15d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)// Copyright 2014 The Chromium Authors. All rights reserved. 25d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)// Use of this source code is governed by a BSD-style license that can be 35d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)// found in the LICENSE file. 45d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) 523730a6e56a168d1879203e4b3819bb36e3d8f1fTorne (Richard Coles)#include "mojo/embedder/platform_channel_pair.h" 65d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) 75d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)#include <fcntl.h> 85d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)#include <sys/socket.h> 95d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)#include <sys/types.h> 105d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)#include <unistd.h> 115d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) 125d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)#include "base/command_line.h" 135d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)#include "base/logging.h" 145d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)#include "base/posix/global_descriptors.h" 155d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)#include "base/strings/string_number_conversions.h" 16effb81e5f8246d0db0270817048dc992db66e9fbBen Murdoch#include "build/build_config.h" 1723730a6e56a168d1879203e4b3819bb36e3d8f1fTorne (Richard Coles)#include "mojo/embedder/platform_handle.h" 185d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) 195d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)namespace mojo { 205d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)namespace embedder { 215d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) 225d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)namespace { 235d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) 245d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)bool IsTargetDescriptorUsed( 255d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) const base::FileHandleMappingVector& file_handle_mapping, 265d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) int target_fd) { 275d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) for (size_t i = 0; i < file_handle_mapping.size(); i++) { 285d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) if (file_handle_mapping[i].second == target_fd) 295d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) return true; 305d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) } 315d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) return false; 325d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)} 335d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) 345d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)} // namespace 355d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) 365d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)PlatformChannelPair::PlatformChannelPair() { 375d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) // Create the Unix domain socket and set the ends to nonblocking. 385d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) int fds[2]; 395d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) // TODO(vtl): Maybe fail gracefully if |socketpair()| fails. 405d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) PCHECK(socketpair(AF_UNIX, SOCK_STREAM, 0, fds) == 0); 415d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) PCHECK(fcntl(fds[0], F_SETFL, O_NONBLOCK) == 0); 425d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) PCHECK(fcntl(fds[1], F_SETFL, O_NONBLOCK) == 0); 435d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) 44effb81e5f8246d0db0270817048dc992db66e9fbBen Murdoch#if defined(OS_MACOSX) 45effb81e5f8246d0db0270817048dc992db66e9fbBen Murdoch // This turns off |SIGPIPE| when writing to a closed socket (causing it to 46effb81e5f8246d0db0270817048dc992db66e9fbBen Murdoch // fail with |EPIPE| instead). On Linux, we have to use |send...()| with 47effb81e5f8246d0db0270817048dc992db66e9fbBen Murdoch // |MSG_NOSIGNAL| -- which is not supported on Mac -- instead. 48effb81e5f8246d0db0270817048dc992db66e9fbBen Murdoch int no_sigpipe = 1; 495f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) PCHECK( 505f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) setsockopt( 515f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) fds[0], SOL_SOCKET, SO_NOSIGPIPE, &no_sigpipe, sizeof(no_sigpipe)) == 525f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 0); 535f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) PCHECK( 545f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) setsockopt( 555f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) fds[1], SOL_SOCKET, SO_NOSIGPIPE, &no_sigpipe, sizeof(no_sigpipe)) == 565f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 0); 57effb81e5f8246d0db0270817048dc992db66e9fbBen Murdoch#endif // defined(OS_MACOSX) 58effb81e5f8246d0db0270817048dc992db66e9fbBen Murdoch 595d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) server_handle_.reset(PlatformHandle(fds[0])); 605d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) DCHECK(server_handle_.is_valid()); 615d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) client_handle_.reset(PlatformHandle(fds[1])); 625d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) DCHECK(client_handle_.is_valid()); 635d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)} 645d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) 655d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)// static 665d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)ScopedPlatformHandle PlatformChannelPair::PassClientHandleFromParentProcess( 67cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles) const base::CommandLine& command_line) { 685d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) std::string client_fd_string = 695d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) command_line.GetSwitchValueASCII(kMojoPlatformChannelHandleSwitch); 705d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) int client_fd = -1; 715d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) if (client_fd_string.empty() || 725d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) !base::StringToInt(client_fd_string, &client_fd) || 735d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) client_fd < base::GlobalDescriptors::kBaseDescriptor) { 745d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) LOG(ERROR) << "Missing or invalid --" << kMojoPlatformChannelHandleSwitch; 755d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) return ScopedPlatformHandle(); 765d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) } 775d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) 785d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) return ScopedPlatformHandle(PlatformHandle(client_fd)); 795d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)} 805d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) 815d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)void PlatformChannelPair::PrepareToPassClientHandleToChildProcess( 82cedac228d2dd51db4b79ea1e72c7f249408ee061Torne (Richard Coles) base::CommandLine* command_line, 835d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) base::FileHandleMappingVector* handle_passing_info) const { 845d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) DCHECK(command_line); 855d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) DCHECK(handle_passing_info); 865d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) // This is an arbitrary sanity check. (Note that this guarantees that the loop 875d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) // below will terminate sanely.) 885d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) CHECK_LT(handle_passing_info->size(), 1000u); 895d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) 905d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) DCHECK(client_handle_.is_valid()); 915d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) 925d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) // Find a suitable FD to map our client handle to in the child process. 935d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) // This has quadratic time complexity in the size of |*handle_passing_info|, 945d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) // but |*handle_passing_info| should be very small (usually/often empty). 955d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) int target_fd = base::GlobalDescriptors::kBaseDescriptor; 965d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) while (IsTargetDescriptorUsed(*handle_passing_info, target_fd)) 975d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) target_fd++; 985d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) 995f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) handle_passing_info->push_back( 1005f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) std::pair<int, int>(client_handle_.get().fd, target_fd)); 1015d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) // Log a warning if the command line already has the switch, but "clobber" it 1025d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) // anyway, since it's reasonably likely that all the switches were just copied 1035d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) // from the parent. 1045d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) LOG_IF(WARNING, command_line->HasSwitch(kMojoPlatformChannelHandleSwitch)) 1055d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) << "Child command line already has switch --" 1065d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) << kMojoPlatformChannelHandleSwitch << "=" 1075d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) << command_line->GetSwitchValueASCII(kMojoPlatformChannelHandleSwitch); 1085d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) // (Any existing switch won't actually be removed from the command line, but 1095d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) // the last one appended takes precedence.) 1105d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) command_line->AppendSwitchASCII(kMojoPlatformChannelHandleSwitch, 1115d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) base::IntToString(target_fd)); 1125d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)} 1135d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles) 1145d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)} // namespace embedder 1155d1f7b1de12d16ceb2c938c56701a3e8bfa558f7Torne (Richard Coles)} // namespace mojo 116