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Diffstat (limited to 'ipc/chromium/src/chrome/common/ipc_channel_posix.h')
| -rw-r--r-- | ipc/chromium/src/chrome/common/ipc_channel_posix.h | 227 |
1 files changed, 227 insertions, 0 deletions
diff --git a/ipc/chromium/src/chrome/common/ipc_channel_posix.h b/ipc/chromium/src/chrome/common/ipc_channel_posix.h new file mode 100644 index 0000000000..43670db01c --- /dev/null +++ b/ipc/chromium/src/chrome/common/ipc_channel_posix.h @@ -0,0 +1,227 @@ +/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* vim: set ts=8 sts=2 et sw=2 tw=80: */ +// Copyright (c) 2008 The Chromium Authors. All rights reserved. +// Use of this source code is governed by a BSD-style license that can be +// found in the LICENSE file. + +#ifndef CHROME_COMMON_IPC_CHANNEL_POSIX_H_ +#define CHROME_COMMON_IPC_CHANNEL_POSIX_H_ + +#include "chrome/common/ipc_channel.h" +#include "chrome/common/ipc_channel_capability.h" + +#include <sys/socket.h> // for CMSG macros + +#include <atomic> +#include <string> +#include <vector> +#include <list> + +#include "base/message_loop.h" +#include "base/task.h" + +#include "mozilla/Maybe.h" +#include "mozilla/Queue.h" +#include "mozilla/UniquePtr.h" +#include "mozilla/UniquePtrExtensions.h" +#include "nsISupports.h" + +namespace IPC { + +// An implementation of ChannelImpl for POSIX systems that works via +// socketpairs. See the .cc file for an overview of the implementation. +class Channel::ChannelImpl : public MessageLoopForIO::Watcher { + public: + NS_INLINE_DECL_THREADSAFE_REFCOUNTING_WITH_DELETE_ON_EVENT_TARGET( + ChannelImpl, IOThread().GetEventTarget()); + + using ChannelId = Channel::ChannelId; + + // Mirror methods of Channel, see ipc_channel.h for description. + ChannelImpl(const ChannelId& channel_id, Mode mode, Listener* listener); + ChannelImpl(ChannelHandle pipe, Mode mode, Listener* listener); + bool Connect() MOZ_EXCLUDES(SendMutex()); + void Close() MOZ_EXCLUDES(SendMutex()); + Listener* set_listener(Listener* listener) { + IOThread().AssertOnCurrentThread(); + chan_cap_.NoteOnIOThread(); + Listener* old = listener_; + listener_ = listener; + return old; + } + // NOTE: `Send` may be called on threads other than the I/O thread. + bool Send(mozilla::UniquePtr<Message> message) MOZ_EXCLUDES(SendMutex()); + void GetClientFileDescriptorMapping(int* src_fd, int* dest_fd) const; + + void CloseClientFileDescriptor(); + + int32_t OtherPid() { + IOThread().AssertOnCurrentThread(); + chan_cap_.NoteOnIOThread(); + return other_pid_; + } + + // See the comment in ipc_channel.h for info on IsClosed() + // NOTE: `IsClosed` may be called on threads other than the I/O thread. + bool IsClosed() MOZ_EXCLUDES(SendMutex()) { + mozilla::MutexAutoLock lock(SendMutex()); + chan_cap_.NoteSendMutex(); + return pipe_ == -1; + } + +#if defined(OS_MACOSX) + void SetOtherMachTask(task_t task) MOZ_EXCLUDES(SendMutex()); + + void StartAcceptingMachPorts(Mode mode) MOZ_EXCLUDES(SendMutex()); +#endif + + private: + ~ChannelImpl() { Close(); } + + void Init(Mode mode, Listener* listener) + MOZ_REQUIRES(SendMutex(), IOThread()); + bool CreatePipe(Mode mode) MOZ_REQUIRES(SendMutex(), IOThread()); + void SetPipe(int fd) MOZ_REQUIRES(SendMutex(), IOThread()); + void SetOtherPid(int other_pid) MOZ_REQUIRES(IOThread()) + MOZ_EXCLUDES(SendMutex()) { + mozilla::MutexAutoLock lock(SendMutex()); + chan_cap_.NoteExclusiveAccess(); + other_pid_ = other_pid; + } + bool PipeBufHasSpaceAfter(size_t already_written) + MOZ_REQUIRES_SHARED(chan_cap_); + bool EnqueueHelloMessage() MOZ_REQUIRES(SendMutex(), IOThread()); + bool ConnectLocked() MOZ_REQUIRES(SendMutex(), IOThread()); + void CloseLocked() MOZ_REQUIRES(SendMutex(), IOThread()); + + bool ProcessIncomingMessages() MOZ_REQUIRES(IOThread()); + bool ProcessOutgoingMessages() MOZ_REQUIRES(SendMutex()); + + // MessageLoopForIO::Watcher implementation. + virtual void OnFileCanReadWithoutBlocking(int fd) override; + virtual void OnFileCanWriteWithoutBlocking(int fd) override; + +#if defined(OS_MACOSX) + void CloseDescriptors(uint32_t pending_fd_id) MOZ_REQUIRES(IOThread()) + MOZ_EXCLUDES(SendMutex()); + + // Called on a Message immediately before it is sent/recieved to transfer + // handles to the remote process, or accept handles from the remote process. + bool AcceptMachPorts(Message& msg) MOZ_REQUIRES(IOThread()); + bool TransferMachPorts(Message& msg) MOZ_REQUIRES_SHARED(chan_cap_); +#endif + + void OutputQueuePush(mozilla::UniquePtr<Message> msg) + MOZ_REQUIRES(SendMutex()); + void