device/hid/hid_service_linux.cc - chromium/src - Git at Google

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 #include "device/hid/hid_service_linux.h"

 #include <fcntl.h>
 #include <stdint.h>

 #include <limits>
 #include <memory>
 #include <string>
 #include <utility>

 #include "base/bind.h"
 #include "base/files/file.h"
 #include "base/files/file_path.h"
 #include "base/files/file_util.h"
 #include "base/location.h"
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
 #include "base/scoped_observer.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_split.h"
 #include "base/threading/thread_restrictions.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "build/build_config.h"
 #include "components/device_event_log/device_event_log.h"
 #include "device/base/device_monitor_linux.h"
 #include "device/hid/hid_connection_linux.h"
 #include "device/hid/hid_device_info_linux.h"
 #include "device/udev_linux/scoped_udev.h"

 #if defined(OS_CHROMEOS)
 #include "base/sys_info.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "chromeos/dbus/permission_broker_client.h"
 #endif  // defined(OS_CHROMEOS)

 namespace device {

 namespace {

 const char kHidrawSubsystem[] = "hidraw";
 const char kHIDID[] = "HID_ID";
 const char kHIDName[] = "HID_NAME";
 const char kHIDUnique[] = "HID_UNIQ";
 const char kSysfsReportDescriptorKey[] = "report_descriptor";

 }  // namespace

 struct HidServiceLinux::ConnectParams {
   ConnectParams(scoped_refptr<HidDeviceInfoLinux> device_info,
                 const ConnectCallback& callback,
                 scoped_refptr<base::SingleThreadTaskRunner> task_runner,
                 scoped_refptr<base::SingleThreadTaskRunner> file_task_runner)
       : device_info(device_info),
         callback(callback),
         task_runner(task_runner),
         file_task_runner(file_task_runner) {}
   ~ConnectParams() {}

   scoped_refptr<HidDeviceInfoLinux> device_info;
   ConnectCallback callback;
   scoped_refptr<base::SingleThreadTaskRunner> task_runner;
   scoped_refptr<base::SingleThreadTaskRunner> file_task_runner;
   base::File device_file;
 };

 class HidServiceLinux::FileThreadHelper : public DeviceMonitorLinux::Observer {
  public:
   FileThreadHelper(base::WeakPtr<HidServiceLinux> service,
                    scoped_refptr<base::SingleThreadTaskRunner> task_runner)
       : observer_(this), service_(service), task_runner_(task_runner) {
     thread_checker_.DetachFromThread();
   }

   ~FileThreadHelper() override {
     DCHECK(thread_checker_.CalledOnValidThread());
   }

   void Start() {
     base::ThreadRestrictions::AssertIOAllowed();
     DCHECK(thread_checker_.CalledOnValidThread());

     DeviceMonitorLinux* monitor = DeviceMonitorLinux::GetInstance();
     observer_.Add(monitor);
     monitor->Enumerate(
         base::Bind(&FileThreadHelper::OnDeviceAdded, base::Unretained(this)));
     task_runner_->PostTask(
         FROM_HERE,
         base::Bind(&HidServiceLinux::FirstEnumerationComplete, service_));
   }

  private:
   // DeviceMonitorLinux::Observer:
   void OnDeviceAdded(udev_device* device) override {
     DCHECK(thread_checker_.CalledOnValidThread());
     const char* device_path = udev_device_get_syspath(device);
     if (!device_path) {
       return;
     }
     HidDeviceId device_id = device_path;

     const char* subsystem = udev_device_get_subsystem(device);
     if (!subsystem || strcmp(subsystem, kHidrawSubsystem) != 0) {
       return;
     }

     const char* str_property = udev_device_get_devnode(device);
     if (!str_property) {
       return;
     }
     std::string device_node = str_property;

     udev_device* parent = udev_device_get_parent(device);
     if (!parent) {
       return;
     }

     const char* hid_id = udev_device_get_property_value(parent, kHIDID);
     if (!hid_id) {
       return;
     }

     std::vector<std::string> parts = base::SplitString(
         hid_id, ":", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL);
     if (parts.size() != 3) {
       return;
     }

