipe out /data/apex/active if chmod fails?
return ErrnoError() << "Failed to restore original permissions for "
<< kActiveApexPackagesDataDir;
}
scope_guard.Disable(); // Rollback succeeded. Accept state.
return {};
}
Result<void> RollbackStagedSession(ApexSession& session) {
// If the session is staged, it hasn't been activated yet, and we just need
// to update its state to prevent it from being activated later.
return session.UpdateStateAndCommit(SessionState::ROLLED_BACK);
}
Result<void> RollbackActivatedSession(ApexSession& session) {
if (gInFsCheckpointMode) {
LOG(DEBUG) << "Checkpoint mode is enabled";
// On checkpointing devices, our modifications on /data will be
// automatically rolled back when we abort changes. Updating the session
// state is pointless here, as it will be rolled back as well.
return {};
}
auto status =
session.UpdateStateAndCommit(SessionState::ROLLBACK_IN_PROGRESS);
if (!status.ok()) {
// TODO: should we continue with a rollback?
return Error() << "Rollback of session " << session
<< " failed : " << status.error();
}
status = DoRollback(session);
if (!status.ok()) {
return Error() << "Rollback of session " << session
<< " failed : " << status.error();
}
status = session.UpdateStateAndCommit(SessionState::ROLLED_BACK);
if (!status.ok()) {
LOG(WARNING) << "Failed to mark session " << session
<< " as rolled back : " << status.error();
}
return {};
}
Result<void> RollbackSession(ApexSession& session) {
LOG(DEBUG) << "Initializing rollback of " << session;
switch (session.GetState()) {
case SessionState::ROLLBACK_IN_PROGRESS:
[[clang::fallthrough]];
case SessionState::ROLLED_BACK:
return {};
case SessionState::STAGED:
return RollbackStagedSession(session);
case SessionState::ACTIVATED:
return RollbackActivatedSession(session);
default:
return Error() << "Can't restore session " << session
<< " : session is in a wrong state";
}
}
Result<void> ResumeRollback(ApexSession& session) {
auto backup_exists = PathExists(std::string(kApexBackupDir));
if (!backup_exists.ok()) {
return backup_exists.error();
}
if (*backup_exists) {
auto rollback_status = DoRollback(session);
if (!rollback_status.ok()) {
return rollback_status;
}
}
auto status = session.UpdateStateAndCommit(SessionState::ROLLED_BACK);
if (!status.ok()) {
LOG(WARNING) << "Failed to mark session " << session
<< " as rolled back : " << status.error();
}
return {};
}
Result<void> UnmountPackage(const ApexFile& apex, bool allow_latest) {
LOG(VERBOSE) << "Unmounting " << GetPackageId(apex.GetManifest());
const ApexManifest& manifest = apex.GetManifest();
std::optional<MountedApexData> data;
bool latest = false;
auto fn = [&](const MountedApexData& d, bool l) {
if (d.full_path == apex.GetPath()) {
data.emplace(d);
latest = l;
}
};
gMountedApexes.ForallMountedApexes(manifest.name(), fn);
if (!data) {
return Error() << "Did not find " << apex.GetPath();
}
if (latest) {
if (!allow_latest) {
return Error() << "Package " << apex.GetPath() << " is active";
}
std::string mount_point = apexd_private::GetActiveMountPoint(manifest);
LOG(VERBOSE) << "Unmounting and deleting " << mount_point;
if (umount2(mount_point.c_str(), UMOUNT_NOFOLLOW) != 0) {
return ErrnoError() << "Failed to unmount " << mount_point;
}
if (rmdir(mount_point.c_str()) != 0) {
PLOG(ERROR) << "Could not rmdir " << mount_point;
// Continue here.
}
}
// Clean up gMountedApexes now, even though we're not fully done.
gMountedApexes.RemoveMountedApex(manifest.name(), apex.GetPath());
return Unmount(*data);
}
} // namespace
Result<void> MountPackage(const ApexFile& apex, const std::string& mountPoint) {
auto ret =
MountPackageImpl(apex, mountPoint, GetPackageId(apex.GetManifest()),
GetHashTreeFileName(apex, /* is_new = */ false),
/* verifyImage = */ false);
if (!ret.ok()) {
return ret.error();
}
gMountedApexes.AddMountedApex(apex.GetManifest().name(), false, *ret);
return {};
}
namespace apexd_private {
Result<MountedApexData> TempMountPackage(const ApexFile& apex,
const std::string& mount_point) {
// TODO(ioffe): consolidate these two methods.
return android::apex::VerifyAndTempMountPackage(apex, mount_point);
}
Result<void> Unmount(const MountedApexData& data) {
// TODO(ioffe): consolidate these two methods.
