3d4fb41f3d
am: 4a625453bf
Change-Id: Idd91865540106b5030f74b26037b61c00719ef28
865 lines
26 KiB
C++
865 lines
26 KiB
C++
/*
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* Copyright (C) 2008 The Android Open Source Project
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#define ATRACE_TAG ATRACE_TAG_PACKAGE_MANAGER
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#include <dirent.h>
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#include <errno.h>
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#include <fcntl.h>
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#include <mntent.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <sys/ioctl.h>
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#include <sys/mount.h>
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#include <sys/stat.h>
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#include <sys/types.h>
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#include <sys/sysmacros.h>
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#include <sys/wait.h>
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#include <unistd.h>
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#include <linux/kdev_t.h>
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#include <android-base/logging.h>
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#include <android-base/parseint.h>
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#include <android-base/properties.h>
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#include <android-base/stringprintf.h>
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#include <android-base/strings.h>
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#include <cutils/fs.h>
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#include <utils/Trace.h>
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#include <selinux/android.h>
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#include <sysutils/NetlinkEvent.h>
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#include <private/android_filesystem_config.h>
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#include <ext4_utils/ext4_crypt.h>
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#include "Devmapper.h"
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#include "Ext4Crypt.h"
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#include "Loop.h"
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#include "NetlinkManager.h"
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#include "Process.h"
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#include "Utils.h"
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#include "VoldUtil.h"
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#include "VolumeManager.h"
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#include "cryptfs.h"
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#include "fs/Ext4.h"
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#include "fs/Vfat.h"
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#include "model/EmulatedVolume.h"
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#include "model/ObbVolume.h"
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using android::base::StringPrintf;
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using android::base::unique_fd;
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static const char* kPathUserMount = "/mnt/user";
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static const char* kPathVirtualDisk = "/data/misc/vold/virtual_disk";
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static const char* kPropVirtualDisk = "persist.sys.virtual_disk";
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/* 512MiB is large enough for testing purposes */
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static const unsigned int kSizeVirtualDisk = 536870912;
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static const unsigned int kMajorBlockMmc = 179;
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static const unsigned int kMajorBlockExperimentalMin = 240;
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static const unsigned int kMajorBlockExperimentalMax = 254;
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VolumeManager *VolumeManager::sInstance = NULL;
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VolumeManager *VolumeManager::Instance() {
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if (!sInstance)
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sInstance = new VolumeManager();
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return sInstance;
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}
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VolumeManager::VolumeManager() {
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mDebug = false;
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mNextObbId = 0;
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// For security reasons, assume that a secure keyguard is
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// showing until we hear otherwise
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mSecureKeyguardShowing = true;
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}
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VolumeManager::~VolumeManager() {
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}
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int VolumeManager::updateVirtualDisk() {
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ATRACE_NAME("VolumeManager::updateVirtualDisk");
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if (android::base::GetBoolProperty(kPropVirtualDisk, false)) {
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if (access(kPathVirtualDisk, F_OK) != 0) {
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Loop::createImageFile(kPathVirtualDisk, kSizeVirtualDisk / 512);
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}
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if (mVirtualDisk == nullptr) {
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if (Loop::create(kPathVirtualDisk, mVirtualDiskPath) != 0) {
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LOG(ERROR) << "Failed to create virtual disk";
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return -1;
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}
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struct stat buf;
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if (stat(mVirtualDiskPath.c_str(), &buf) < 0) {
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PLOG(ERROR) << "Failed to stat " << mVirtualDiskPath;
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return -1;
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}
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auto disk = new android::vold::Disk("virtual", buf.st_rdev, "virtual",
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android::vold::Disk::Flags::kAdoptable | android::vold::Disk::Flags::kSd);
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mVirtualDisk = std::shared_ptr<android::vold::Disk>(disk);
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handleDiskAdded(mVirtualDisk);
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}
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} else {
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if (mVirtualDisk != nullptr) {
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dev_t device = mVirtualDisk->getDevice();
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handleDiskRemoved(device);
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Loop::destroyByDevice(mVirtualDiskPath.c_str());
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mVirtualDisk = nullptr;
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}
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if (access(kPathVirtualDisk, F_OK) == 0) {
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unlink(kPathVirtualDisk);
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}
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}
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return 0;
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}
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int VolumeManager::setDebug(bool enable) {
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mDebug = enable;
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return 0;
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}
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int VolumeManager::start() {
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ATRACE_NAME("VolumeManager::start");
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// Always start from a clean slate by unmounting everything in
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// directories that we own, in case we crashed.