     uint32_t int_property = 0;
     if (!HexStringToUInt(base::StringPiece(parts[1]), &int_property) ||
         int_property > std::numeric_limits<uint16_t>::max()) {
       return;
     }
     uint16_t vendor_id = int_property;

     if (!HexStringToUInt(base::StringPiece(parts[2]), &int_property) ||
         int_property > std::numeric_limits<uint16_t>::max()) {
       return;
     }
     uint16_t product_id = int_property;

     std::string serial_number;
     str_property = udev_device_get_property_value(parent, kHIDUnique);
     if (str_property != NULL) {
       serial_number = str_property;
     }

     std::string product_name;
     str_property = udev_device_get_property_value(parent, kHIDName);
     if (str_property != NULL) {
       product_name = str_property;
     }

     const char* parent_sysfs_path = udev_device_get_syspath(parent);
     if (!parent_sysfs_path) {
       return;
     }
     base::FilePath report_descriptor_path =
         base::FilePath(parent_sysfs_path).Append(kSysfsReportDescriptorKey);
     std::string report_descriptor_str;
     if (!base::ReadFileToString(report_descriptor_path,
                                 &report_descriptor_str)) {
       return;
     }

     scoped_refptr<HidDeviceInfo> device_info(new HidDeviceInfoLinux(
         device_id, device_node, vendor_id, product_id, product_name,
         serial_number,
         kHIDBusTypeUSB,  // TODO(reillyg): Detect Bluetooth. crbug.com/443335
         std::vector<uint8_t>(report_descriptor_str.begin(),
                              report_descriptor_str.end())));

     task_runner_->PostTask(FROM_HERE, base::Bind(&HidServiceLinux::AddDevice,
                                                  service_, device_info));
   }

   void OnDeviceRemoved(udev_device* device) override {
     DCHECK(thread_checker_.CalledOnValidThread());
     const char* device_path = udev_device_get_syspath(device);
     if (device_path) {
       task_runner_->PostTask(
           FROM_HERE, base::Bind(&HidServiceLinux::RemoveDevice, service_,
                                 std::string(device_path)));
     }
   }

   base::ThreadChecker thread_checker_;
   ScopedObserver<DeviceMonitorLinux, DeviceMonitorLinux::Observer> observer_;

   // This weak pointer is only valid when checked on this task runner.
   base::WeakPtr<HidServiceLinux> service_;
   scoped_refptr<base::SingleThreadTaskRunner> task_runner_;

   DISALLOW_COPY_AND_ASSIGN(FileThreadHelper);
 };

 HidServiceLinux::HidServiceLinux(
     scoped_refptr<base::SingleThreadTaskRunner> file_task_runner)
     : file_task_runner_(std::move(file_task_runner)), weak_factory_(this) {
   task_runner_ = base::ThreadTaskRunnerHandle::Get();
   helper_ = base::MakeUnique<FileThreadHelper>(weak_factory_.GetWeakPtr(),
                                                task_runner_);
   file_task_runner_->PostTask(
       FROM_HERE,
       base::Bind(&FileThreadHelper::Start, base::Unretained(helper_.get())));
 }

 HidServiceLinux::~HidServiceLinux() {
   DCHECK(!helper_);
 }

 void HidServiceLinux::Shutdown() {
   const bool did_post_task =
       file_task_runner_->DeleteSoon(FROM_HERE, helper_.release());
   DCHECK(did_post_task);
   HidService::Shutdown();
 }

 void HidServiceLinux::Connect(const HidDeviceId& device_id,
                               const ConnectCallback& callback) {
   DCHECK(thread_checker_.CalledOnValidThread());

   const auto& map_entry = devices().find(device_id);
   if (map_entry == devices().end()) {
     task_runner_->PostTask(FROM_HERE, base::Bind(callback, nullptr));
     return;
   }
   scoped_refptr<HidDeviceInfoLinux> device_info =
       static_cast<HidDeviceInfoLinux*>(map_entry->second.get());

   std::unique_ptr<ConnectParams> params(new ConnectParams(
       device_info, callback, task_runner_, file_task_runner_));

