| // Copyright (C) 2020 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. |
| |
| #pragma once |
| |
| #include <unistd.h> |
| |
| #include <chrono> |
| #include <cstring> |
| #include <iostream> |
| #include <string> |
| #include <thread> |
| #include <vector> |
| |
| #include <android-base/unique_fd.h> |
| |
| namespace android { |
| namespace snapshot { |
| |
| static constexpr uint32_t PACKET_SIZE = 512; |
| |
| static constexpr char kSnapuserdSocket[] = "snapuserd"; |
| static constexpr char kSnapuserdSocketProxy[] = "snapuserd_proxy"; |
| |
| // Ensure that the second-stage daemon for snapuserd is running. |
| bool EnsureSnapuserdStarted(); |
| |
| class SnapuserdClient { |
| private: |
| android::base::unique_fd sockfd_; |
| |
| bool Sendmsg(const std::string& msg); |
| std::string Receivemsg(); |
| |
| bool ValidateConnection(); |
| |
| public: |
| explicit SnapuserdClient(android::base::unique_fd&& sockfd); |
| |
| static std::unique_ptr<SnapuserdClient> Connect(const std::string& socket_name, |
| std::chrono::milliseconds timeout_ms); |
| |
| bool StopSnapuserd(); |
| |
| // Initializing a snapuserd handler is a three-step process: |
| // |
| // 1. Client invokes InitDmUserCow. This creates the snapuserd handler and validates the |
| // COW. The number of sectors required for the dm-user target is returned. |
| // 2. Client creates the device-mapper device with the dm-user target. |
| // 3. Client calls AttachControlDevice. |
| // |
| // The misc_name must be the "misc_name" given to dm-user in step 2. |
| // |
| uint64_t InitDmUserCow(const std::string& misc_name, const std::string& cow_device, |
| const std::string& backing_device); |
| bool AttachDmUser(const std::string& misc_name); |
| |
| // Wait for snapuserd to disassociate with a dm-user control device. This |
| // must ONLY be called if the control device has already been deleted. |
| bool WaitForDeviceDelete(const std::string& control_device); |
| |
| void CloseConnection() { sockfd_ = {}; } |
| |
| // Detach snapuserd. This shuts down the listener socket, and will cause |
| // snapuserd to gracefully exit once all handler threads have terminated. |
| // This should only be used on first-stage instances of snapuserd. |
| bool DetachSnapuserd(); |
| |
| // Returns true if the snapuserd instance supports bridging a socket to second-stage init. |
| bool SupportsSecondStageSocketHandoff(); |
| }; |
| |
| } // namespace snapshot |
| } // namespace android |