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unmountAll();
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Devmapper::destroyAll();
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Loop::destroyAll();
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// Assume that we always have an emulated volume on internal
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// storage; the framework will decide if it should be mounted.
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CHECK(mInternalEmulated == nullptr);
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mInternalEmulated = std::shared_ptr<android::vold::VolumeBase>(
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new android::vold::EmulatedVolume("/data/media"));
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mInternalEmulated->create();
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// Consider creating a virtual disk
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updateVirtualDisk();
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return 0;
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}
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int VolumeManager::stop() {
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CHECK(mInternalEmulated != nullptr);
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mInternalEmulated->destroy();
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mInternalEmulated = nullptr;
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return 0;
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}
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void VolumeManager::handleBlockEvent(NetlinkEvent *evt) {
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std::lock_guard<std::mutex> lock(mLock);
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if (mDebug) {
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LOG(VERBOSE) << "----------------";
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LOG(VERBOSE) << "handleBlockEvent with action " << (int) evt->getAction();
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evt->dump();
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}
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std::string eventPath(evt->findParam("DEVPATH")?evt->findParam("DEVPATH"):"");
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std::string devType(evt->findParam("DEVTYPE")?evt->findParam("DEVTYPE"):"");
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if (devType != "disk") return;
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int major = std::stoi(evt->findParam("MAJOR"));
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int minor = std::stoi(evt->findParam("MINOR"));
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dev_t device = makedev(major, minor);
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switch (evt->getAction()) {
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case NetlinkEvent::Action::kAdd: {
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for (const auto& source : mDiskSources) {
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if (source->matches(eventPath)) {
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// For now, assume that MMC and virtio-blk (the latter is
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// emulator-specific; see Disk.cpp for details) devices are SD,
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// and that everything else is USB
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int flags = source->getFlags();
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if (major == kMajorBlockMmc
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|| (android::vold::IsRunningInEmulator()
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&& major >= (int) kMajorBlockExperimentalMin
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&& major <= (int) kMajorBlockExperimentalMax)) {
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flags |= android::vold::Disk::Flags::kSd;
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} else {
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flags |= android::vold::Disk::Flags::kUsb;
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}
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auto disk = new android::vold::Disk(eventPath, device,
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source->getNickname(), flags);
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handleDiskAdded(std::shared_ptr<android::vold::Disk>(disk));
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break;
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}
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}
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break;
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}
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case NetlinkEvent::Action::kChange: {
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LOG(DEBUG) << "Disk at " << major << ":" << minor << " changed";
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handleDiskChanged(device);
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break;
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}
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case NetlinkEvent::Action::kRemove: {
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handleDiskRemoved(device);
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break;
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}
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default: {
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LOG(WARNING) << "Unexpected block event action " << (int) evt->getAction();
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break;
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}
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}
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}
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void VolumeManager::handleDiskAdded(const std::shared_ptr<android::vold::Disk>& disk) {
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// For security reasons, if secure keyguard is showing, wait
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// until the user unlocks the device to actually touch it
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if (mSecureKeyguardShowing) {
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LOG(INFO) << "Found disk at " << disk->getEventPath()
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<< " but delaying scan due to secure keyguard";
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mPendingDisks.push_back(disk);
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} else {
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disk->create();
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mDisks.push_back(disk);
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}
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}
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void VolumeManager::handleDiskChanged(dev_t device) {
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for (const auto& disk : mDisks) {
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if (disk->getDevice() == device) {
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disk->readMetadata();
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disk->readPartitions();
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}
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}
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// For security reasons, we ignore all pending disks, since
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// we'll scan them once the device is unlocked
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}
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void VolumeManager::handleDiskRemoved(dev_t device) {
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auto i = mDisks.begin();
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while (i != mDisks.end()) {
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if ((*i)->getDevice() == device) {
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(*i)->destroy();
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i = mDisks.erase(i);
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} else {
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++i;
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}
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}
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auto j = mPendingDisks.begin();
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while (j != mPendingDisks.end()) {
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if ((*j)->getDevice() == device) {
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j = mPendingDisks.erase(j);
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} else {
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++j;
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}
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}
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}
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void VolumeManager::addDiskSource(const std::shared_ptr<DiskSource>& diskSource) {
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std::lock_guard<std::mutex> lock(mLock);
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mDiskSources.push_back(diskSource);
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}
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std::shared_ptr<android::vold::Disk> VolumeManager::findDisk(const std::string& id) {
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for (auto disk : mDisks) {
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if (disk->getId() == id) {
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return disk;
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}
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}
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return nullptr;
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}
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std::shared_ptr<android::vold::VolumeBase> VolumeManager::findVolume(const std::string& id) {
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// Vold could receive "mount" after "shutdown" command in the extreme case.
