--- services/device/hid/hid_service_fido.cc.orig	2022-06-17 14:20:10 UTC
+++ services/device/hid/hid_service_fido.cc
@@ -0,0 +1,327 @@
+// Copyright 2020 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 "services/device/hid/hid_service_fido.h"
+
+#include <fcntl.h>
+#include <poll.h>
+#include <stdint.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <unistd.h>
+
+// TODO: remove once the missing guard in fido.h is fixed upstream.
+extern "C" {
+#include <fido.h>
+}
+
+#include <set>
+#include <string>
+#include <vector>
+
+#include "base/bind.h"
+#include "base/files/file.h"
+#include "base/files/file_descriptor_watcher_posix.h"
+#include "base/files/file_enumerator.h"
+#include "base/location.h"
+#include "base/logging.h"
+#include "base/posix/eintr_wrapper.h"
+#include "base/task/single_thread_task_runner.h"
+#include "base/task/thread_pool.h"
+#include "base/stl_util.h"
+#include "base/strings/pattern.h"
+#include "base/strings/string_split.h"
+#include "base/strings/string_util.h"
+#include "base/strings/stringprintf.h"
+#include "base/strings/sys_string_conversions.h"
+#include "base/threading/scoped_blocking_call.h"
+#include "base/threading/thread_task_runner_handle.h"
+#include "components/device_event_log/device_event_log.h"
+#include "services/device/hid/hid_connection_fido.h"
+
+namespace device {
+
+namespace {
+
+struct ConnectParams {
+  ConnectParams(scoped_refptr<HidDeviceInfo> device_info,
+                HidService::ConnectCallback callback)
+      : device_info(std::move(device_info)), callback(std::move(callback)),
+        task_runner(base::ThreadTaskRunnerHandle::Get()),
+        blocking_task_runner(base::ThreadPool::CreateSequencedTaskRunner(
+            HidService::kBlockingTaskTraits)) {}
+  ~ConnectParams() {}
+
+  scoped_refptr<HidDeviceInfo> device_info;
+  HidService::ConnectCallback callback;
+  scoped_refptr<base::SequencedTaskRunner> task_runner;
+  scoped_refptr<base::SequencedTaskRunner> blocking_task_runner;
+  base::ScopedFD fd;
+  bool allow_protected_reports;
+  bool allow_fido_reports;
+};
+
+void CreateConnection(std::unique_ptr<ConnectParams> params) {
+  DCHECK(params->fd.is_valid());
+  std::move(params->callback).Run(base::MakeRefCounted<HidConnectionFido>(
+      std::move(params->device_info), std::move(params->fd),
+      std::move(params->blocking_task_runner), params->allow_protected_reports,
+      params->allow_fido_reports));
+}
+
+void FinishOpen(std::unique_ptr<ConnectParams> params) {
+  scoped_refptr<base::SequencedTaskRunner> task_runner = params->task_runner;
+
+  task_runner->PostTask(FROM_HERE,
+                        base::BindOnce(&CreateConnection, std::move(params)));
+}
+
+bool terrible_ping_kludge(int fd, const std::string &path) {
+  u_char data[256];
+  int i, n;
+  struct pollfd pfd;
+
+  for (i = 0; i < 4; i++) {
+    memset(data, 0, sizeof(data));
+    /* broadcast channel ID */
+    data[1] = 0xff;
+    data[2] = 0xff;
+    data[3] = 0xff;
+    data[4] = 0xff;
+    /* Ping command */
+    data[5] = 0x81;
+    /* One byte ping only, Vasili */
+    data[6] = 0;
+    data[7] = 1;
+    HID_LOG(EVENT) << "send ping " << i << " " << path;
+    if (write(fd, data, 64) == -1) {
+      HID_PLOG(ERROR) << "write " << path;
+      return false;
+    }
+    HID_LOG(EVENT) << "wait reply " << path;
+    memset(&pfd, 0, sizeof(pfd));
+    pfd.fd = fd;
+    pfd.events = POLLIN;
+    if ((n = poll(&pfd, 1, 100)) == -1) {
+      HID_PLOG(EVENT) << "poll " << path;
+      return false;
+    } else if (n == 0) {
+      HID_LOG(EVENT) << "timed out " << path;
+      continue;
+    }
+    if (read(fd, data, 64) == -1) {
+      HID_PLOG(ERROR) << "read " << path;
+      return false;
+    }
+    /*
+     * Ping isn't always supported on the broadcast channel,
+     * so we might get an error, but we don't care - we're
+     * synched now.