return android::apex::Unmount(data);
}
bool IsMounted(const std::string& name, const std::string& full_path) {
bool found_mounted = false;
gMountedApexes.ForallMountedApexes(
name, [&](const MountedApexData& data, bool latest ATTRIBUTE_UNUSED) {
if (full_path == data.full_path) {
found_mounted = true;
}
});
return found_mounted;
}
std::string GetPackageMountPoint(const ApexManifest& manifest) {
return StringPrintf("%s/%s", kApexRoot, GetPackageId(manifest).c_str());
}
std::string GetPackageTempMountPoint(const ApexManifest& manifest) {
return StringPrintf("%s.tmp", GetPackageMountPoint(manifest).c_str());
}
std::string GetActiveMountPoint(const ApexManifest& manifest) {
return StringPrintf("%s/%s", kApexRoot, manifest.name().c_str());
}
} // namespace apexd_private
Result<void> resumeRollbackIfNeeded() {
auto session = ApexSession::GetActiveSession();
if (!session.ok()) {
return session.error();
}
if (!session->has_value()) {
return {};
}
if ((**session).GetState() == SessionState::ROLLBACK_IN_PROGRESS) {
// This means that phone was rebooted during the rollback. Resuming it.
return ResumeRollback(**session);
}
return {};
}
Result<void> activatePackageImpl(const ApexFile& apex_file) {
const ApexManifest& manifest = apex_file.GetManifest();
if (gBootstrap && !isBootstrapApex(apex_file)) {
LOG(INFO) << "Skipped when bootstrapping";
return {};
}
// See whether we think it's active, and do not allow to activate the same
// version. Also detect whether this is the highest version.
// We roll this into a single check.
bool is_newest_version = true;
bool found_other_version = false;
bool version_found_mounted = false;
{
uint64_t new_version = manifest.version();
bool version_found_active = false;
gMountedApexes.ForallMountedApexes(
manifest.name(), [&](const MountedApexData& data, bool latest) {
Result<ApexFile> otherApex = ApexFile::Open(data.full_path);
if (!otherApex.ok()) {
return;
}
found_other_version = true;
if (static_cast<uint64_t>(otherApex->GetManifest().version()) ==
new_version) {
version_found_mounted = true;
version_found_active = latest;
}
if (static_cast<uint64_t>(otherApex->GetManifest().version()) >
new_version) {
is_newest_version = false;
}
});
if (version_found_active) {
LOG(DEBUG) << "Package " << manifest.name() << " with version "
<< manifest.version() << " already active";
return {};
}
}
const std::string& mountPoint = apexd_private::GetPackageMountPoint(manifest);
if (!version_found_mounted) {
auto mountStatus = MountPackage(apex_file, mountPoint);
if (!mountStatus.ok()) {
return mountStatus;
}
}
bool mounted_latest = false;
if (is_newest_version) {
const Result<void>& update_st = apexd_private::BindMount(
apexd_private::GetActiveMountPoint(manifest), mountPoint);
mounted_latest = update_st.has_value();
if (!update_st.ok()) {
return Error() << "Failed to update package " << manifest.name()
<< " to version " << manifest.version() << " : "
<< update_st.error();
}
}
if (mounted_latest) {
gMountedApexes.SetLatest(manifest.name(), apex_file.GetPath());
}
LOG(DEBUG) << "Successfully activated " << apex_file.GetPath()
<< " package_name: " << manifest.name()
<< " version: " << manifest.version();
return {};
}
Result<void> activatePackage(const std::string& full_path) {
LOG(INFO) << "Trying to activate " << full_path;
Result<ApexFile> apex_file = ApexFile::Open(full_path);
if (!apex_file.ok()) {
return apex_file.error();
}
return activatePackageImpl(*apex_file);
}
Result<void> deactivatePackage(const std::string& full_path) {
LOG(INFO) << "Trying to deactivate " << full_path;
Result<ApexFile> apexFile = ApexFile::Open(full_path);
if (!apexFile.ok()) {
return apexFile.error();
}
return UnmountPackage(*apexFile, /* allow_latest= */ true);
}
std::vector<ApexFile> getActivePackages() {
std::vector<ApexFile> ret;
gMountedApexes.ForallMountedApexes(
[&](const std::string&, const MountedApexData& data, bool latest) {
if (!latest) {
return;
}
Result<ApexFile> apexFile = ApexFile::Open(data.full_path);
if (!apexFile.ok()) {
// TODO: Fail?
return;
}
ret.emplace_back(std::move(*apexFile));
});
return ret;
}
namespace {
std::unordered_map<std::string, uint64_t> GetActivePackagesMap() {
std::vector<ApexFile> active_packages = getActivePackages();
std::unordered_map<std::string, uint64_t> ret;
for (const auto& package : active_packages) {
const ApexManifest& manifest = package.GetManifest();
ret.insert({manifest.name(), manifest.version()});
}
return ret;
}
} // namespace
std::vector<ApexFile> getFactoryPackages() {
std::vector<ApexFile> ret;
for (const auto& dir : kApexPackageBuiltinDirs) {
auto apex_files = FindApexFilesByName(dir);
if (!apex_files.ok()) {
LOG(ERROR) << apex_files.error();
continue;
}
for (const std::string& path : *apex_files) {
Result<ApexFile> apex_file = ApexFile::Open(path);
if (!apex_file.ok()) {
LOG(ERROR) << apex_file.error();
} else {
ret.emplace_back(std::move(*apex_file));
}
}
}
return ret;
}
Result<ApexFile> getActivePackage(const std::string& packageName) {
std::vector<ApexFile> packages = getActivePackages();
for (ApexFile& apex : packages) {
if (apex.GetManifest().name() == packageName) {
return std::move(apex);
}
}
return ErrnoError() << "Cannot find matching package for: " << packageName;
}
Result<void> abortActiveSession() {
auto session_or_none = ApexSession::GetActiveSession();
if (!session_or_none.ok()) {
return session_or_none.error();
}
if (session_or_none->has_value()) {
auto& session = session_or_none->value();
LOG(DEBUG) << "Aborting active session " << session;
switch (session.GetState()) {
case SessionState::VERIFIED:
[[clang::fallthrough]];
case SessionState::STAGED:
return session.DeleteSession();
case SessionState::ACTIVATED:
return RollbackActivatedSession(session);
default:
return Error() << "Session " << session << " can't be aborted";
}
} else {
LOG(DEBUG) << "There are no active sessions";
return {};
}
}
// TODO(ioffe): cleanup activation logic to avoid unnecessary scanning.