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// If this happens, mInternalEmulated will equal nullptr and
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// we need to deal with it in order to avoid null pointer crash.
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if (mInternalEmulated != nullptr && mInternalEmulated->getId() == id) {
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return mInternalEmulated;
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}
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for (const auto& disk : mDisks) {
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auto vol = disk->findVolume(id);
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if (vol != nullptr) {
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return vol;
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}
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}
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for (const auto& vol : mObbVolumes) {
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if (vol->getId() == id) {
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return vol;
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}
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}
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return nullptr;
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}
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void VolumeManager::listVolumes(android::vold::VolumeBase::Type type,
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std::list<std::string>& list) {
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list.clear();
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for (const auto& disk : mDisks) {
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disk->listVolumes(type, list);
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}
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}
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int VolumeManager::forgetPartition(const std::string& partGuid, const std::string& fsUuid) {
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std::string normalizedGuid;
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if (android::vold::NormalizeHex(partGuid, normalizedGuid)) {
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LOG(WARNING) << "Invalid GUID " << partGuid;
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return -1;
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}
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bool success = true;
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std::string keyPath = android::vold::BuildKeyPath(normalizedGuid);
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if (unlink(keyPath.c_str()) != 0) {
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LOG(ERROR) << "Failed to unlink " << keyPath;
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success = false;
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}
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if (e4crypt_is_native()) {
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if (!e4crypt_destroy_volume_keys(fsUuid)) {
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success = false;
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}
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}
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return success ? 0 : -1;
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}
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int VolumeManager::linkPrimary(userid_t userId) {
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std::string source(mPrimary->getPath());
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if (mPrimary->getType() == android::vold::VolumeBase::Type::kEmulated) {
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source = StringPrintf("%s/%d", source.c_str(), userId);
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fs_prepare_dir(source.c_str(), 0755, AID_ROOT, AID_ROOT);
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}
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std::string target(StringPrintf("/mnt/user/%d/primary", userId));
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if (TEMP_FAILURE_RETRY(unlink(target.c_str()))) {
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if (errno != ENOENT) {
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PLOG(WARNING) << "Failed to unlink " << target;
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}
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}
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LOG(DEBUG) << "Linking " << source << " to " << target;
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if (TEMP_FAILURE_RETRY(symlink(source.c_str(), target.c_str()))) {
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PLOG(WARNING) << "Failed to link";
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return -errno;
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}
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return 0;
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}
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int VolumeManager::onUserAdded(userid_t userId, int userSerialNumber) {
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mAddedUsers[userId] = userSerialNumber;
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return 0;
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}
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int VolumeManager::onUserRemoved(userid_t userId) {
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mAddedUsers.erase(userId);
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return 0;
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}
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int VolumeManager::onUserStarted(userid_t userId) {
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// Note that sometimes the system will spin up processes from Zygote
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// before actually starting the user, so we're okay if Zygote
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// already created this directory.
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std::string path(StringPrintf("%s/%d", kPathUserMount, userId));
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fs_prepare_dir(path.c_str(), 0755, AID_ROOT, AID_ROOT);
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mStartedUsers.insert(userId);
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if (mPrimary) {
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linkPrimary(userId);
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}
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return 0;
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}
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int VolumeManager::onUserStopped(userid_t userId) {
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mStartedUsers.erase(userId);
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return 0;
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}
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int VolumeManager::onSecureKeyguardStateChanged(bool isShowing) {
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mSecureKeyguardShowing = isShowing;
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if (!mSecureKeyguardShowing) {
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// Now that secure keyguard has been dismissed, process
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// any pending disks
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for (const auto& disk : mPendingDisks) {
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disk->create();
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mDisks.push_back(disk);
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}
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mPendingDisks.clear();
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}
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return 0;
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}
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int VolumeManager::setPrimary(const std::shared_ptr<android::vold::VolumeBase>& vol) {
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mPrimary = vol;
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for (userid_t userId : mStartedUsers) {
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linkPrimary(userId);
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}
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return 0;
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}
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static int unmount_tree(const std::string& prefix) {
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FILE* fp = setmntent("/proc/mounts", "r");
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if (fp == NULL) {
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PLOG(ERROR) << "Failed to open /proc/mounts";
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return -errno;
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}
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// Some volumes can be stacked on each other, so force unmount in
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// reverse order to give us the best chance of success.