 #if defined(OS_CHROMEOS)
   chromeos::PermissionBrokerClient* client =
       chromeos::DBusThreadManager::Get()->GetPermissionBrokerClient();
   DCHECK(client) << "Could not get permission broker client.";
   chromeos::PermissionBrokerClient::ErrorCallback error_callback =
       base::Bind(&HidServiceLinux::OnPathOpenError,
                  params->device_info->device_node(), params->callback);
   client->OpenPath(
       device_info->device_node(),
       base::Bind(&HidServiceLinux::OnPathOpenComplete, base::Passed(&params)),
       error_callback);
 #else
   file_task_runner_->PostTask(FROM_HERE,
                               base::Bind(&HidServiceLinux::OpenOnBlockingThread,
                                          base::Passed(&params)));
 #endif  // defined(OS_CHROMEOS)
 }

 #if defined(OS_CHROMEOS)

 // static
 void HidServiceLinux::OnPathOpenComplete(std::unique_ptr<ConnectParams> params,
                                          base::ScopedFD fd) {
   scoped_refptr<base::SingleThreadTaskRunner> file_task_runner =
       params->file_task_runner;
   params->device_file = base::File(fd.release());
   file_task_runner->PostTask(FROM_HERE, base::Bind(&HidServiceLinux::FinishOpen,
                                                    base::Passed(&params)));
 }

 // static
 void HidServiceLinux::OnPathOpenError(const std::string& device_path,
                                       const ConnectCallback& callback,
                                       const std::string& error_name,
                                       const std::string& error_message) {
   HID_LOG(EVENT) << "Permission broker failed to open '" << device_path
                  << "': " << error_name << ": " << error_message;
   callback.Run(nullptr);
 }

 #else

 // static
 void HidServiceLinux::OpenOnBlockingThread(
     std::unique_ptr<ConnectParams> params) {
   base::ThreadRestrictions::AssertIOAllowed();
   scoped_refptr<base::SingleThreadTaskRunner> task_runner = params->task_runner;

   base::FilePath device_path(params->device_info->device_node());
   base::File& device_file = params->device_file;
   int flags =
       base::File::FLAG_OPEN | base::File::FLAG_READ | base::File::FLAG_WRITE;
   device_file.Initialize(device_path, flags);
   if (!device_file.IsValid()) {
     base::File::Error file_error = device_file.error_details();

     if (file_error == base::File::FILE_ERROR_ACCESS_DENIED) {
       HID_LOG(EVENT)
           << "Access denied opening device read-write, trying read-only.";
       flags = base::File::FLAG_OPEN | base::File::FLAG_READ;
       device_file.Initialize(device_path, flags);
     }
   }
   if (!device_file.IsValid()) {
     HID_LOG(EVENT) << "Failed to open '" << params->device_info->device_node()
                    << "': "
                    << base::File::ErrorToString(device_file.error_details());
     task_runner->PostTask(FROM_HERE, base::Bind(params->callback, nullptr));
     return;
   }

   FinishOpen(std::move(params));
 }

 #endif  // defined(OS_CHROMEOS)

 // static
 void HidServiceLinux::FinishOpen(std::unique_ptr<ConnectParams> params) {
   base::ThreadRestrictions::AssertIOAllowed();
   scoped_refptr<base::SingleThreadTaskRunner> task_runner = params->task_runner;

   if (!base::SetNonBlocking(params->device_file.GetPlatformFile())) {
     HID_PLOG(ERROR) << "Failed to set the non-blocking flag on the device fd";
     task_runner->PostTask(FROM_HERE, base::Bind(params->callback, nullptr));
     return;
   }

   task_runner->PostTask(
       FROM_HERE,
       base::Bind(&HidServiceLinux::CreateConnection, base::Passed(&params)));
 }

 // static
 void HidServiceLinux::CreateConnection(std::unique_ptr<ConnectParams> params) {
   DCHECK(params->device_file.IsValid());
   params->callback.Run(make_scoped_refptr(new HidConnectionLinux(
       params->device_info, std::move(params->device_file),
       params->file_task_runner)));
 }

 }  // namespace device
	// Copyright 2014 The Chromium Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	#include "device/hid/hid_service_linux.h"