namespace {
Result<std::vector<ApexFile>> ScanApexFiles(const char* apex_package_dir) {
LOG(INFO) << "Scanning " << apex_package_dir << " looking for APEX packages.";
if (access(apex_package_dir, F_OK) != 0 && errno == ENOENT) {
LOG(INFO) << "... does not exist. Skipping";
return {};
}
Result<std::vector<std::string>> scan = FindApexFilesByName(apex_package_dir);
if (!scan.ok()) {
return Error() << "Failed to scan " << apex_package_dir << " : "
<< scan.error();
}
std::vector<ApexFile> ret;
for (const auto& name : *scan) {
LOG(INFO) << "Found " << name;
Result<ApexFile> apex_file = ApexFile::Open(name);
if (!apex_file.ok()) {
LOG(ERROR) << "Failed to scan " << name << " : " << apex_file.error();
} else {
ret.emplace_back(std::move(*apex_file));
}
}
return ret;
}
Result<void> ActivateApexPackages(const std::vector<ApexFile>& apexes) {
const auto& packages_with_code = GetActivePackagesMap();
size_t failed_cnt = 0;
size_t skipped_cnt = 0;
size_t activated_cnt = 0;
for (const auto& apex : apexes) {
uint64_t new_version = static_cast<uint64_t>(apex.GetManifest().version());
const auto& it = packages_with_code.find(apex.GetManifest().name());
if (it != packages_with_code.end() && it->second >= new_version) {
LOG(INFO) << "Skipping activation of " << apex.GetPath()
<< " same package with higher version " << it->second
<< " is already active";
skipped_cnt++;
continue;
}
if (auto res = activatePackageImpl(apex); !res.ok()) {
LOG(ERROR) << "Failed to activate " << apex.GetPath() << " : "
<< res.error();
failed_cnt++;
} else {
activated_cnt++;
}
}
if (failed_cnt > 0) {
return Error() << "Failed to activate " << failed_cnt << " APEX packages";
}
LOG(INFO) << "Activated " << activated_cnt
<< " packages. Skipped: " << skipped_cnt;
return {};
}
} // namespace
Result<void> scanPackagesDirAndActivate(const char* apex_package_dir) {
auto apexes = ScanApexFiles(apex_package_dir);
if (!apexes.ok()) {
return apexes.error();
}
return ActivateApexPackages(*apexes);
}
/**
* Snapshots data from base_dir/apexdata/<apex name> to
* base_dir/apexrollback/<rollback id>/<apex name>.
*/
Result<void> snapshotDataDirectory(const std::string& base_dir,
const int rollback_id,
const std::string& apex_name) {
auto rollback_path = StringPrintf("%s/%s/%d", base_dir.c_str(),
kApexSnapshotSubDir, rollback_id);
const Result<void> result = createDirIfNeeded(rollback_path, 0700);
if (!result.ok()) {
return Error() << "Failed to create snapshot directory for rollback "
<< rollback_id << " : " << result.error();
}
auto from_path = StringPrintf("%s/%s/%s", base_dir.c_str(), kApexDataSubDir,
apex_name.c_str());
auto to_path =
StringPrintf("%s/%s", rollback_path.c_str(), apex_name.c_str());
return ReplaceFiles(from_path, to_path);
}
/**
* Restores snapshot from base_dir/apexrollback/<rollback id>/<apex name>
* to base_dir/apexdata/<apex name>.
*/
Result<void> restoreDataDirectory(const std::string& base_dir,
const int rollback_id,
const std::string& apex_name) {
auto from_path =
StringPrintf("%s/%s/%d/%s", base_dir.c_str(), kApexSnapshotSubDir,
rollback_id, apex_name.c_str());
auto to_path = StringPrintf("%s/%s/%s", base_dir.c_str(), kApexDataSubDir,
apex_name.c_str());
return ReplaceFiles(from_path, to_path);
}
void snapshotOrRestoreIfNeeded(const std::string& base_dir,
const ApexSession& session) {
if (session.HasRollbackEnabled()) {
for (const auto& apex_name : session.GetApexNames()) {
Result<void> result =
snapshotDataDirectory(base_dir, session.GetRollbackId(), apex_name);
if (!result.ok()) {
LOG(ERROR) << "Snapshot failed for " << apex_name << ": "
<< result.error();
}
}
} else if (session.IsRollback()) {
for (const auto& apex_name : session.GetApexNames()) {
// TODO: Back up existing files in case rollback is reverted.