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std::list<std::string> toUnmount;
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mntent* mentry;
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while ((mentry = getmntent(fp)) != NULL) {
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auto test = std::string(mentry->mnt_dir) + "/";
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if (android::base::StartsWith(test, prefix)) {
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toUnmount.push_front(test);
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}
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}
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endmntent(fp);
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for (const auto& path : toUnmount) {
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if (umount2(path.c_str(), MNT_DETACH)) {
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PLOG(ERROR) << "Failed to unmount " << path;
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}
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}
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return 0;
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}
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int VolumeManager::remountUid(uid_t uid, const std::string& mode) {
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LOG(DEBUG) << "Remounting " << uid << " as mode " << mode;
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DIR* dir;
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struct dirent* de;
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std::string rootName;
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std::string pidName;
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int pidFd;
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int nsFd;
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struct stat sb;
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pid_t child;
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if (!(dir = opendir("/proc"))) {
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PLOG(ERROR) << "Failed to opendir";
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return -1;
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}
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// Figure out root namespace to compare against below
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if (!android::vold::Readlinkat(dirfd(dir), "1/ns/mnt", &rootName)) {
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PLOG(ERROR) << "Failed to read root namespace";
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closedir(dir);
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return -1;
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}
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// Poke through all running PIDs look for apps running as UID
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while ((de = readdir(dir))) {
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pid_t pid;
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if (de->d_type != DT_DIR) continue;
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if (!android::base::ParseInt(de->d_name, &pid)) continue;
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pidFd = -1;
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nsFd = -1;
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pidFd = openat(dirfd(dir), de->d_name, O_RDONLY | O_DIRECTORY | O_CLOEXEC);
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if (pidFd < 0) {
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goto next;
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}
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if (fstat(pidFd, &sb) != 0) {
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PLOG(WARNING) << "Failed to stat " << de->d_name;
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goto next;
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}
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if (sb.st_uid != uid) {
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goto next;
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}
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// Matches so far, but refuse to touch if in root namespace
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LOG(DEBUG) << "Found matching PID " << de->d_name;
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if (!android::vold::Readlinkat(pidFd, "ns/mnt", &pidName)) {
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PLOG(WARNING) << "Failed to read namespace for " << de->d_name;
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goto next;
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}
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if (rootName == pidName) {
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LOG(WARNING) << "Skipping due to root namespace";
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goto next;
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}
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// We purposefully leave the namespace open across the fork
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nsFd = openat(pidFd, "ns/mnt", O_RDONLY); // not O_CLOEXEC
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if (nsFd < 0) {
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PLOG(WARNING) << "Failed to open namespace for " << de->d_name;
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goto next;
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}
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if (!(child = fork())) {
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if (setns(nsFd, CLONE_NEWNS) != 0) {
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PLOG(ERROR) << "Failed to setns for " << de->d_name;
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_exit(1);
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}
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unmount_tree("/storage/");
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std::string storageSource;
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if (mode == "default") {
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storageSource = "/mnt/runtime/default";
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} else if (mode == "read") {
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storageSource = "/mnt/runtime/read";
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} else if (mode == "write") {
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|
storageSource = "/mnt/runtime/write";
|
|
} else {
|
|
// Sane default of no storage visible
|
|
_exit(0);
|
|
}
|
|
if (TEMP_FAILURE_RETRY(mount(storageSource.c_str(), "/storage",
|
|
NULL, MS_BIND | MS_REC, NULL)) == -1) {
|
|
PLOG(ERROR) << "Failed to mount " << storageSource << " for "
|
|
<< de->d_name;
|
|
_exit(1);
|
|
}
|
|
if (TEMP_FAILURE_RETRY(mount(NULL, "/storage", NULL,
|
|
MS_REC | MS_SLAVE, NULL)) == -1) {
|
|
PLOG(ERROR) << "Failed to set MS_SLAVE to /storage for "
|
|
<< de->d_name;
|
|
_exit(1);
|
|
}
|
|
|
|
// Mount user-specific symlink helper into place
|
|
userid_t user_id = multiuser_get_user_id(uid);
|
|
std::string userSource(StringPrintf("/mnt/user/%d", user_id));
|
|
if (TEMP_FAILURE_RETRY(mount(userSource.c_str(), "/storage/self",
|
|
NULL, MS_BIND, NULL)) == -1) {
|
|
PLOG(ERROR) << "Failed to mount " << userSource << " for "
|
|
<< de->d_name;
|
|
_exit(1);
|
|
}
|
|
|
|
_exit(0);
|
|
}
|
|
|
|
if (child == -1) {
|
|
PLOG(ERROR) << "Failed to fork";
|
|
goto next;
|
|
} else {
|
|
TEMP_FAILURE_RETRY(waitpid(child, nullptr, 0));
|
|
}
|
|
|
|
next:
|
|
close(nsFd);
|
|
close(pidFd);
|
|
}
|
|
closedir(dir);
|
|
return 0;
|
|
}
|
|
|
|
int VolumeManager::reset() {
|
|
// Tear down all existing disks/volumes and start from a blank slate so
|
|
// newly connected framework hears all events.
