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/*
* 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 "Fat.h"
#include "PublicVolume.h"
#include "Utils.h"
#include "VolumeManager.h"
#include "ResponseCode.h"
#include <base/stringprintf.h>
#include <base/logging.h>
#include <cutils/fs.h>
#include <private/android_filesystem_config.h>
#include <fcntl.h>
#include <stdlib.h>
#include <sys/mount.h>
#include <sys/stat.h>
#include <sys/types.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);
notifyEvent(ResponseCode::VolumeFsTypeChanged, mFsType);
notifyEvent(ResponseCode::VolumeFsUuidChanged, mFsUuid);
notifyEvent(ResponseCode::VolumeFsLabelChanged, 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() {
// TODO: expand to support mounting other filesystems
readMetadata();
if (Fat::check(mDevPath.c_str())) {
LOG(ERROR) << getId() << " failed filesystem check";
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());
mFusePath = StringPrintf("/storage/%s", stableName.c_str());
setPath(mFusePath);
if (fs_prepare_dir(mRawPath.c_str(), 0700, AID_ROOT, AID_ROOT)) {
PLOG(ERROR) << getId() << " failed to create mount point " << mRawPath;
return -errno;
}
if (fs_prepare_dir(mFusePath.c_str(), 0700, AID_ROOT, AID_ROOT)) {
PLOG(ERROR) << getId() << " failed to create mount point " << mFusePath;
return -errno;
}
if (Fat::doMount(mDevPath.c_str(), mRawPath.c_str(), false, false, false,
AID_MEDIA_RW, AID_MEDIA_RW, 0007, true)) {
PLOG(ERROR) << getId() << " failed to mount " << mDevPath;
return -EIO;
}
if (getMountFlags() & MountFlags::kPrimary) {
initAsecStage();
}
// TODO: teach FUSE daemon to protect itself with user-specific GID
if (!(mFusePid = fork())) {
if (!(getMountFlags() & MountFlags::kVisible)) {
// TODO: mount so that only system apps can access
if (execl(kFusePath, kFusePath,
"-u", "1023", // AID_MEDIA_RW
"-g", "1023", // AID_MEDIA_RW
mRawPath.c_str(),
mFusePath.c_str(),
NULL)) {
PLOG(ERROR) << "Failed to exec";
}
} else if (getMountFlags() & MountFlags::kPrimary) {
if (execl(kFusePath, kFusePath,
"-u", "1023", // AID_MEDIA_RW
"-g", "1023", // AID_MEDIA_RW
"-d",
mRawPath.c_str(),
mFusePath.c_str(),
NULL)) {
PLOG(ERROR) << "Failed to exec";
}
} else {
if (execl(kFusePath, kFusePath,
"-u", "1023", // AID_MEDIA_RW
"-g", "1023", // AID_MEDIA_RW
"-w", "1023", // AID_MEDIA_RW
"-d",
mRawPath.c_str(),
mFusePath.c_str(),
NULL)) {
PLOG(ERROR) << "Failed to exec";
}
}
PLOG(DEBUG) << "FUSE exiting";
_exit(1);
}
if (mFusePid == -1) {
PLOG(ERROR) << getId() << " failed to fork";
return -errno;
}
return OK;
}
status_t PublicVolume::doUnmount() {
if (mFusePid > 0) {
kill(mFusePid, SIGTERM);
TEMP_FAILURE_RETRY(waitpid(mFusePid, nullptr, 0));
mFusePid = 0;
}
ForceUnmount(kAsecPath);
ForceUnmount(mFusePath);
ForceUnmount(mRawPath);
if (TEMP_FAILURE_RETRY(rmdir(mRawPath.c_str()))) {
PLOG(ERROR) << getId() << " failed to rmdir mount point " << mRawPath;
}
if (TEMP_FAILURE_RETRY(rmdir(mFusePath.c_str()))) {
PLOG(ERROR) << getId() << " failed to rmdir mount point " << mFusePath;
}
mFusePath.clear();
mRawPath.clear();
return OK;
}
status_t PublicVolume::doFormat() {
if (Fat::format(mDevPath.c_str(), 0, true)) {
LOG(ERROR) << getId() << " failed to format";
return -errno;
}
return OK;
}
} // namespace vold
} // namespace android