Result<void> result =
restoreDataDirectory(base_dir, session.GetRollbackId(), apex_name);
if (!result.ok()) {
LOG(ERROR) << "Restore of data failed for " << apex_name << ": "
<< result.error();
}
}
}
}
int snapshotOrRestoreDeUserData() {
auto filter_fn = [](const std::filesystem::directory_entry& entry) {
std::error_code ec;
bool result = entry.is_directory(ec);
if (ec) {
LOG(ERROR) << "Failed to check is_directory : " << ec.message();
return false;
}
return result;
};
auto user_dirs = ReadDir(kDeNDataDir, filter_fn);
if (!user_dirs.ok()) {
LOG(ERROR) << "Error reading dirs " << user_dirs.error();
return 1;
}
auto sessions = ApexSession::GetSessionsInState(SessionState::ACTIVATED);
for (const ApexSession& session : sessions) {
for (const auto& user_dir : *user_dirs) {
snapshotOrRestoreIfNeeded(user_dir, session);
}
}
return 0;
}
Result<ino_t> snapshotCeData(const int user_id, const int rollback_id,
const std::string& apex_name) {
auto base_dir = StringPrintf("%s/%d", kCeDataDir, user_id);
Result<void> result = snapshotDataDirectory(base_dir, rollback_id, apex_name);
if (!result.ok()) {
return result.error();
}
auto ce_snapshot_path =
StringPrintf("%s/%s/%d/%s", base_dir.c_str(), kApexSnapshotSubDir,
rollback_id, apex_name.c_str());
return get_path_inode(ce_snapshot_path);
}
Result<void> restoreCeData(const int user_id, const int rollback_id,
const std::string& apex_name) {
auto base_dir = StringPrintf("%s/%d", kCeDataDir, user_id);
return restoreDataDirectory(base_dir, rollback_id, apex_name);
}
// Migrates sessions directory from /data/apex/sessions to
// /metadata/apex/sessions, if necessary.
Result<void> migrateSessionsDirIfNeeded() {
namespace fs = std::filesystem;
auto from_path = std::string(kApexDataDir) + "/sessions";
auto exists = PathExists(from_path);
if (!exists.ok()) {
return Error() << "Failed to access " << from_path << ": "
<< exists.error();
}
if (!*exists) {
LOG(DEBUG) << from_path << " does not exist. Nothing to migrate.";
return {};
}
auto to_path = kApexSessionsDir;
std::error_code error_code;
fs::copy(from_path, to_path, fs::copy_options::recursive, error_code);
if (error_code) {
return Error() << "Failed to copy old sessions directory"
<< error_code.message();
}
fs::remove_all(from_path, error_code);
if (error_code) {
return Error() << "Failed to delete old sessions directory "
<< error_code.message();
}
return {};
}
void scanStagedSessionsDirAndStage() {
LOG(INFO) << "Scanning " << kApexSessionsDir
<< " looking for sessions to be activated.";
auto stagedSessions = ApexSession::GetSessionsInState(SessionState::STAGED);
for (auto& session : stagedSessions) {
auto sessionId = session.GetId();
auto session_failed_fn = [&]() {
LOG(WARNING) << "Marking session " << sessionId << " as failed.";
auto st = session.UpdateStateAndCommit(SessionState::ACTIVATION_FAILED);
if (!st.ok()) {
LOG(WARNING) << "Failed to mark session " << sessionId
<< " as failed : " << st.error();
}
};
auto scope_guard = android::base::make_scope_guard(session_failed_fn);
std::string build_fingerprint = GetProperty(kBuildFingerprintSysprop, "");
if (session.GetBuildFingerprint().compare(build_fingerprint) != 0) {
LOG(ERROR) << "APEX build fingerprint has changed";
continue;
}
std::vector<std::string> dirsToScan;
if (session.GetChildSessionIds().empty()) {
dirsToScan.push_back(std::string(kStagedSessionsDir) + "/session_" +
std::to_string(sessionId));
} else {
for (auto childSessionId : session.GetChildSessionIds()) {
dirsToScan.push_back(std::string(kStagedSessionsDir) + "/session_" +
std::to_string(childSessionId));
}
}
std::vector<std::string> apexes;
bool scanSuccessful = true;
for (const auto& dirToScan : dirsToScan) {
Result<std::vector<std::string>> scan = FindApexFilesByName(dirToScan);
if (!scan.ok()) {
LOG(WARNING) << scan.error();
scanSuccessful = false;
break;
}
if (scan->size() > 1) {
LOG(WARNING) << "More than one APEX package found in the same session "
<< "directory " << dirToScan << ", skipping activation.";
scanSuccessful = false;
break;
}
if (scan->empty()) {
LOG(WARNING) << "No APEX packages found while scanning " << dirToScan
<< " session id: " << sessionId << ".";
scanSuccessful = false;
break;
}
apexes.push_back(std::move((*scan)[0]));
}
if (!scanSuccessful) {
continue;
}
// Run postinstall, if necessary.
Result<void> postinstall_status = postinstallPackages(apexes);
if (!postinstall_status.ok()) {
LOG(ERROR) << "Postinstall failed for session "
<< std::to_string(sessionId) << ": "
<< postinstall_status.error();
continue;
}
for (const auto& apex : apexes) {
// TODO: Avoid opening ApexFile repeatedly.