+     */
+    HID_LOG(EVENT) << "got reply " << path;
+    return true;
+  }
+  HID_LOG(ERROR) << "no response " << path;
+  return false;
+}
+
+void OpenOnBlockingThread(std::unique_ptr<ConnectParams> params) {
+  base::ScopedBlockingCall scoped_blocking_call(FROM_HERE,
+                                                base::BlockingType::MAY_BLOCK);
+  scoped_refptr<base::SequencedTaskRunner> task_runner = params->task_runner;
+
+  const auto &device_node = params->device_info->device_node();
+  base::FilePath device_path(device_node);
+  int flags =
+      base::File::FLAG_OPEN | base::File::FLAG_READ | base::File::FLAG_WRITE;
+  base::File device_file(device_path, flags);
+  if (!device_file.IsValid()) {
+    HID_LOG(EVENT) << "Failed to open '" << device_node << "': "
+                   << base::File::ErrorToString(device_file.error_details());
+    task_runner->PostTask(FROM_HERE, base::BindOnce(std::move(params->callback), nullptr));
+    return;
+  }
+  if (!terrible_ping_kludge(device_file.GetPlatformFile(), device_node)) {
+    HID_LOG(EVENT) << "Failed to ping " << device_node;
+    task_runner->PostTask(FROM_HERE, base::BindOnce(std::move(params->callback), nullptr));
+    return;
+  }
+  params->fd.reset(device_file.TakePlatformFile());
+  FinishOpen(std::move(params));
+}
+
+// HID report descriptor for U2F interface. Copied from:
+// https://chromium.googlesource.com/chromiumos/platform2/+/c6c7e4e54fce11932fedaa3ea10236bf75d85a2b%5E%21/u2fd/u2fhid.cc
+// Apparently Chromium wants to see these bytes, but OpenBSD fido(4)
+// devices prohibit USB_GET_REPORT_DESC ioctl that could be used to
+// get the bytes from the USB device.
+constexpr uint8_t kU2fReportDesc[] = {
+    0x06, 0xD0, 0xF1, /* Usage Page (FIDO Alliance), FIDO_USAGE_PAGE */
+    0x09, 0x01,       /* Usage (U2F HID Auth. Device) FIDO_USAGE_U2FHID */
+    0xA1, 0x01,       /* Collection (Application), HID_APPLICATION */
+    0x09, 0x20,       /*  Usage (Input Report Data), FIDO_USAGE_DATA_IN */
+    0x15, 0x00,       /*  Logical Minimum (0) */
+    0x26, 0xFF, 0x00, /*  Logical Maximum (255) */
+    0x75, 0x08,       /*  Report Size (8) */
+    0x95, 0x40,       /*  Report Count (64), HID_INPUT_REPORT_BYTES */
+    0x81, 0x02,       /*  Input (Data, Var, Abs), Usage */
+    0x09, 0x21,       /*  Usage (Output Report Data), FIDO_USAGE_DATA_OUT */
+    0x15, 0x00,       /*  Logical Minimum (0) */
+    0x26, 0xFF, 0x00, /*  Logical Maximum (255) */
+    0x75, 0x08,       /*  Report Size (8) */
+    0x95, 0x40,       /*  Report Count (64), HID_OUTPUT_REPORT_BYTES */
+    0x91, 0x02,       /*  Output (Data, Var, Abs), Usage */
+    0xC0              /* End Collection */
+};
+
+} // namespace
+
+class HidServiceFido::BlockingTaskHelper {
+public:
+  BlockingTaskHelper(base::WeakPtr<HidServiceFido> service)
+      : service_(std::move(service)),
+        task_runner_(base::ThreadTaskRunnerHandle::Get()) {
+    DETACH_FROM_SEQUENCE(sequence_checker_);
+  }
+
+  BlockingTaskHelper(const BlockingTaskHelper&) = delete;
+  BlockingTaskHelper& operator=(const BlockingTaskHelper&) = delete;
+
+  ~BlockingTaskHelper() = default;
+
+  void Start() {
+    DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
+    base::ScopedBlockingCall scoped_blocking_call(
+        FROM_HERE, base::BlockingType::MAY_BLOCK);
+
+    fido_dev_info_t *devlist = NULL;
+    fido_dev_t *dev = NULL;
+    size_t devlist_len = 0, i;
+    const char *path;
+    int r;
+    const int MAX_FIDO_DEVICES = 256;
+
+    if ((devlist = fido_dev_info_new(MAX_FIDO_DEVICES)) == NULL) {
+      HID_LOG(ERROR) << "fido_dev_info_new failed";
+      goto out;
+    }
+    if ((r = fido_dev_info_manifest(devlist, MAX_FIDO_DEVICES, &devlist_len)) !=
+        FIDO_OK) {
+      HID_LOG(ERROR) << "fido_dev_info_manifest: " << fido_strerr(r);
+      goto out;
+    }
+
+    HID_LOG(EVENT) << "fido_dev_info_manifest found " << devlist_len
+                   << " device(s)";
+
+    for (i = 0; i < devlist_len; i++) {
+      const fido_dev_info_t *di = fido_dev_info_ptr(devlist, i);