	#include <fcntl.h>
	#include <stdint.h>

	#include <limits>
	#include <memory>
	#include <string>
	#include <utility>

	#include "base/bind.h"
	#include "base/files/file.h"
	#include "base/files/file_path.h"
	#include "base/files/file_util.h"
	#include "base/location.h"
	#include "base/macros.h"
	#include "base/memory/ptr_util.h"
	#include "base/scoped_observer.h"
	#include "base/strings/string_number_conversions.h"
	#include "base/strings/string_split.h"
	#include "base/threading/thread_restrictions.h"
	#include "base/threading/thread_task_runner_handle.h"
	#include "build/build_config.h"
	#include "components/device_event_log/device_event_log.h"
	#include "device/base/device_monitor_linux.h"
	#include "device/hid/hid_connection_linux.h"
	#include "device/hid/hid_device_info_linux.h"
	#include "device/udev_linux/scoped_udev.h"

	#if defined(OS_CHROMEOS)
	#include "base/sys_info.h"
	#include "chromeos/dbus/dbus_thread_manager.h"
	#include "chromeos/dbus/permission_broker_client.h"
	#endif // defined(OS_CHROMEOS)

	namespace device {

	namespace {

	const char kHidrawSubsystem[] = "hidraw";
	const char kHIDID[] = "HID_ID";
	const char kHIDName[] = "HID_NAME";
	const char kHIDUnique[] = "HID_UNIQ";
	const char kSysfsReportDescriptorKey[] = "report_descriptor";

	} // namespace

	struct HidServiceLinux::ConnectParams {
	ConnectParams(scoped_refptr<HidDeviceInfoLinux> device_info,
	const ConnectCallback& callback,
	scoped_refptr<base::SingleThreadTaskRunner> task_runner,
	scoped_refptr<base::SingleThreadTaskRunner> file_task_runner)
	: device_info(device_info),
	callback(callback),
	task_runner(task_runner),
	file_task_runner(file_task_runner) {}
	~ConnectParams() {}

	scoped_refptr<HidDeviceInfoLinux> device_info;
	ConnectCallback callback;
	scoped_refptr<base::SingleThreadTaskRunner> task_runner;
	scoped_refptr<base::SingleThreadTaskRunner> file_task_runner;
	base::File device_file;
	};

	class HidServiceLinux::FileThreadHelper : public DeviceMonitorLinux::Observer {
	public:
	FileThreadHelper(base::WeakPtr<HidServiceLinux> service,
	scoped_refptr<base::SingleThreadTaskRunner> task_runner)
	: observer_(this), service_(service), task_runner_(task_runner) {
	thread_checker_.DetachFromThread();
	}

	~FileThreadHelper() override {
	DCHECK(thread_checker_.CalledOnValidThread());
	}

	void Start() {
	base::ThreadRestrictions::AssertIOAllowed();
	DCHECK(thread_checker_.CalledOnValidThread());

	DeviceMonitorLinux* monitor = DeviceMonitorLinux::GetInstance();
	observer_.Add(monitor);
	monitor->Enumerate(
	base::Bind(&FileThreadHelper::OnDeviceAdded, base::Unretained(this)));
	task_runner_->PostTask(
	FROM_HERE,
	base::Bind(&HidServiceLinux::FirstEnumerationComplete, service_));
	}

	private:
	// DeviceMonitorLinux::Observer:
	void OnDeviceAdded(udev_device* device) override {
	DCHECK(thread_checker_.CalledOnValidThread());
	const char* device_path = udev_device_get_syspath(device);
	if (!device_path) {
	return;
	}
	HidDeviceId device_id = device_path;

	const char* subsystem = udev_device_get_subsystem(device);
	if (!subsystem \|\| strcmp(subsystem, kHidrawSubsystem) != 0) {
	return;
	}

	const char* str_property = udev_device_get_devnode(device);
	if (!str_property) {
	return;
	}
	std::string device_node = str_property;

	udev_device* parent = udev_device_get_parent(device);
	if (!parent) {
	return;
	}

	const char* hid_id = udev_device_get_property_value(parent, kHIDID);
	if (!hid_id) {
	return;
	}

