pepper_flash_drm_host.cc revision 7dbb3d5cf0c15f500944d211057644d6a2f37371 
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 "chrome/browser/renderer_host/pepper/pepper_flash_drm_host.h"
6
7#if defined(OS_WIN)
8#include <Windows.h>
9#endif
10
11#include "base/bind.h"
12#include "base/compiler_specific.h"
13#include "base/logging.h"
14#include "base/memory/ref_counted.h"
15#include "content/public/browser/browser_ppapi_host.h"
16#include "content/public/browser/browser_thread.h"
17#include "content/public/browser/child_process_security_policy.h"
18#include "content/public/browser/render_widget_host.h"
19#include "content/public/browser/render_widget_host_view.h"
20#include "content/public/common/pepper_plugin_info.h"
21#include "ppapi/c/pp_errors.h"
22#include "ppapi/host/dispatch_host_message.h"
23#include "ppapi/host/host_message_context.h"
24#include "ppapi/host/ppapi_host.h"
25#include "ppapi/proxy/ppapi_messages.h"
26
27#if defined(USE_AURA)
28#include "ui/aura/root_window.h"
29#endif
30
31using content::BrowserPpapiHost;
32
33namespace chrome {
34
35namespace {
36const base::FilePath::CharType kVoucherFilename[] =
37    FILE_PATH_LITERAL("plugin.vch");
38}
39
40#if defined (OS_WIN)
41// Helper class to get the UI thread which monitor is showing the
42// window associated with the instance's render view. Since we get
43// called by the IO thread and we cannot block, the first answer is
44// of GetMonitor() may be NULL, but eventually it will contain the
45// right monitor.
46class MonitorFinder : public base::RefCountedThreadSafe<MonitorFinder> {
47 public:
48  MonitorFinder(int process_id, int render_id)
49      : process_id_(process_id),
50        render_id_(render_id),
51        monitor_(NULL),
52        request_sent_(0) {
53    GetMonitor();
54  }
55
56  int64_t GetMonitor() {
57    // We use |request_sent_| as an atomic boolean so that we
58    // never have more than one task posted at a given time. We
59    // do this because we don't know how often our client is going
60    // to call and we can't cache the |monitor_| value.
61    if (InterlockedCompareExchange(&request_sent_, 1, 0) == 0) {
62      content::BrowserThread::PostTask(
63          content::BrowserThread::UI, FROM_HERE,
64          base::Bind(&MonitorFinder::FetchMonitorFromWidget, this));
65    }
66    return reinterpret_cast<int64_t>(monitor_);
67  }
68
69 private:
70  friend class base::RefCountedThreadSafe<MonitorFinder>;
71  ~MonitorFinder() { }
72
73  void FetchMonitorFromWidget() {
74    InterlockedExchange(&request_sent_, 0);
75    content::RenderWidgetHost* rwh =
76        content::RenderWidgetHost::FromID(process_id_, render_id_);
77    if (!rwh)
78      return;
79    content::RenderWidgetHostView* view = rwh->GetView();
80    if (!view)
81      return;
82    gfx::NativeView native_view = view->GetNativeView();
83#if defined(USE_AURA)
84    aura::RootWindow* root = native_view->GetRootWindow();
85    if (!root)
86      return;
87    HWND window = root->GetAcceleratedWidget();
88#else
89    HWND window = native_view;
90#endif
91    HMONITOR monitor = ::MonitorFromWindow(window, MONITOR_DEFAULTTONULL);
92    InterlockedExchangePointer(reinterpret_cast<void* volatile *>(&monitor_),
93                               monitor);
94  }
95
96  const int process_id_;
97  const int render_id_;
98  volatile HMONITOR monitor_;
99  volatile long request_sent_;
100};
101#else
102// TODO(cpu): Support Mac and Linux someday.
103class MonitorFinder : public base::RefCountedThreadSafe<MonitorFinder> {
104 public:
105  MonitorFinder(int, int) { }
106  int64_t GetMonitor() { return 0; }
107
108 private:
109  friend class base::RefCountedThreadSafe<MonitorFinder>;
110  ~MonitorFinder() { }
111};
112#endif
113
114PepperFlashDRMHost::PepperFlashDRMHost(BrowserPpapiHost* host,
115                                       PP_Instance instance,
116                                       PP_Resource resource)
117    : ppapi::host::ResourceHost(host->GetPpapiHost(), instance, resource),
118      weak_factory_(this){
119  // Grant permissions to read the flash voucher file.
120  int render_process_id;
121  int render_view_id;
122  bool success =
123      host->GetRenderViewIDsForInstance(
124          instance, &render_process_id, &render_view_id);
125  base::FilePath plugin_dir = host->GetPluginPath().DirName();
126  DCHECK(!plugin_dir.empty() && success);
127  base::FilePath voucher_file = plugin_dir.Append(
128      base::FilePath(kVoucherFilename));
129  content::ChildProcessSecurityPolicy::GetInstance()->GrantReadFile(
130      render_process_id, voucher_file);
131
132  fetcher_ = new DeviceIDFetcher(render_process_id);
133  monitor_finder_ = new MonitorFinder(render_process_id, render_view_id);
134}
135
136PepperFlashDRMHost::~PepperFlashDRMHost() {
137}
138
139int32_t PepperFlashDRMHost::OnResourceMessageReceived(
140    const IPC::Message& msg,
141    ppapi::host::HostMessageContext* context) {
142  IPC_BEGIN_MESSAGE_MAP(PepperFlashDRMHost, msg)
143    PPAPI_DISPATCH_HOST_RESOURCE_CALL_0(PpapiHostMsg_FlashDRM_GetDeviceID,
144                                        OnHostMsgGetDeviceID)
145    PPAPI_DISPATCH_HOST_RESOURCE_CALL_0(PpapiHostMsg_FlashDRM_GetHmonitor,
146                                        OnHostMsgGetHmonitor)
147  IPC_END_MESSAGE_MAP()
148  return PP_ERROR_FAILED;
149}
150
151int32_t PepperFlashDRMHost::OnHostMsgGetDeviceID(
152    ppapi::host::HostMessageContext* context) {
153  if (!fetcher_->Start(base::Bind(&PepperFlashDRMHost::GotDeviceID,
154                                  weak_factory_.GetWeakPtr(),
155                                  context->MakeReplyMessageContext()))) {
156    return PP_ERROR_INPROGRESS;
157  }
158  return PP_OK_COMPLETIONPENDING;
159}
160
161int32_t PepperFlashDRMHost::OnHostMsgGetHmonitor(
162    ppapi::host::HostMessageContext* context) {
163  int64_t monitor_id = monitor_finder_->GetMonitor();
164  if (monitor_id) {
165    context->reply_msg = PpapiPluginMsg_FlashDRM_GetHmonitorReply(monitor_id);
166    return PP_OK;
167  } else {
168    return PP_ERROR_FAILED;
169  }
170}
171
172void PepperFlashDRMHost::GotDeviceID(
173    ppapi::host::ReplyMessageContext reply_context,
174    const std::string& id) {
175  reply_context.params.set_result(
176      id.empty() ? PP_ERROR_FAILED : PP_OK);
177  host()->SendReply(reply_context,
178                    PpapiPluginMsg_FlashDRM_GetDeviceIDReply(id));
179}
180
181}  // namespace chrome
182