Result<ApexFile> apex_file = ApexFile::Open(apex);
if (!apex_file.ok()) {
LOG(ERROR) << "Cannot open apex file during staging: " << apex;
continue;
}
session.AddApexName(apex_file->GetManifest().name());
}
snapshotOrRestoreIfNeeded(kDeSysDataDir, session);
const Result<void> result = stagePackages(apexes);
if (!result.ok()) {
LOG(ERROR) << "Activation failed for packages " << Join(apexes, ',')
<< ": " << result.error();
continue;
}
// Session was OK, release scopeguard.
scope_guard.Disable();
auto st = session.UpdateStateAndCommit(SessionState::ACTIVATED);
if (!st.ok()) {
LOG(ERROR) << "Failed to mark " << session
<< " as activated : " << st.error();
}
}
}
Result<void> preinstallPackages(const std::vector<std::string>& paths) {
if (paths.empty()) {
return Errorf("Empty set of inputs");
}
LOG(DEBUG) << "preinstallPackages() for " << Join(paths, ',');
return HandlePackages<Result<void>>(paths, PreinstallPackages);
}
Result<void> postinstallPackages(const std::vector<std::string>& paths) {
if (paths.empty()) {
return Errorf("Empty set of inputs");
}
LOG(DEBUG) << "postinstallPackages() for " << Join(paths, ',');
return HandlePackages<Result<void>>(paths, PostinstallPackages);
}
namespace {
std::string StageDestPath(const ApexFile& apex_file) {
return StringPrintf("%s/%s%s", kActiveApexPackagesDataDir,
GetPackageId(apex_file.GetManifest()).c_str(),
kApexPackageSuffix);
}
} // namespace
Result<void> stagePackages(const std::vector<std::string>& tmpPaths) {
if (tmpPaths.empty()) {
return Errorf("Empty set of inputs");
}
LOG(DEBUG) << "stagePackages() for " << Join(tmpPaths, ',');
// Note: this function is temporary. As such the code is not optimized, e.g.,
// it will open ApexFiles multiple times.
// 1) Verify all packages.
auto verify_status = verifyPackages(tmpPaths, VerifyPackageBoot);
if (!verify_status.ok()) {
return verify_status.error();
}
// Make sure that kActiveApexPackagesDataDir exists.
auto create_dir_status =
createDirIfNeeded(std::string(kActiveApexPackagesDataDir), 0750);
if (!create_dir_status.ok()) {
return create_dir_status.error();
}
// 2) Now stage all of them.
// Ensure the APEX gets removed on failure.
std::unordered_set<std::string> staged_files;
std::vector<std::string> changed_hashtree_files;
auto deleter = [&staged_files, &changed_hashtree_files]() {
for (const std::string& staged_path : staged_files) {
if (TEMP_FAILURE_RETRY(unlink(staged_path.c_str())) != 0) {
PLOG(ERROR) << "Unable to unlink " << staged_path;
}
}
for (const std::string& hashtree_file : changed_hashtree_files) {
if (TEMP_FAILURE_RETRY(unlink(hashtree_file.c_str())) != 0) {
PLOG(ERROR) << "Unable to unlink " << hashtree_file;
}
}
};
auto scope_guard = android::base::make_scope_guard(deleter);
std::unordered_set<std::string> staged_packages;
for (const std::string& path : tmpPaths) {
Result<ApexFile> apex_file = ApexFile::Open(path);
if (!apex_file.ok()) {
return apex_file.error();
}
// First promote new hashtree file to the one that will be used when
// mounting apex.
std::string new_hashtree_file = GetHashTreeFileName(*apex_file,
/* is_new = */ true);
std::string old_hashtree_file = GetHashTreeFileName(*apex_file,
/* is_new = */ false);
if (access(new_hashtree_file.c_str(), F_OK) == 0) {
if (TEMP_FAILURE_RETRY(rename(new_hashtree_file.c_str(),
old_hashtree_file.c_str())) != 0) {
return ErrnoError() << "Failed to move " << new_hashtree_file << " to "
<< old_hashtree_file;
}
changed_hashtree_files.emplace_back(std::move(old_hashtree_file));
}
// And only then move apex to /data/apex/active.
std::string dest_path = StageDestPath(*apex_file);
if (access(dest_path.c_str(), F_OK) == 0) {
LOG(DEBUG) << dest_path << " already exists. Deleting";
if (TEMP_FAILURE_RETRY(unlink(dest_path.c_str())) != 0) {
return ErrnoError() << "Failed to unlink " << dest_path;
}
}
if (link(apex_file->GetPath().c_str(), dest_path.c_str()) != 0) {
// TODO: Get correct binder error status.
return ErrnoError() << "Unable to link " << apex_file->GetPath() << " to "
<< dest_path;
}
staged_files.insert(dest_path);
staged_packages.insert(apex_file->GetManifest().name());
LOG(DEBUG) << "Success linking " << apex_file->GetPath() << " to "
<< dest_path;
}
scope_guard.Disable(); // Accept the state.
return RemovePreviouslyActiveApexFiles(staged_packages, staged_files);
}
Result<void> unstagePackages(const std::vector<std::string>& paths) {
if (paths.empty()) {
return Errorf("Empty set of inputs");
}
LOG(DEBUG) << "unstagePackages() for " << Join(paths, ',');
// TODO: to make unstage safer, we can copy to be unstaged packages to a
// temporary folder and restore state from it in case unstagePackages fails.