OutputQueuePop() MOZ_REQUIRES(SendMutex()); + + const ChannelCapability::Thread& IOThread() const + MOZ_RETURN_CAPABILITY(chan_cap_.IOThread()) { + return chan_cap_.IOThread(); + } + + ChannelCapability::Mutex& SendMutex() + MOZ_RETURN_CAPABILITY(chan_cap_.SendMutex()) { + return chan_cap_.SendMutex(); + } + + // Compound capability of a Mutex and the IO thread. + ChannelCapability chan_cap_; + + Mode mode_ MOZ_GUARDED_BY(IOThread()); + + // After accepting one client connection on our server socket we want to + // stop listening. + MessageLoopForIO::FileDescriptorWatcher read_watcher_ + MOZ_GUARDED_BY(IOThread()); + MessageLoopForIO::FileDescriptorWatcher write_watcher_ + MOZ_GUARDED_BY(IOThread()); + + // Indicates whether we're currently blocked waiting for a write to complete. + bool is_blocked_on_write_ MOZ_GUARDED_BY(SendMutex()) = false; + + // If sending a message blocks then we use this iterator to keep track of + // where in the message we are. It gets reset when the message is finished + // sending. + struct PartialWrite { + Pickle::BufferList::IterImpl iter_; + mozilla::Span<const mozilla::UniqueFileHandle> handles_; + }; + mozilla::Maybe<PartialWrite> partial_write_ MOZ_GUARDED_BY(SendMutex()); + + int pipe_ MOZ_GUARDED_BY(chan_cap_); + // The client end of our socketpair(). + int client_pipe_ MOZ_GUARDED_BY(IOThread()); + // The SO_SNDBUF value of pipe_, or 0 if unknown. + unsigned pipe_buf_len_ MOZ_GUARDED_BY(chan_cap_); + + Listener* listener_ MOZ_GUARDED_BY(IOThread()); + + // Messages to be sent are queued here. + mozilla::Queue<mozilla::UniquePtr<Message>, 64> output_queue_ + MOZ_GUARDED_BY(SendMutex()); + + // We read from the pipe into these buffers. + size_t input_buf_offset_ MOZ_GUARDED_BY(IOThread()); + mozilla::UniquePtr<char[]> input_buf_ MOZ_GUARDED_BY(IOThread()); + mozilla::UniquePtr<char[]> input_cmsg_buf_ MOZ_GUARDED_BY(IOThread()); + + // The control message buffer will hold all of the file descriptors that will + // be read in during a single recvmsg call. Message::WriteFileDescriptor + // always writes one word of data for every file descriptor added to the + // message, and the number of file descriptors per recvmsg will not exceed + // kControlBufferMaxFds. This is based on the true maximum SCM_RIGHTS + // descriptor count, which is just over 250 on both Linux and macOS. + // + // This buffer also holds a control message header of size CMSG_SPACE(0) + // bytes. However, CMSG_SPACE is not a constant on Macs, so we can't use it + // here. Consequently, we pick a number here that is at least CMSG_SPACE(0) on + // all platforms. We assert at runtime, in Channel::ChannelImpl::Init, that + // it's big enough. + static constexpr size_t kControlBufferMaxFds = 200; + static constexpr size_t kControlBufferHeaderSize = 32; + static constexpr size_t kControlBufferSize = + kControlBufferMaxFds * sizeof(int) + kControlBufferHeaderSize; + + // Large incoming messages that span multiple pipe buffers get built-up in the + // buffers of this message. + mozilla::UniquePtr<Message> incoming_message_ MOZ_GUARDED_BY(IOThread()); + std::vector<int> input_overflow_fds_ MOZ_GUARDED_BY(IOThread()); + + // Will be set to `true` until `Connect()` has been called and communication + // is ready. For privileged connections on macOS, this will not be cleared + // until the peer mach port has been provided to allow transferring mach + // ports. + bool waiting_connect_ MOZ_GUARDED_BY(chan_cap_) = true; + + // We keep track of the PID of the other side of this channel so that we can + // record this when generating logs of IPC messages. + int32_t other_pid_ MOZ_GUARDED_BY(chan_cap_) = -1; + +#if defined(OS_MACOSX) + struct PendingDescriptors { + uint32_t id; + nsTArray<mozilla::UniqueFileHandle> handles; + }; + + std::list<PendingDescriptors> pending_fds_ MOZ_GUARDED_BY(SendMutex()); + + // A generation ID for RECEIVED_FD messages. + uint32_t last_pending_fd_id_ MOZ_GUARDED_BY(SendMutex()) = 0; + + // Whether or not to accept mach ports from a remote process, and whether this + // process is the privileged side of a IPC::Channel which can transfer mach + // ports. + bool accept_mach_ports_ MOZ_GUARDED_BY(chan_cap_) = false; + bool privileged_ MOZ_GUARDED_BY(chan_cap_) = false; + + // If available, the task port for the remote process. + mozilla::UniqueMachSendRight other_task_ MOZ_GUARDED_BY(chan_cap_); +#endif + + DISALLOW_COPY_AND_ASSIGN(ChannelImpl); +}; + +} // namespace IPC + +#endif // CHROME_COMMON_IPC_CHANNEL_POSIX_H_ |