	std::vector<std::string> parts = base::SplitString(
	hid_id, ":", base::TRIM_WHITESPACE, base::SPLIT_WANT_ALL);
	if (parts.size() != 3) {
	return;
	}

	uint32_t int_property = 0;
	if (!HexStringToUInt(base::StringPiece(parts[1]), &int_property) \|\|
	int_property > std::numeric_limits<uint16_t>::max()) {
	return;
	}
	uint16_t vendor_id = int_property;

	if (!HexStringToUInt(base::StringPiece(parts[2]), &int_property) \|\|
	int_property > std::numeric_limits<uint16_t>::max()) {
	return;
	}
	uint16_t product_id = int_property;

	std::string serial_number;
	str_property = udev_device_get_property_value(parent, kHIDUnique);
	if (str_property != NULL) {
	serial_number = str_property;
	}

	std::string product_name;
	str_property = udev_device_get_property_value(parent, kHIDName);
	if (str_property != NULL) {
	product_name = str_property;
	}

	const char* parent_sysfs_path = udev_device_get_syspath(parent);
	if (!parent_sysfs_path) {
	return;
	}
	base::FilePath report_descriptor_path =
	base::FilePath(parent_sysfs_path).Append(kSysfsReportDescriptorKey);
	std::string report_descriptor_str;
	if (!base::ReadFileToString(report_descriptor_path,
	&report_descriptor_str)) {
	return;
	}

	scoped_refptr<HidDeviceInfo> device_info(new HidDeviceInfoLinux(
	device_id, device_node, vendor_id, product_id, product_name,
	serial_number,
	kHIDBusTypeUSB, // TODO(reillyg): Detect Bluetooth. crbug.com/443335
	std::vector<uint8_t>(report_descriptor_str.begin(),
	report_descriptor_str.end())));

	task_runner_->PostTask(FROM_HERE, base::Bind(&HidServiceLinux::AddDevice,
	service_, device_info));
	}

	void OnDeviceRemoved(udev_device* device) override {
	DCHECK(thread_checker_.CalledOnValidThread());
	const char* device_path = udev_device_get_syspath(device);
	if (device_path) {
	task_runner_->PostTask(
	FROM_HERE, base::Bind(&HidServiceLinux::RemoveDevice, service_,
	std::string(device_path)));
	}
	}

	base::ThreadChecker thread_checker_;
	ScopedObserver<DeviceMonitorLinux, DeviceMonitorLinux::Observer> observer_;

	// This weak pointer is only valid when checked on this task runner.
	base::WeakPtr<HidServiceLinux> service_;
	scoped_refptr<base::SingleThreadTaskRunner> task_runner_;

	DISALLOW_COPY_AND_ASSIGN(FileThreadHelper);
	};

	HidServiceLinux::HidServiceLinux(
	scoped_refptr<base::SingleThreadTaskRunner> file_task_runner)
	: file_task_runner_(std::move(file_task_runner)), weak_factory_(this) {
	task_runner_ = base::ThreadTaskRunnerHandle::Get();
	helper_ = base::MakeUnique<FileThreadHelper>(weak_factory_.GetWeakPtr(),
	task_runner_);
	file_task_runner_->PostTask(
	FROM_HERE,
	base::Bind(&FileThreadHelper::Start, base::Unretained(helper_.get())));
	}

	HidServiceLinux::~HidServiceLinux() {
	DCHECK(!helper_);
	}

	void HidServiceLinux::Shutdown() {
	const bool did_post_task =
	file_task_runner_->DeleteSoon(FROM_HERE, helper_.release());
	DCHECK(did_post_task);
	HidService::Shutdown();
	}

	void HidServiceLinux::Connect(const HidDeviceId& device_id,
	const ConnectCallback& callback) {
	DCHECK(thread_checker_.CalledOnValidThread());

	const auto& map_entry = devices().find(device_id);
	if (map_entry == devices().end()) {
	task_runner_->PostTask(FROM_HERE, base::Bind(callback, nullptr));
	return;
	}
	scoped_refptr<HidDeviceInfoLinux> device_info =
	static_cast<HidDeviceInfoLinux*>(map_entry->second.get());

	std::unique_ptr<ConnectParams> params(new ConnectParams(
	device_info, callback, task_runner_, file_task_runner_));