|
|
if (mInternalEmulated != nullptr) {
|
|
mInternalEmulated->destroy();
|
|
mInternalEmulated->create();
|
|
}
|
|
for (const auto& disk : mDisks) {
|
|
disk->destroy();
|
|
disk->create();
|
|
}
|
|
updateVirtualDisk();
|
|
mAddedUsers.clear();
|
|
mStartedUsers.clear();
|
|
return 0;
|
|
}
|
|
|
|
// Can be called twice (sequentially) during shutdown. should be safe for that.
|
|
int VolumeManager::shutdown() {
|
|
if (mInternalEmulated == nullptr) {
|
|
return 0; // already shutdown
|
|
}
|
|
android::vold::sSleepOnUnmount = false;
|
|
mInternalEmulated->destroy();
|
|
mInternalEmulated = nullptr;
|
|
for (const auto& disk : mDisks) {
|
|
disk->destroy();
|
|
}
|
|
mDisks.clear();
|
|
mPendingDisks.clear();
|
|
android::vold::sSleepOnUnmount = true;
|
|
return 0;
|
|
}
|
|
|
|
int VolumeManager::unmountAll() {
|
|
std::lock_guard<std::mutex> lock(mLock);
|
|
ATRACE_NAME("VolumeManager::unmountAll()");
|
|
|
|
// First, try gracefully unmounting all known devices
|
|
if (mInternalEmulated != nullptr) {
|
|
mInternalEmulated->unmount();
|
|
}
|
|
for (const auto& disk : mDisks) {
|
|
disk->unmountAll();
|
|
}
|
|
|
|
// Worst case we might have some stale mounts lurking around, so
|
|
// force unmount those just to be safe.
|
|
FILE* fp = setmntent("/proc/mounts", "r");
|
|
if (fp == NULL) {
|
|
PLOG(ERROR) << "Failed to open /proc/mounts";
|
|
return -errno;
|
|
}
|
|
|
|
// Some volumes can be stacked on each other, so force unmount in
|
|
// reverse order to give us the best chance of success.
|
|
std::list<std::string> toUnmount;
|
|
mntent* mentry;
|
|
while ((mentry = getmntent(fp)) != NULL) {
|
|
auto test = std::string(mentry->mnt_dir);
|
|
if ((android::base::StartsWith(test, "/mnt/") &&
|
|
!android::base::StartsWith(test, "/mnt/vendor") &&
|
|
!android::base::StartsWith(test, "/mnt/product")) ||
|
|
android::base::StartsWith(test, "/storage/")) {
|
|
toUnmount.push_front(test);
|
|
}
|
|
}
|
|
endmntent(fp);
|
|
|
|
for (const auto& path : toUnmount) {
|
|
LOG(DEBUG) << "Tearing down stale mount " << path;
|
|
android::vold::ForceUnmount(path);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
int VolumeManager::mkdirs(const std::string& path) {
|
|
// Only offer to create directories for paths managed by vold
|
|
if (android::base::StartsWith(path, "/storage/")) {
|
|
// fs_mkdirs() does symlink checking and relative path enforcement
|
|
return fs_mkdirs(path.c_str(), 0700);
|
|
} else {
|
|
LOG(ERROR) << "Failed to find mounted volume for " << path;
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
static size_t kAppFuseMaxMountPointName = 32;
|
|
|
|
static android::status_t getMountPath(uid_t uid, const std::string& name, std::string* path) {
|
|
if (name.size() > kAppFuseMaxMountPointName) {
|
|
LOG(ERROR) << "AppFuse mount name is too long.";
|
|
return -EINVAL;
|
|
}
|
|
for (size_t i = 0; i < name.size(); i++) {
|
|
if (!isalnum(name[i])) {
|
|
LOG(ERROR) << "AppFuse mount name contains invalid character.";
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
*path = android::base::StringPrintf("/mnt/appfuse/%d_%s", uid, name.c_str());
|
|
return android::OK;
|
|
}
|
|
|
|
static android::status_t mountInNamespace(uid_t uid, int device_fd, const std::string& path) {
|
|
// Remove existing mount.
