/*
* Copyright (C) 2015 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 "PublicVolume.h"
#include "Utils.h"
#include "VolumeManager.h"
#include "fs/Exfat.h"
#include "fs/Vfat.h"
#include <android-base/stringprintf.h>
#include <android-base/logging.h>
#include <cutils/fs.h>
#include <private/android_filesystem_config.h>
#include <utils/Timers.h>
#include <fcntl.h>
#include <stdlib.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/sysmacros.h>
#include <sys/wait.h>
using android::base::StringPrintf;
namespace android {
namespace vold {
static const char* kFusePath = "/system/bin/sdcard";
static const char* kAsecPath = "/mnt/secure/asec";
PublicVolume::PublicVolume(dev_t device) :
VolumeBase(Type::kPublic), mDevice(device), mFusePid(0) {
setId(StringPrintf("public:%u,%u", major(device), minor(device)));
mDevPath = StringPrintf("/dev/block/vold/%s", getId().c_str());
}
PublicVolume::~PublicVolume() {
}
status_t PublicVolume::readMetadata() {
status_t res = ReadMetadataUntrusted(mDevPath, &mFsType, &mFsUuid, &mFsLabel);
auto listener = getListener();
if (listener) listener->onVolumeMetadataChanged(getId(), mFsType, mFsUuid, mFsLabel);
return res;
}
status_t PublicVolume::initAsecStage() {
std::string legacyPath(mRawPath + "/android_secure");
std::string securePath(mRawPath + "/.android_secure");
// Recover legacy secure path
if (!access(legacyPath.c_str(), R_OK | X_OK)
&& access(securePath.c_str(), R_OK | X_OK)) {
if (rename(legacyPath.c_str(), securePath.c_str())) {
PLOG(WARNING) << getId() << " failed to rename legacy ASEC dir";
}
}
if (TEMP_FAILURE_RETRY(mkdir(securePath.c_str(), 0700))) {
if (errno != EEXIST) {
PLOG(WARNING) << getId() << " creating ASEC stage failed";
return -errno;
}
}
BindMount(securePath, kAsecPath);
return OK;
}
status_t PublicVolume::doCreate() {
return CreateDeviceNode(mDevPath, mDevice);
}
status_t PublicVolume::doDestroy() {
return DestroyDeviceNode(mDevPath);
}
status_t PublicVolume::doMount() {
readMetadata();
if (mFsType == "vfat" && vfat::IsSupported()) {
if (vfat::Check(mDevPath)) {
LOG(ERROR) << getId() << " failed filesystem check";
return -EIO;
}
} else if (mFsType == "exfat" && exfat::IsSupported()) {
if (exfat::Check(mDevPath)) {
LOG(ERROR) << getId() << " failed filesystem check";
return -EIO;
}
} else {
LOG(ERROR) << getId() << " unsupported filesystem " << mFsType;
return -EIO;
}
// Use UUID as stable name, if available
std::string stableName = getId();
if (!mFsUuid.empty()) {
stableName = mFsUuid;
}
mRawPath = StringPrintf("/mnt/media_rw/%s", stableName.c_str());
mFuseDefault = StringPrintf("/mnt/runtime/default/%s", stableName.c_str());
mFuseRead = StringPrintf("/mnt/runtime/read/%s", stableName.c_str());
mFuseWrite = StringPrintf("/mnt/runtime/write/%s", stableName.c_str());
setInternalPath(mRawPath);
if (getMountFlags() & MountFlags::kVisible) {
setPath(StringPrintf("/storage/%s", stableName.c_str()));
} else {
setPath(mRawPath);
}
if (fs_prepare_dir(mRawPath.c_str(), 0700, AID_ROOT, AID_ROOT)) {
PLOG(ERROR) << getId() << " failed to create mount points";
return -errno;
}
if (mFsType == "vfat") {
if (vfat::Mount(mDevPath, mRawPath, false, false, false, AID_MEDIA_RW, AID_MEDIA_RW, 0007,
true)) {
PLOG(ERROR) << getId() << " failed to mount " << mDevPath;
return -EIO;
}
} else if (mFsType == "exfat") {
