1 // Copyright 2013 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "ipc/ipc_channel_factory.h"
6
7 #include "base/file_util.h"
8 #include "base/files/scoped_file.h"
9 #include "base/logging.h"
10 #include "ipc/unix_domain_socket_util.h"
11
12 namespace IPC {
13
ChannelFactory(const base::FilePath & path,Delegate * delegate)14 ChannelFactory::ChannelFactory(const base::FilePath& path, Delegate* delegate)
15 : path_(path), delegate_(delegate), listen_fd_(-1) {
16 DCHECK(delegate_);
17 CreateSocket();
18 }
19
~ChannelFactory()20 ChannelFactory::~ChannelFactory() {
21 Close();
22 }
23
CreateSocket()24 bool ChannelFactory::CreateSocket() {
25 DCHECK(listen_fd_ < 0);
26
27 // Create the socket.
28 return CreateServerUnixDomainSocket(path_, &listen_fd_);
29 }
30
Listen()31 bool ChannelFactory::Listen() {
32 if (listen_fd_ < 0)
33 return false;
34
35 // Watch the fd for connections, and turn any connections into
36 // active sockets.
37 base::MessageLoopForIO::current()->WatchFileDescriptor(
38 listen_fd_,
39 true,
40 base::MessageLoopForIO::WATCH_READ,
41 &server_listen_connection_watcher_,
42 this);
43 return true;
44 }
45
46 // Called by libevent when we can read from the fd without blocking.
OnFileCanReadWithoutBlocking(int fd)47 void ChannelFactory::OnFileCanReadWithoutBlocking(int fd) {
48 DCHECK(fd == listen_fd_);
49 int new_fd = -1;
50 if (!ServerAcceptConnection(listen_fd_, &new_fd)) {
51 Close();
52 delegate_->OnListenError();
53 return;
54 }
55 base::ScopedFD scoped_fd(new_fd);
56
57 if (!scoped_fd.is_valid()) {
58 // The accept() failed, but not in such a way that the factory needs to be
59 // shut down.
60 return;
61 }
62
63 // Verify that the IPC channel peer is running as the same user.
64 if (!IsPeerAuthorized(scoped_fd.get()))
65 return;
66
67 ChannelHandle handle(std::string(),
68 base::FileDescriptor(scoped_fd.release(), true));
69 delegate_->OnClientConnected(handle);
70 }
71
OnFileCanWriteWithoutBlocking(int fd)72 void ChannelFactory::OnFileCanWriteWithoutBlocking(int fd) {
73 NOTREACHED() << "Listen fd should never be writable.";
74 }
75
Close()76 void ChannelFactory::Close() {
77 if (listen_fd_ < 0)
78 return;
79 if (IGNORE_EINTR(close(listen_fd_)) < 0)
80 PLOG(ERROR) << "close";
81 listen_fd_ = -1;
82 if (unlink(path_.value().c_str()) < 0)
83 PLOG(ERROR) << "unlink";
84
85 // Unregister libevent for the listening socket and close it.
86 server_listen_connection_watcher_.StopWatchingFileDescriptor();
87 }
88
89 } // namespace IPC
90