apps/app_shim/unix_domain_socket_acceptor.cc

   1 // Copyright 2014 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 "apps/app_shim/unix_domain_socket_acceptor.h"
   6
   7 #include "base/files/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 apps {
  13
  14 UnixDomainSocketAcceptor::UnixDomainSocketAcceptor(const base::FilePath& path,
  15                                                    Delegate* delegate)
  16     : path_(path), delegate_(delegate), listen_fd_(-1) {
  17   DCHECK(delegate_);
  18   CreateSocket();
  19 }
  20
  21 UnixDomainSocketAcceptor::~UnixDomainSocketAcceptor() {
  22   Close();
  23 }
  24
  25 bool UnixDomainSocketAcceptor::CreateSocket() {
  26   DCHECK(listen_fd_ < 0);
  27
  28   // Create the socket.
  29   return IPC::CreateServerUnixDomainSocket(path_, &listen_fd_);
  30 }
  31
  32 bool UnixDomainSocketAcceptor::Listen() {
  33   if (listen_fd_ < 0)
  34     return false;
  35
  36   // Watch the fd for connections, and turn any connections into
  37   // active sockets.
  38   base::MessageLoopForIO::current()->WatchFileDescriptor(
  39       listen_fd_,
  40       true,
  41       base::MessageLoopForIO::WATCH_READ,
  42       &server_listen_connection_watcher_,
  43       this);
  44   return true;
  45 }
  46
  47 // Called by libevent when we can read from the fd without blocking.
  48 void UnixDomainSocketAcceptor::OnFileCanReadWithoutBlocking(int fd) {
  49   DCHECK(fd == listen_fd_);
  50   int new_fd = -1;
  51   if (!IPC::ServerAcceptConnection(listen_fd_, &new_fd)) {
  52     Close();
  53     delegate_->OnListenError();
  54     return;
  55   }
  56   base::ScopedFD scoped_fd(new_fd);
  57
  58   if (!scoped_fd.is_valid()) {
  59     // The accept() failed, but not in such a way that the factory needs to be
  60     // shut down.
  61     return;
  62   }
  63
  64   // Verify that the IPC channel peer is running as the same user.
  65   if (!IPC::IsPeerAuthorized(scoped_fd.get()))
  66     return;
  67
  68   IPC::ChannelHandle handle(std::string(),
  69                             base::FileDescriptor(scoped_fd.release(), true));
  70   delegate_->OnClientConnected(handle);
  71 }
  72
  73 void UnixDomainSocketAcceptor::OnFileCanWriteWithoutBlocking(int fd) {
  74   NOTREACHED() << "Listen fd should never be writable.";
  75 }
  76
  77 void UnixDomainSocketAcceptor::Close() {
  78   if (listen_fd_ < 0)
  79     return;
  80   if (IGNORE_EINTR(close(listen_fd_)) < 0)
  81     PLOG(ERROR) << "close";
  82   listen_fd_ = -1;
  83   if (unlink(path_.value().c_str()) < 0)
  84     PLOG(ERROR) << "unlink";
  85
  86   // Unregister libevent for the listening socket and close it.
  87   server_listen_connection_watcher_.StopWatchingFileDescriptor();
  88 }
  89
  90 }  // namespace apps