chrome/utility/image_writer/image_writer_mac.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 <CoreFoundation/CoreFoundation.h>
   6 #include <IOKit/IOBSD.h>
   7 #include <IOKit/IOKitLib.h>
   8 #include <IOKit/storage/IOBlockStorageDevice.h>
   9 #include <IOKit/storage/IOMedia.h>
  10 #include <IOKit/storage/IOStorageProtocolCharacteristics.h>
  11 #include <sys/socket.h>
  12
  13 #include "base/command_line.h"
  14 #include "base/files/scoped_file.h"
  15 #include "base/mac/scoped_cftyperef.h"
  16 #include "base/mac/scoped_ioobject.h"
  17 #include "base/posix/eintr_wrapper.h"
  18 #include "base/process/kill.h"
  19 #include "base/process/launch.h"
  20 #include "base/strings/stringprintf.h"
  21 #include "base/strings/sys_string_conversions.h"
  22 #include "chrome/common/extensions/image_writer/image_writer_util_mac.h"
  23 #include "chrome/utility/image_writer/disk_unmounter_mac.h"
  24 #include "chrome/utility/image_writer/error_messages.h"
  25 #include "chrome/utility/image_writer/image_writer.h"
  26
  27 namespace image_writer {
  28
  29 static const char kAuthOpenPath[] = "/usr/libexec/authopen";
  30
  31 bool ImageWriter::IsValidDevice() {
  32   base::ScopedCFTypeRef<CFStringRef> cf_bsd_name(
  33       base::SysUTF8ToCFStringRef(device_path_.value()));
  34   CFMutableDictionaryRef matching = IOServiceMatching(kIOMediaClass);
  35   CFDictionaryAddValue(matching, CFSTR(kIOMediaWholeKey), kCFBooleanTrue);
  36   CFDictionaryAddValue(matching, CFSTR(kIOMediaWritableKey), kCFBooleanTrue);
  37   CFDictionaryAddValue(matching, CFSTR(kIOBSDNameKey), cf_bsd_name);
  38
  39   io_service_t disk_obj =
  40       IOServiceGetMatchingService(kIOMasterPortDefault, matching);
  41   base::mac::ScopedIOObject<io_service_t> iterator_ref(disk_obj);
  42
  43   if (disk_obj) {
  44     CFMutableDictionaryRef dict;
  45     if (IORegistryEntryCreateCFProperties(
  46             disk_obj, &dict, kCFAllocatorDefault, 0) != KERN_SUCCESS) {
  47       LOG(ERROR) << "Unable to get properties of disk object.";
  48       return false;
  49     }
  50     base::ScopedCFTypeRef<CFMutableDictionaryRef> dict_ref(dict);
  51
  52     CFBooleanRef cf_removable = base::mac::GetValueFromDictionary<CFBooleanRef>(
  53         dict, CFSTR(kIOMediaRemovableKey));
  54     bool removable = CFBooleanGetValue(cf_removable);
  55
  56     bool is_usb = extensions::IsUsbDevice(disk_obj);
  57
  58     return removable || is_usb;
  59   }
  60
  61   return false;
  62 }
  63
  64 void ImageWriter::UnmountVolumes(const base::Closure& continuation) {
  65   if (unmounter_ == NULL) {
  66     unmounter_.reset(new DiskUnmounterMac());
  67   }
  68
  69   unmounter_->Unmount(
  70       device_path_.value(),
  71       continuation,
  72       base::Bind(
  73           &ImageWriter::Error, base::Unretained(this), error::kUnmountVolumes));
  74 }
  75
  76 bool ImageWriter::OpenDevice() {
  77   base::LaunchOptions options = base::LaunchOptions();
  78   options.wait = false;
  79
  80   // Create a socket pair for communication.