|
|
android::vold::ForceUnmount(path);
|
|
|
|
const auto opts = android::base::StringPrintf(
|
|
"fd=%i,"
|
|
"rootmode=40000,"
|
|
"default_permissions,"
|
|
"allow_other,"
|
|
"user_id=%d,group_id=%d,"
|
|
"context=\"u:object_r:app_fuse_file:s0\","
|
|
"fscontext=u:object_r:app_fusefs:s0",
|
|
device_fd,
|
|
uid,
|
|
uid);
|
|
|
|
const int result = TEMP_FAILURE_RETRY(mount(
|
|
"/dev/fuse", path.c_str(), "fuse",
|
|
MS_NOSUID | MS_NODEV | MS_NOEXEC | MS_NOATIME, opts.c_str()));
|
|
if (result != 0) {
|
|
PLOG(ERROR) << "Failed to mount " << path;
|
|
return -errno;
|
|
}
|
|
|
|
return android::OK;
|
|
}
|
|
|
|
static android::status_t runCommandInNamespace(const std::string& command,
|
|
uid_t uid,
|
|
pid_t pid,
|
|
const std::string& path,
|
|
int device_fd) {
|
|
if (DEBUG_APPFUSE) {
|
|
LOG(DEBUG) << "Run app fuse command " << command << " for the path " << path
|
|
<< " in namespace " << uid;
|
|
}
|
|
|
|
unique_fd dir(open("/proc", O_RDONLY | O_DIRECTORY | O_CLOEXEC));
|
|
if (dir.get() == -1) {
|
|
PLOG(ERROR) << "Failed to open /proc";
|
|
return -errno;
|
|
}
|
|
|
|
// Obtains process file descriptor.
|
|
const std::string pid_str = android::base::StringPrintf("%d", pid);
|
|
const unique_fd pid_fd(
|
|
openat(dir.get(), pid_str.c_str(), O_RDONLY | O_DIRECTORY | O_CLOEXEC));
|
|
if (pid_fd.get() == -1) {
|
|
PLOG(ERROR) << "Failed to open /proc/" << pid;
|
|
return -errno;
|
|
}
|
|
|
|
// Check UID of process.
|
|
{
|
|
struct stat sb;
|
|
const int result = fstat(pid_fd.get(), &sb);
|
|
if (result == -1) {
|
|
PLOG(ERROR) << "Failed to stat /proc/" << pid;
|
|
return -errno;
|
|
}
|
|
if (sb.st_uid != AID_SYSTEM) {
|
|
LOG(ERROR) << "Only system can mount appfuse. UID expected=" << AID_SYSTEM
|
|
<< ", actual=" << sb.st_uid;
|
|
return -EPERM;
|
|
}
|
|
}
|
|
|
|
// Matches so far, but refuse to touch if in root namespace
|
|
{
|
|
std::string rootName;
|
|
std::string pidName;
|
|
if (!android::vold::Readlinkat(dir.get(), "1/ns/mnt", &rootName)
|
|
|| !android::vold::Readlinkat(pid_fd.get(), "ns/mnt", &pidName)) {
|
|
PLOG(ERROR) << "Failed to read namespaces";
|
|
return -EPERM;
|
|
}
|
|
if (rootName == pidName) {
|
|
LOG(ERROR) << "Don't mount appfuse in root namespace";
|
|
return -EPERM;
|
|
}
|
|
}
|
|
|
|
// We purposefully leave the namespace open across the fork
|
|
unique_fd ns_fd(openat(pid_fd.get(), "ns/mnt", O_RDONLY)); // not O_CLOEXEC
|
|
if (ns_fd.get() < 0) {
|
|
PLOG(ERROR) << "Failed to open namespace for /proc/" << pid << "/ns/mnt";
|
|
return -errno;
|
|
}
|
|
|
|
int child = fork();
|
|
if (child == 0) {
|
|
if (setns(ns_fd.get(), CLONE_NEWNS) != 0) {
|
|
PLOG(ERROR) << "Failed to setns";
|
|
_exit(-errno);
|
|
}
|
|
|
|
if (command == "mount") {
|
|
_exit(mountInNamespace(uid, device_fd, path));
|
|
} else if (command == "unmount") {
|
|
// If it's just after all FD opened on mount point are closed, umount2 can fail with
|
|
// EBUSY. To avoid the case, specify MNT_DETACH.
