Extract AppFuse as a util
Bug: 110379912
Test: testOpenProxyFileDescriptor
Change-Id: I0429a498d7b54682efe9b05815f3470e8745609e
diff --git a/Android.bp b/Android.bp
index 44e2317..b192b42 100644
--- a/Android.bp
+++ b/Android.bp
@@ -95,6 +95,7 @@
],
srcs: [
+ "AppFuseUtil.cpp",
"Benchmark.cpp",
"CheckEncryption.cpp",
"Checkpoint.cpp",
diff --git a/AppFuseUtil.cpp b/AppFuseUtil.cpp
new file mode 100644
index 0000000..ba82ba5
--- /dev/null
+++ b/AppFuseUtil.cpp
@@ -0,0 +1,164 @@
+/*
+ * 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 "AppFuseUtil.h"
+
+#include <sys/mount.h>
+#include <utils/Errors.h>
+
+#include <android-base/logging.h>
+#include <android-base/stringprintf.h>
+
+#include "Utils.h"
+
+using android::base::StringPrintf;
+
+namespace android {
+namespace vold {
+
+namespace {
+
+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 = StringPrintf("/mnt/appfuse/%d_%s", uid, name.c_str());
+ return android::OK;
+}
+
+static android::status_t Mount(int device_fd, const std::string& path) {
+ // Remove existing mount.
+ android::vold::ForceUnmount(path);
+
+ const auto opts = StringPrintf(
+ "fd=%i,"
+ "rootmode=40000,"
+ "default_permissions,"
+ "allow_other,"
+ "user_id=0,group_id=0,"
+ "context=\"u:object_r:app_fuse_file:s0\","
+ "fscontext=u:object_r:app_fusefs:s0",
+ device_fd);
+
+ 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 RunCommand(const std::string& command, uid_t uid, const std::string& path,
+ int device_fd) {
+ if (DEBUG_APPFUSE) {
+ LOG(DEBUG) << "Run app fuse command " << command << " for the path " << path << " and uid "
+ << uid;
+ }
+
+ if (command == "mount") {
+ return Mount(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.";
+ return -errno;
+ }
+ if (rmdir(path.c_str()) != 0) {
+ PLOG(ERROR) << "Failed to remove the mount directory.";
+ return -errno;
+ }
+ return android::OK;
+ } else {
+ LOG(ERROR) << "Unknown appfuse command " << command;
+ return -EPERM;
+ }
+
+ return android::OK;
+}
+
+} // namespace
+
+int MountAppFuse(uid_t uid, 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 RunCommand("mount", uid, path, device_fd->get());
+}
+
+int UnmountAppFuse(uid_t uid, 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 RunCommand("unmount", uid, path, -1 /* device_fd */);
+}
+
+int OpenAppFuseFile(uid_t uid, int mountId, int fileId, int flags) {
+ std::string name = std::to_string(mountId);
+
+ // Check mount point name.
+ std::string mountPoint;
+ if (GetMountPath(uid, name, &mountPoint) != android::OK) {
+ LOG(ERROR) << "Invalid mount point name";
+ return -1;
+ }
+
+ std::string path = StringPrintf("%s/%d", mountPoint.c_str(), fileId);
+ return TEMP_FAILURE_RETRY(open(path.c_str(), flags));
+}
+
+} // namespace vold
+} // namespace android
diff --git a/AppFuseUtil.h b/AppFuseUtil.h
new file mode 100644
index 0000000..463c6d0
--- /dev/null
+++ b/AppFuseUtil.h
@@ -0,0 +1,36 @@
+/*
+ * 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.
+ */
+
+#ifndef ANDROID_VOLD_APP_FUSE_UTIL_H_
+#define ANDROID_VOLD_APP_FUSE_UTIL_H_
+
+#include <android-base/unique_fd.h>
+
+#define DEBUG_APPFUSE 0
+
+namespace android {
+namespace vold {
+
+int MountAppFuse(uid_t uid, int mountId, android::base::unique_fd* device_fd);
+
+int UnmountAppFuse(uid_t uid, int mountId);
+
+int OpenAppFuseFile(uid_t uid, int mountId, int fileId, int flags);
+
+} // namespace vold
+} // namespace android
+
+#endif // ANDROID_VOLD_APP_FUSE_UTIL_H_
diff --git a/VolumeManager.cpp b/VolumeManager.cpp
index 21136cf..e08319b 100644
--- a/VolumeManager.cpp
+++ b/VolumeManager.cpp
@@ -50,6 +50,7 @@
#include <fscrypt/fscrypt.h>
+#include "AppFuseUtil.h"
#include "Devmapper.h"
#include "FsCrypt.h"
#include "Loop.h"
@@ -631,78 +632,6 @@
}
}
-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 = StringPrintf("/mnt/appfuse/%d_%s", uid, name.c_str());
- return android::OK;
-}
-
-static android::status_t mount(int device_fd, const std::string& path) {
- // Remove existing mount.
- android::vold::ForceUnmount(path);
-
- const auto opts = StringPrintf(
- "fd=%i,"
- "rootmode=40000,"
- "default_permissions,"
- "allow_other,"
- "user_id=0,group_id=0,"
- "context=\"u:object_r:app_fuse_file:s0\","
- "fscontext=u:object_r:app_fusefs:s0",
- device_fd);
-
- 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 runCommand(const std::string& command, uid_t uid, const std::string& path,
- int device_fd) {
- if (DEBUG_APPFUSE) {
- LOG(DEBUG) << "Run app fuse command " << command << " for the path " << path << " and uid "
- << uid;
- }
-
- if (command == "mount") {
- return mount(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.";
- return -errno;
- }
- if (rmdir(path.c_str()) != 0) {
- PLOG(ERROR) << "Failed to remove the mount directory.";
- return -errno;
- }
- return android::OK;
- } else {
- LOG(ERROR) << "Unknown appfuse command " << command;
- return -EPERM;
- }
-
- return android::OK;
-}
-
int VolumeManager::createObb(const std::string& sourcePath, const std::string& sourceKey,
int32_t ownerGid, std::string* outVolId) {
int id = mNextObbId++;
@@ -756,56 +685,13 @@
}
int VolumeManager::mountAppFuse(uid_t uid, int mountId, 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 runCommand("mount", uid, path, device_fd->get());
+ return android::vold::MountAppFuse(uid, mountId, device_fd);
}
int VolumeManager::unmountAppFuse(uid_t uid, 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 runCommand("unmount", uid, path, -1 /* device_fd */);
+ return android::vold::UnmountAppFuse(uid, mountId);
}
int VolumeManager::openAppFuseFile(uid_t uid, int mountId, int fileId, int flags) {
- std::string name = std::to_string(mountId);
-
- // Check mount point name.
- std::string mountPoint;
- if (getMountPath(uid, name, &mountPoint) != android::OK) {
- LOG(ERROR) << "Invalid mount point name";
- return -1;
- }
-
- std::string path = StringPrintf("%s/%d", mountPoint.c_str(), fileId);
- return TEMP_FAILURE_RETRY(open(path.c_str(), flags));
+ return android::vold::OpenAppFuseFile(uid, mountId, fileId, flags);
}
diff --git a/VolumeManager.h b/VolumeManager.h
index a2d6c5b..9227819 100644
--- a/VolumeManager.h
+++ b/VolumeManager.h
@@ -38,8 +38,6 @@
#include "model/Disk.h"
#include "model/VolumeBase.h"
-#define DEBUG_APPFUSE 0
-
class VolumeManager {
private:
static VolumeManager* sInstance;