  81   int sockets[2];
  82   int result = socketpair(AF_UNIX, SOCK_STREAM, 0, sockets);
  83   if (result == -1) {
  84     PLOG(ERROR) << "Unable to allocate socket pair.";
  85     return false;
  86   }
  87   base::ScopedFD parent_socket(sockets[0]);
  88   base::ScopedFD child_socket(sockets[1]);
  89
  90   // Map the client socket to the client's STDOUT.
  91   base::FileHandleMappingVector fd_map;
  92   fd_map.push_back(std::pair<int, int>(child_socket.get(), STDOUT_FILENO));
  93   options.fds_to_remap = &fd_map;
  94
  95   // Find the file path to open.
  96   base::FilePath real_device_path;
  97   if (device_path_.IsAbsolute()) {
  98     // This only occurs for tests where the device path is mocked with a
  99     // temporary file.
 100     real_device_path = device_path_;
 101   } else {
 102     // Get the raw device file. Writes need to be in multiples of
 103     // DAMediaBlockSize (usually 512). This is fine since WriteChunk() writes in
 104     // multiples of kMemoryAlignment.
 105     real_device_path =
 106         base::FilePath("/dev").Append("r" + device_path_.BaseName().value());
 107   }
 108
 109   // Build the command line.
 110   std::string rdwr = base::StringPrintf("%d", O_RDWR);
 111
 112   base::CommandLine cmd_line = base::CommandLine(base::FilePath(kAuthOpenPath));
 113   cmd_line.AppendSwitch("-stdoutpipe");
 114   // Using AppendSwitchNative will use an equal-symbol which we don't want.
 115   cmd_line.AppendArg("-o");
 116   cmd_line.AppendArg(rdwr);
 117   cmd_line.AppendArgPath(real_device_path);
 118
 119   // Launch the process.
 120   base::Process process = base::LaunchProcess(cmd_line, options);
 121   if (!process.IsValid()) {
 122     LOG(ERROR) << "Failed to launch authopen process.";
 123     return false;
 124   }
 125
 126   // Receive a file descriptor from authopen which sends a single FD via
 127   // sendmsg and the SCM_RIGHTS extension.
 128   int fd = -1;
 129   const size_t kDataBufferSize = sizeof(struct cmsghdr) + sizeof(int);
 130   char data_buffer[kDataBufferSize];
 131
 132   struct iovec io_vec[1];
 133   io_vec[0].iov_base = data_buffer;
 134   io_vec[0].iov_len = kDataBufferSize;
 135
 136   const socklen_t kCmsgSocketSize =
 137       static_cast<socklen_t>(CMSG_SPACE(sizeof(int)));
 138   char cmsg_socket[kCmsgSocketSize];
 139
 140   struct msghdr message = {0};
 141   message.msg_iov = io_vec;
 142   message.msg_iovlen = 1;
 143   message.msg_control = cmsg_socket;
 144   message.msg_controllen = kCmsgSocketSize;
 145
 146   ssize_t size = HANDLE_EINTR(recvmsg(parent_socket.get(), &message, 0));
 147   if (size > 0) {
 148     struct cmsghdr* cmsg_socket_header = CMSG_FIRSTHDR(&message);
 149
 150     if (cmsg_socket_header && cmsg_socket_header->cmsg_level == SOL_SOCKET &&
 151         cmsg_socket_header->cmsg_type == SCM_RIGHTS) {
 152       fd = *reinterpret_cast<int*>(CMSG_DATA(cmsg_socket_header));
 153     }
 154   }
 155
 156   device_file_ = base::File(fd);
 157
 158   // Wait for the child.
 159   int child_exit_status;
 160   if (!process.WaitForExit(&child_exit_status)) {
 161     LOG(ERROR) << "Unable to wait for child.";
 162     return false;
 163   }
 164
 165   if (child_exit_status) {
 166     LOG(ERROR) << "Child process returned failure.";
 167     return false;
 168   }
 169
 170   return device_file_.IsValid();
 171 }
 172
 173 }  // namespace image_writer