for (const std::string& path : paths) {
if (access(path.c_str(), F_OK) != 0) {
return ErrnoError() << "Can't access " << path;
}
}
for (const std::string& path : paths) {
if (unlink(path.c_str()) != 0) {
return ErrnoError() << "Can't unlink " << path;
}
}
return {};
}
Result<void> rollbackStagedSessionIfAny() {
auto session = ApexSession::GetActiveSession();
if (!session.ok()) {
return session.error();
}
if (!session->has_value()) {
LOG(WARNING) << "No session to rollback";
return {};
}
if ((*session)->GetState() == SessionState::STAGED) {
LOG(INFO) << "Rolling back session " << **session;
return RollbackStagedSession(**session);
}
return Error() << "Can't rollback " << **session
<< " because it is not in STAGED state";
}
Result<void> rollbackActiveSession(const std::string& crashing_native_process) {
auto session = ApexSession::GetActiveSession();
if (!session.ok()) {
return Error() << "Failed to get active session : " << session.error();
} else if (!session->has_value()) {
return Error() << "Rollback requested, when there are no active sessions.";
} else {
if (!crashing_native_process.empty()) {
(*session)->SetCrashingNativeProcess(crashing_native_process);
}
return RollbackSession(*(*session));
}
}
Result<void> rollbackActiveSessionAndReboot(
const std::string& crashing_native_process) {
auto status = rollbackActiveSession(crashing_native_process);
if (!status.ok()) {
return status;
}
LOG(ERROR) << "Successfully rolled back. Time to reboot device.";
if (gInFsCheckpointMode) {
Result<void> res = gVoldService->AbortChanges(
"apexd_initiated" /* message */, false /* retry */);
if (!res.ok()) {
LOG(ERROR) << res.error();
}
}
Reboot();
return {};
}
int onBootstrap() {
gBootstrap = true;
Result<void> preAllocate = preAllocateLoopDevices();
if (!preAllocate.ok()) {
LOG(ERROR) << "Failed to pre-allocate loop devices : "
<< preAllocate.error();
}
std::vector<std::string> bootstrap_apex_dirs{kApexPackageSystemDir,
kApexPackageSystemExtDir};
Result<void> status = collectPreinstalledData(bootstrap_apex_dirs);
if (!status.ok()) {
LOG(ERROR) << "Failed to collect APEX keys : " << status.error();
return 1;
}
// Activate built-in APEXes for processes launched before /data is mounted.
for (const auto& dir : bootstrap_apex_dirs) {
auto scan_status = ScanApexFiles(dir.c_str());
if (!scan_status.ok()) {
LOG(ERROR) << "Failed to scan APEX files in " << dir << " : "
<< scan_status.error();
return 1;
}
if (auto ret = ActivateApexPackages(*scan_status); !ret.ok()) {
LOG(ERROR) << "Failed to activate APEX files in " << dir << " : "
<< ret.error();
return 1;
}
}
LOG(INFO) << "Bootstrapping done";
return 0;
}
Result<void> remountApexFile(const std::string& path) {
auto ret = deactivatePackage(path);
if (!ret.ok()) return ret.error();
ret = activatePackage(path);
if (!ret.ok()) return ret.error();
return {};
}
Result<void> monitorBuiltinDirs() {
int fd = inotify_init1(IN_CLOEXEC);
if (fd == -1) {
return ErrnoErrorf("inotify_init failed");
}
std::map<int, std::string> desc_to_dir;
for (const auto& dir : kApexPackageBuiltinDirs) {
int desc = inotify_add_watch(fd, dir.c_str(), IN_CREATE | IN_MODIFY);
if (desc == -1 && errno != ENOENT) {
// don't complain about missing directories like /product/apex
return ErrnoErrorf("failed to add watch on {}", dir);
}
desc_to_dir.emplace(desc, dir);
}
static std::thread th([fd, desc_to_dir]() -> void {
constexpr int num_events = 100;
constexpr size_t average_path_length = 50;
char buffer[num_events *
(sizeof(struct inotify_event) + average_path_length)];
while (true) {
ssize_t length = read(fd, buffer, sizeof(buffer));
if (length < 0) {
PLOG(ERROR) << "failed to read inotify event: " << strerror(errno);
continue;
}
int i = 0;
while (i < length) {
struct inotify_event* e = (struct inotify_event*)&buffer[i];
if (e->len > 0 && (e->mask & (IN_CREATE | IN_MODIFY)) != 0) {
if (desc_to_dir.find(e->wd) == desc_to_dir.end()) {
LOG(ERROR) << "unexpected watch descriptor " << e->wd
<< " for name: " << e->name;
} else {
std::string path = desc_to_dir.at(e->wd) + "/" + e->name;
auto ret = remountApexFile(path);
if (!ret.ok()) {
LOG(ERROR) << ret.error().message();
} else {
LOG(INFO) << path << " remounted because it was changed";
}
}
}
i += sizeof(struct inotify_event) + e->len;
}
}
});
return {};
}
void onStart(CheckpointInterface* checkpoint_service) {
LOG(INFO) << "Marking APEXd as starting";
if (!android::base::SetProperty(kApexStatusSysprop, kApexStatusStarting)) {
PLOG(ERROR) << "Failed to set " << kApexStatusSysprop << " to "
<< kApexStatusStarting;
}
if (checkpoint_service != nullptr) {
gVoldService = checkpoint_service;
Result<bool> supports_fs_checkpoints =
gVoldService->SupportsFsCheckpoints();
if (supports_fs_checkpoints.ok()) {
gSupportsFsCheckpoints = *supports_fs_checkpoints;
} else {
LOG(ERROR) << "Failed to check if filesystem checkpoints are supported: "
<< supports_fs_checkpoints.error();
}
if (gSupportsFsCheckpoints) {
Result<bool> needs_checkpoint = gVoldService->NeedsCheckpoint();
if (needs_checkpoint.ok()) {
gInFsCheckpointMode = *needs_checkpoint;
} else {
LOG(ERROR) << "Failed to check if we're in filesystem checkpoint mode: "
<< needs_checkpoint.error();
}
}
}
// Ask whether we should roll back any staged sessions; this can happen if
// we've exceeded the retry count on a device that supports filesystem
// checkpointing.