if (exfat::Mount(mDevPath, mRawPath, AID_MEDIA_RW, AID_MEDIA_RW, 0007)) {
PLOG(ERROR) << getId() << " failed to mount " << mDevPath;
return -EIO;
}
}
if (getMountFlags() & MountFlags::kPrimary) {
initAsecStage();
}
if (!(getMountFlags() & MountFlags::kVisible)) {
// Not visible to apps, so no need to spin up FUSE
return OK;
}
if (fs_prepare_dir(mFuseDefault.c_str(), 0700, AID_ROOT, AID_ROOT) ||
fs_prepare_dir(mFuseRead.c_str(), 0700, AID_ROOT, AID_ROOT) ||
fs_prepare_dir(mFuseWrite.c_str(), 0700, AID_ROOT, AID_ROOT)) {
PLOG(ERROR) << getId() << " failed to create FUSE mount points";
return -errno;
}
dev_t before = GetDevice(mFuseWrite);
if (!(mFusePid = fork())) {
if (getMountFlags() & MountFlags::kPrimary) {
if (execl(kFusePath, kFusePath,
"-u", "1023", // AID_MEDIA_RW
"-g", "1023", // AID_MEDIA_RW
"-U", std::to_string(getMountUserId()).c_str(),
"-w",
mRawPath.c_str(),
stableName.c_str(),
NULL)) {
PLOG(ERROR) << "Failed to exec";
}
} else {
if (execl(kFusePath, kFusePath,
"-u", "1023", // AID_MEDIA_RW
"-g", "1023", // AID_MEDIA_RW
"-U", std::to_string(getMountUserId()).c_str(),
mRawPath.c_str(),
stableName.c_str(),
NULL)) {
PLOG(ERROR) << "Failed to exec";
}
}
LOG(ERROR) << "FUSE exiting";
_exit(1);
}
if (mFusePid == -1) {
PLOG(ERROR) << getId() << " failed to fork";
return -errno;
}
nsecs_t start = systemTime(SYSTEM_TIME_BOOTTIME);
while (before == GetDevice(mFuseWrite)) {
LOG(VERBOSE) << "Waiting for FUSE to spin up...";
usleep(50000); // 50ms
nsecs_t now = systemTime(SYSTEM_TIME_BOOTTIME);
if (nanoseconds_to_milliseconds(now - start) > 5000) {
LOG(WARNING) << "Timed out while waiting for FUSE to spin up";
return -ETIMEDOUT;
}
}
/* sdcardfs will have exited already. FUSE will still be running */
if (TEMP_FAILURE_RETRY(waitpid(mFusePid, nullptr, WNOHANG)) == mFusePid)
mFusePid = 0;
return OK;
}
status_t PublicVolume::doUnmount() {
// Unmount the storage before we kill the FUSE process. If we kill
// the FUSE process first, most file system operations will return
// ENOTCONN until the unmount completes. This is an exotic and unusual
// error code and might cause broken behaviour in applications.
KillProcessesUsingPath(getPath());
ForceUnmount(kAsecPath);
ForceUnmount(mFuseDefault);
ForceUnmount(mFuseRead);
ForceUnmount(mFuseWrite);
ForceUnmount(mRawPath);
if (mFusePid > 0) {
kill(mFusePid, SIGTERM);
TEMP_FAILURE_RETRY(waitpid(mFusePid, nullptr, 0));
mFusePid = 0;
}
rmdir(mFuseDefault.c_str());
rmdir(mFuseRead.c_str());
rmdir(mFuseWrite.c_str());
rmdir(mRawPath.c_str());
mFuseDefault.clear();
mFuseRead.clear();
mFuseWrite.clear();
mRawPath.clear();
return OK;
}
status_t PublicVolume::doFormat(const std::string& fsType) {
if ((fsType == "vfat" || fsType == "auto") && vfat::IsSupported()) {
if (WipeBlockDevice(mDevPath) != OK) {
LOG(WARNING) << getId() << " failed to wipe";
}
if (vfat::Format(mDevPath, 0)) {
LOG(ERROR) << getId() << " failed to format";
return -errno;
}
} else if ((fsType == "exfat" || fsType == "auto") && exfat::IsSupported()) {
if (WipeBlockDevice(mDevPath) != OK) {
LOG(WARNING) << getId() << " failed to wipe";
}
if (exfat::Format(mDevPath)) {
LOG(ERROR) << getId() << " failed to format";
return -errno;
}
} else {
LOG(ERROR) << "Unsupported filesystem " << fsType;
return -EINVAL;
}
return OK;
}
} // namespace vold
} // namespace android