|
|
if (umount2(path.c_str(), UMOUNT_NOFOLLOW | MNT_DETACH) != 0 &&
|
|
errno != EINVAL && errno != ENOENT) {
|
|
PLOG(ERROR) << "Failed to unmount directory.";
|
|
_exit(-errno);
|
|
}
|
|
if (rmdir(path.c_str()) != 0) {
|
|
PLOG(ERROR) << "Failed to remove the mount directory.";
|
|
_exit(-errno);
|
|
}
|
|
_exit(android::OK);
|
|
} else {
|
|
LOG(ERROR) << "Unknown appfuse command " << command;
|
|
_exit(-EPERM);
|
|
}
|
|
}
|
|
|
|
if (child == -1) {
|
|
PLOG(ERROR) << "Failed to folk child process";
|
|
return -errno;
|
|
}
|
|
|
|
android::status_t status;
|
|
TEMP_FAILURE_RETRY(waitpid(child, &status, 0));
|
|
|
|
return status;
|
|
}
|
|
|
|
int VolumeManager::createObb(const std::string& sourcePath, const std::string& sourceKey,
|
|
int32_t ownerGid, std::string* outVolId) {
|
|
int id = mNextObbId++;
|
|
|
|
auto vol = std::shared_ptr<android::vold::VolumeBase>(
|
|
new android::vold::ObbVolume(id, sourcePath, sourceKey, ownerGid));
|
|
vol->create();
|
|
|
|
mObbVolumes.push_back(vol);
|
|
*outVolId = vol->getId();
|
|
return android::OK;
|
|
}
|
|
|
|
int VolumeManager::destroyObb(const std::string& volId) {
|
|
auto i = mObbVolumes.begin();
|
|
while (i != mObbVolumes.end()) {
|
|
if ((*i)->getId() == volId) {
|
|
(*i)->destroy();
|
|
i = mObbVolumes.erase(i);
|
|
} else {
|
|
++i;
|
|
}
|
|
}
|
|
return android::OK;
|
|
}
|
|
|
|
int VolumeManager::mountAppFuse(uid_t uid, pid_t pid, int mountId,
|
|
android::base::unique_fd* device_fd) {
|
|
std::string name = std::to_string(mountId);
|
|
|
|
// Check mount point name.
|
|
std::string path;
|
|
if (getMountPath(uid, name, &path) != android::OK) {
|
|
LOG(ERROR) << "Invalid mount point name";
|
|
return -1;
|
|
}
|
|
|
|
// Create directories.
|
|
const android::status_t result = android::vold::PrepareDir(path, 0700, 0, 0);
|
|
if (result != android::OK) {
|
|
PLOG(ERROR) << "Failed to prepare directory " << path;
|
|
return -1;
|
|
}
|
|
|
|
// Open device FD.
|
|
device_fd->reset(open("/dev/fuse", O_RDWR)); // not O_CLOEXEC
|
|
if (device_fd->get() == -1) {
|
|
PLOG(ERROR) << "Failed to open /dev/fuse";
|
|
return -1;
|
|
}
|
|
|
|
// Mount.
|
|
return runCommandInNamespace("mount", uid, pid, path, device_fd->get());
|
|
}
|
|
|
|
int VolumeManager::unmountAppFuse(uid_t uid, pid_t pid, int mountId) {
|
|
std::string name = std::to_string(mountId);
|
|
|
|
// Check mount point name.
|
|
std::string path;
|
|
if (getMountPath(uid, name, &path) != android::OK) {
|
|
LOG(ERROR) << "Invalid mount point name";
|
|
return -1;
|
|
}
|
|
|
|
return runCommandInNamespace("unmount", uid, pid, path, -1 /* device_fd */);
|
|
}
|