if (gSupportsFsCheckpoints) {
Result<bool> needs_rollback = gVoldService->NeedsRollback();
if (!needs_rollback.ok()) {
LOG(ERROR) << "Failed to check if we need a rollback: "
<< needs_rollback.error();
} else if (*needs_rollback) {
LOG(INFO) << "Exceeded number of session retries ("
<< kNumRetriesWhenCheckpointingEnabled
<< "). Starting a rollback";
Result<void> status = rollbackStagedSessionIfAny();
if (!status.ok()) {
LOG(ERROR)
<< "Failed to roll back (as requested by fs checkpointing) : "
<< status.error();
}
}
}
Result<void> status = collectPreinstalledData(kApexPackageBuiltinDirs);
if (!status.ok()) {
LOG(ERROR) << "Failed to collect APEX keys : " << status.error();
return;
}
gMountedApexes.PopulateFromMounts();
// Activate APEXes from /data/apex. If one in the directory is newer than the
// system one, the new one will eclipse the old one.
scanStagedSessionsDirAndStage();
status = resumeRollbackIfNeeded();
if (!status.ok()) {
LOG(ERROR) << "Failed to resume rollback : " << status.error();
}
std::vector<ApexFile> data_apex;
if (auto scan = ScanApexFiles(kActiveApexPackagesDataDir); !scan.ok()) {
LOG(ERROR) << "Failed to scan packages from " << kActiveApexPackagesDataDir
<< " : " << scan.error();
if (auto rollback = rollbackActiveSessionAndReboot(""); !rollback.ok()) {
LOG(ERROR) << "Failed to rollback : " << rollback.error();
}
} else {
// Don't activate orphaned APEX packages that don't have a pre-installed
// version.
auto filter_fn = [](const auto& apex) {
if (HasPreInstalledVersion(apex.GetManifest().name())) {
return true;
}
LOG(WARNING) << "Skipping " << apex.GetPath()
<< " because there is no pre-installed version";
return false;
};
std::copy_if(std::make_move_iterator(scan->begin()),
std::make_move_iterator(scan->end()),
std::back_inserter(data_apex), filter_fn);
}
if (auto ret = ActivateApexPackages(data_apex); !ret.ok()) {
LOG(ERROR) << "Failed to activate packages from "
<< kActiveApexPackagesDataDir << " : " << ret.error();
if (auto rollback = rollbackActiveSessionAndReboot(""); !rollback.ok()) {
LOG(ERROR) << "Failed to rollback : " << rollback.error();
}
}
// Now also scan and activate APEXes from pre-installed directories.
for (const auto& dir : kApexPackageBuiltinDirs) {
auto scan = ScanApexFiles(dir.c_str());
if (!scan.ok()) {
LOG(ERROR) << "Failed to scan APEX packages from " << dir << " : "
<< scan.error();
if (auto rollback = rollbackActiveSessionAndReboot(""); !rollback.ok()) {
LOG(ERROR) << "Failed to rollback : " << rollback.error();
}
}
if (auto activate = ActivateApexPackages(*scan); !activate.ok()) {
// This should never happen. Like **really** never.
// TODO: should we kill apexd in this case?
LOG(ERROR) << "Failed to activate packages from " << dir << " : "
<< activate.error();
}
}
if (android::base::GetBoolProperty("ro.debuggable", false)) {
status = monitorBuiltinDirs();
if (!status.ok()) {
LOG(ERROR) << "cannot monitor built-in dirs: " << status.error();
}
}
}
void onAllPackagesReady() {
// Set a system property to let other components to know that APEXs are
// correctly mounted and ready to be used. Before using any file from APEXs,
// they can query this system property to ensure that they are okay to
// access. Or they may have a on-property trigger to delay a task until
// APEXs become ready.
LOG(INFO) << "Marking APEXd as ready";
if (!android::base::SetProperty(kApexStatusSysprop, kApexStatusReady)) {
PLOG(ERROR) << "Failed to set " << kApexStatusSysprop << " to "
<< kApexStatusReady;
}
}
Result<std::vector<ApexFile>> submitStagedSession(
const int session_id, const std::vector<int>& child_session_ids,
const bool has_rollback_enabled, const bool is_rollback,
const int rollback_id) {
if (session_id == 0) {
return Error() << "Session id was not provided.";
}
bool needsBackup = true;
Result<void> cleanup_status = ClearSessions();
if (!cleanup_status.ok()) {
return cleanup_status.error();
}
if (gSupportsFsCheckpoints) {
Result<void> checkpoint_status =
gVoldService->StartCheckpoint(kNumRetriesWhenCheckpointingEnabled);
if (!checkpoint_status.ok()) {
// The device supports checkpointing, but we could not start it;
// log a warning, but do continue, since we can live without it.