	#if defined(OS_CHROMEOS)
	chromeos::PermissionBrokerClient* client =
	chromeos::DBusThreadManager::Get()->GetPermissionBrokerClient();
	DCHECK(client) << "Could not get permission broker client.";
	chromeos::PermissionBrokerClient::ErrorCallback error_callback =
	base::Bind(&HidServiceLinux::OnPathOpenError,
	params->device_info->device_node(), params->callback);
	client->OpenPath(
	device_info->device_node(),
	base::Bind(&HidServiceLinux::OnPathOpenComplete, base::Passed(&params)),
	error_callback);
	#else
	file_task_runner_->PostTask(FROM_HERE,
	base::Bind(&HidServiceLinux::OpenOnBlockingThread,
	base::Passed(&params)));
	#endif // defined(OS_CHROMEOS)
	}

	#if defined(OS_CHROMEOS)

	// static
	void HidServiceLinux::OnPathOpenComplete(std::unique_ptr<ConnectParams> params,
	base::ScopedFD fd) {
	scoped_refptr<base::SingleThreadTaskRunner> file_task_runner =
	params->file_task_runner;
	params->device_file = base::File(fd.release());
	file_task_runner->PostTask(FROM_HERE, base::Bind(&HidServiceLinux::FinishOpen,
	base::Passed(&params)));
	}

	// static
	void HidServiceLinux::OnPathOpenError(const std::string& device_path,
	const ConnectCallback& callback,
	const std::string& error_name,
	const std::string& error_message) {
	HID_LOG(EVENT) << "Permission broker failed to open '" << device_path
	<< "': " << error_name << ": " << error_message;
	callback.Run(nullptr);
	}

	#else

	// static
	void HidServiceLinux::OpenOnBlockingThread(
	std::unique_ptr<ConnectParams> params) {
	base::ThreadRestrictions::AssertIOAllowed();
	scoped_refptr<base::SingleThreadTaskRunner> task_runner = params->task_runner;

	base::FilePath device_path(params->device_info->device_node());
	base::File& device_file = params->device_file;
	int flags =
	base::File::FLAG_OPEN \| base::File::FLAG_READ \| base::File::FLAG_WRITE;
	device_file.Initialize(device_path, flags);
	if (!device_file.IsValid()) {
	base::File::Error file_error = device_file.error_details();

	if (file_error == base::File::FILE_ERROR_ACCESS_DENIED) {
	HID_LOG(EVENT)
	<< "Access denied opening device read-write, trying read-only.";
	flags = base::File::FLAG_OPEN \| base::File::FLAG_READ;
	device_file.Initialize(device_path, flags);
	}
	}
	if (!device_file.IsValid()) {
	HID_LOG(EVENT) << "Failed to open '" << params->device_info->device_node()
	<< "': "
	<< base::File::ErrorToString(device_file.error_details());
	task_runner->PostTask(FROM_HERE, base::Bind(params->callback, nullptr));
	return;
	}

	FinishOpen(std::move(params));
	}

	#endif // defined(OS_CHROMEOS)

	// static
	void HidServiceLinux::FinishOpen(std::unique_ptr<ConnectParams> params) {
	base::ThreadRestrictions::AssertIOAllowed();
	scoped_refptr<base::SingleThreadTaskRunner> task_runner = params->task_runner;

	if (!base::SetNonBlocking(params->device_file.GetPlatformFile())) {
	HID_PLOG(ERROR) << "Failed to set the non-blocking flag on the device fd";
	task_runner->PostTask(FROM_HERE, base::Bind(params->callback, nullptr));
	return;
	}

	task_runner->PostTask(
	FROM_HERE,
	base::Bind(&HidServiceLinux::CreateConnection, base::Passed(&params)));
	}

	// static
	void HidServiceLinux::CreateConnection(std::unique_ptr<ConnectParams> params) {
	DCHECK(params->device_file.IsValid());
	params->callback.Run(make_scoped_refptr(new HidConnectionLinux(
	params->device_info, std::move(params->device_file),
	params->file_task_runner)));
	}

	} // namespace device