1 // Copyright (c) 2012 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 "content/browser/renderer_host/render_sandbox_host_linux.h" 6 7 #include <sys/socket.h> 8 9 #include "base/memory/singleton.h" 10 #include "base/posix/eintr_wrapper.h" 11 12 namespace content { 13 14 // Runs on the main thread at startup. 15 RenderSandboxHostLinux::RenderSandboxHostLinux() 16 : initialized_(false), renderer_socket_(0), childs_lifeline_fd_(0) { 17 } 18 19 // static 20 RenderSandboxHostLinux* RenderSandboxHostLinux::GetInstance() { 21 return Singleton<RenderSandboxHostLinux>::get(); 22 } 23 24 void RenderSandboxHostLinux::Init() { 25 DCHECK(!initialized_); 26 initialized_ = true; 27 28 int fds[2]; 29 // We use SOCK_SEQPACKET rather than SOCK_DGRAM to prevent the renderer from 30 // sending datagrams to other sockets on the system. The sandbox may prevent 31 // the renderer from calling socket() to create new sockets, but it'll still 32 // inherit some sockets. With AF_UNIX+SOCK_DGRAM, it can call sendmsg to send 33 // a datagram to any (abstract) socket on the same system. With 34 // SOCK_SEQPACKET, this is prevented. 35 CHECK(socketpair(AF_UNIX, SOCK_SEQPACKET, 0, fds) == 0); 36 37 renderer_socket_ = fds[0]; 38 // The SandboxIPC client is not expected to read from |renderer_socket_|. 39 // Instead, it reads from a temporary socket sent with the request. 40 PCHECK(0 == shutdown(renderer_socket_, SHUT_RD)) << "shutdown"; 41 42 const int browser_socket = fds[1]; 43 // The SandboxIPC handler is not expected to write to |browser_socket|. 44 // Instead, it replies on a temporary socket provided by the caller. 45 PCHECK(0 == shutdown(browser_socket, SHUT_WR)) << "shutdown"; 46 47 int pipefds[2]; 48 CHECK(0 == pipe(pipefds)); 49 const int child_lifeline_fd = pipefds[0]; 50 childs_lifeline_fd_ = pipefds[1]; 51 52 ipc_handler_.reset( 53 new SandboxIPCHandler(child_lifeline_fd, browser_socket)); 54 ipc_thread_.reset( 55 new base::DelegateSimpleThread(ipc_handler_.get(), "sandbox_ipc_thread")); 56 ipc_thread_->Start(); 57 } 58 59 bool RenderSandboxHostLinux::ShutdownIPCChannel() { 60 return IGNORE_EINTR(close(childs_lifeline_fd_)) == 0; 61 } 62 63 RenderSandboxHostLinux::~RenderSandboxHostLinux() { 64 if (initialized_) { 65 if (!ShutdownIPCChannel()) 66 LOG(ERROR) << "ShutdownIPCChannel failed"; 67 if (IGNORE_EINTR(close(renderer_socket_)) < 0) 68 PLOG(ERROR) << "close"; 69 70 ipc_thread_->Join(); 71 } 72 } 73 74 } // namespace content 75