LOG(WARNING) << "Failed to start filesystem checkpoint on device that "
"should support it: "
<< checkpoint_status.error();
} else {
needsBackup = false;
}
}
if (needsBackup) {
Result<void> backup_status = BackupActivePackages();
if (!backup_status.ok()) {
return backup_status.error();
}
}
std::vector<int> ids_to_scan;
if (!child_session_ids.empty()) {
ids_to_scan = child_session_ids;
} else {
ids_to_scan = {session_id};
}
std::vector<ApexFile> ret;
for (int id_to_scan : ids_to_scan) {
auto verified = verifySessionDir(id_to_scan);
if (!verified.ok()) {
return verified.error();
}
ret.push_back(std::move(*verified));
}
// Run preinstall, if necessary.
Result<void> preinstall_status = PreinstallPackages(ret);
if (!preinstall_status.ok()) {
return preinstall_status.error();
}
if (has_rollback_enabled && is_rollback) {
return Error() << "Cannot set session " << session_id << " as both a"
<< " rollback and enabled for rollback.";
}
auto session = ApexSession::CreateSession(session_id);
if (!session.ok()) {
return session.error();
}
(*session).SetChildSessionIds(child_session_ids);
std::string build_fingerprint = GetProperty(kBuildFingerprintSysprop, "");
(*session).SetBuildFingerprint(build_fingerprint);
session->SetHasRollbackEnabled(has_rollback_enabled);
session->SetIsRollback(is_rollback);
session->SetRollbackId(rollback_id);
Result<void> commit_status =
(*session).UpdateStateAndCommit(SessionState::VERIFIED);
if (!commit_status.ok()) {
return commit_status.error();
}
return ret;
}
Result<void> markStagedSessionReady(const int session_id) {
auto session = ApexSession::GetSession(session_id);
if (!session.ok()) {
return session.error();
}
// We should only accept sessions in SessionState::VERIFIED or
// SessionState::STAGED state. In the SessionState::STAGED case, this
// function is effectively a no-op.
auto session_state = (*session).GetState();
if (session_state == SessionState::STAGED) {
return {};
}
if (session_state == SessionState::VERIFIED) {
return (*session).UpdateStateAndCommit(SessionState::STAGED);
}
return Error() << "Invalid state for session " << session_id
<< ". Cannot mark it as ready.";
}
Result<void> markStagedSessionSuccessful(const int session_id) {
auto session = ApexSession::GetSession(session_id);
if (!session.ok()) {
return session.error();
}
// Only SessionState::ACTIVATED or SessionState::SUCCESS states are accepted.
// In the SessionState::SUCCESS state, this function is a no-op.
if (session->GetState() == SessionState::SUCCESS) {
return {};
} else if (session->GetState() == SessionState::ACTIVATED) {
auto cleanup_status = DeleteBackup();
if (!cleanup_status.ok()) {
return Error() << "Failed to mark session " << *session
<< " as successful : " << cleanup_status.error();
}
return session->UpdateStateAndCommit(SessionState::SUCCESS);
} else {
return Error() << "Session " << *session << " can not be marked successful";
}
}
// Find dangling mounts and unmount them.
// If one is on /data/apex/active, remove it.
void unmountDanglingMounts() {
std::multimap<std::string, MountedApexData> danglings;
gMountedApexes.ForallMountedApexes([&](const std::string& package,
const MountedApexData& data,
bool latest) {
if (!latest) {
danglings.insert({package, data});
}
});
for (const auto& [package, data] : danglings) {
const std::string& path = data.full_path;
LOG(VERBOSE) << "Unmounting " << data.mount_point;
gMountedApexes.RemoveMountedApex(package, path);
if (auto st = Unmount(data); !st.ok()) {
LOG(ERROR) << st.error();
}
if (StartsWith(path, kActiveApexPackagesDataDir)) {
LOG(VERBOSE) << "Deleting old APEX " << path;
if (unlink(path.c_str()) != 0) {
PLOG(ERROR) << "Failed to delete " << path;
}
}
}
RemoveObsoleteHashTrees();
}
int unmountAll() {
gMountedApexes.PopulateFromMounts();
int ret = 0;
gMountedApexes.ForallMountedApexes([&](const std::string& /*package*/,
const MountedApexData& data,
bool latest) {
LOG(INFO) << "Unmounting " << data.full_path << " mounted on "
<< data.mount_point;
if (latest) {
auto pos = data.mount_point.find('@');
CHECK(pos != std::string::npos);
std::string bind_mount = data.mount_point.substr(0, pos);
if (umount2(bind_mount.c_str(), UMOUNT_NOFOLLOW) != 0) {
PLOG(ERROR) << "Failed to unmount bind-mount " << bind_mount;
ret = 1;
}
}
if (auto status = Unmount(data); !status.ok()) {
LOG(ERROR) << "Failed to unmount " << data.mount_point << " : "
<< status.error();
ret = 1;
}
});
return ret;
}
} // namespace apex
} // namespace android