+      if (di == NULL) {
+        HID_LOG(ERROR) << "fido_dev_info_ptr " << i << " failed";
+        continue;
+      }
+      if ((path = fido_dev_info_path(di)) == NULL) {
+        HID_LOG(ERROR) << "fido_dev_info_path " << i << " failed";
+        continue;
+      }
+      HID_LOG(EVENT) << "trying device " << i << ": " << path;
+      if ((dev = fido_dev_new()) == NULL) {
+        HID_LOG(ERROR) << "fido_dev_new failed";
+        continue;
+      }
+      if ((r = fido_dev_open(dev, path)) != FIDO_OK) {
+        HID_LOG(ERROR) << "fido_dev_open failed " << path;
+        fido_dev_free(&dev);
+        continue;
+      }
+      OnDeviceAdded(di);
+      fido_dev_close(dev);
+      fido_dev_free(&dev);
+    }
+
+  out:
+    if (devlist != NULL)
+      fido_dev_info_free(&devlist, MAX_FIDO_DEVICES);
+
+    task_runner_->PostTask(
+        FROM_HERE,
+        base::BindOnce(&HidServiceFido::FirstEnumerationComplete, service_));
+  }
+
+  void OnDeviceAdded(const fido_dev_info_t *di) {
+    auto null_as_empty = [](const char *r) -> std::string {
+      return (r != nullptr) ? r : "";
+    };
+    std::string device_node(null_as_empty(fido_dev_info_path(di)));
+    std::vector<uint8_t> report_descriptor(
+        kU2fReportDesc, kU2fReportDesc + sizeof(kU2fReportDesc));
+    scoped_refptr<HidDeviceInfo> device_info(new HidDeviceInfo(
+        device_node, /*physical_device_id=*/"", fido_dev_info_vendor(di),
+        fido_dev_info_product(di), null_as_empty(fido_dev_info_product_string(di)),
+        null_as_empty(fido_dev_info_manufacturer_string(di)),
+        device::mojom::HidBusType::kHIDBusTypeUSB, report_descriptor,
+        device_node));
+
+    task_runner_->PostTask(FROM_HERE, base::BindOnce(&HidServiceFido::AddDevice,
+                                                 service_, device_info));
+  }
+
+  void OnDeviceRemoved(std::string device_node) {
+    base::ScopedBlockingCall scoped_blocking_call(
+        FROM_HERE, base::BlockingType::MAY_BLOCK);
+    task_runner_->PostTask(FROM_HERE, base::BindOnce(&HidServiceFido::RemoveDevice,
+                                                 service_, device_node));
+  }
+
+private:
+  SEQUENCE_CHECKER(sequence_checker_);
+
+  // This weak pointer is only valid when checked on this task runner.
+  base::WeakPtr<HidServiceFido> service_;
+  scoped_refptr<base::SequencedTaskRunner> task_runner_;
+};
+
+HidServiceFido::HidServiceFido()
+    : task_runner_(base::ThreadTaskRunnerHandle::Get()),
+      blocking_task_runner_(
+          base::ThreadPool::CreateSequencedTaskRunner(kBlockingTaskTraits)),
+      weak_factory_(this), helper_(std::make_unique<BlockingTaskHelper>(
+                               weak_factory_.GetWeakPtr())) {
+  blocking_task_runner_->PostTask(
+      FROM_HERE,
+      base::BindOnce(&BlockingTaskHelper::Start, base::Unretained(helper_.get())));
+}
+
+HidServiceFido::~HidServiceFido() {
+  blocking_task_runner_->DeleteSoon(FROM_HERE, helper_.release());
+}
+
+base::WeakPtr<HidService> HidServiceFido::GetWeakPtr() {
+  return weak_factory_.GetWeakPtr();
+}
+
+void HidServiceFido::Connect(const std::string &device_guid,
+                             bool allow_protected_reports,
+                             bool allow_fido_reports,
+                             ConnectCallback callback) {
+  DCHECK_CALLED_ON_VALID_SEQUENCE(sequence_checker_);
+
+  const auto &map_entry = devices().find(device_guid);
+  if (map_entry == devices().end()) {
+    base::ThreadTaskRunnerHandle::Get()->PostTask(
+        FROM_HERE, base::BindOnce(std::move(callback), nullptr));
+    return;
+  }
+
+  scoped_refptr<HidDeviceInfo> device_info = map_entry->second;
+
+  auto params = std::make_unique<ConnectParams>(device_info, std::move(callback));
+
+  scoped_refptr<base::SequencedTaskRunner> blocking_task_runner =
+      params->blocking_task_runner;
+  blocking_task_runner->PostTask(
+      FROM_HERE, base::BindOnce(&OpenOnBlockingThread, std::move(params)));
+}
+
+} // namespace device