Add CdmService to keep track of CDMs

chrome/common/chrome_content_client.cc

Index: chrome/common/chrome_content_client.cc
diff --git a/chrome/common/chrome_content_client.cc b/chrome/common/chrome_content_client.cc
index 4a2456f278f66a9a9ef94f3723c46f458e1cb281..7e28bb0d5d67dfd4689f374b56959fca4c941d80 100644
--- a/chrome/common/chrome_content_client.cc
+++ b/chrome/common/chrome_content_client.cc
@@ -31,6 +31,7 @@
 #include "components/data_reduction_proxy/content/common/data_reduction_proxy_messages.h"
 #include "components/dom_distiller/core/url_constants.h"
 #include "components/version_info/version_info.h"
+#include "content/public/common/cdm_info.h"
 #include "content/public/common/content_constants.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/common/url_constants.h"
@@ -98,6 +99,35 @@ content::PepperPluginInfo::PPP_InitializeModuleFunc g_nacl_initialize_module;
 content::PepperPluginInfo::PPP_ShutdownModuleFunc g_nacl_shutdown_module;
 #endif
 
+#if defined(WIDEVINE_CDM_AVAILABLE) && !defined(WIDEVINE_CDM_IS_COMPONENT)
+static bool IsWidevineAvailable(

[ddorwin, 2016/03/18 19:24:18]

GetWidevine<Something> would be more accurate.

[jrummell, 2016/03/23 21:38:09]

However, the function returns bool to indicate if WV available or not. Not sure
of a different name that isn't really long.

+    base::FilePath* cdm_adapter_path,
+    std::vector<base::string16>* codecs_supported,

[ddorwin, 2016/03/18 19:24:18]

Should we really be working in string16 here? I think that is specific to the
plugin code, so we should handle it there.

[jrummell, 2016/03/23 21:38:09]

Done.

+    std::vector<base::string16>* supported_init_data_types) {

[ddorwin, 2016/03/18 19:24:17]

supported_init_data_types is never used. Even without the TODO below, these
could be populated. There might be a separate TODO to pass them from the browser
process rather than deriving them in the renderer.

Regardless, it's weird to have an unused parameter now.

[jrummell, 2016/03/23 21:38:09]

Removed.

+  static bool skip_widevine_cdm_file_check = false;
+  if (PathService::Get(chrome::FILE_WIDEVINE_CDM_ADAPTER, cdm_adapter_path)) {

[ddorwin, 2016/03/18 20:38:53]

This code will compile on all platforms except Windows and Mac. You need the
equivalent of ENABLE_PEPPER_CDMS so that this only runs on desktop.

Related to my comment below, you'll also need to decide whether this entire
function is desktop-specific or whether you'll have the desktop path extract
information from the results.

[ddorwin, 2016/03/18 20:48:56]

Note that the previous location of this was protected by if
defined(ENABLE_PEPPER_CDMS). This needs to be protected by the equivalent of "is
desktop cdm". But this function - or similar - needs to run and be accurate on
all platforms. IOW, Android should support AddContentDecryptionModules(), right?

[xhwang, 2016/03/18 20:57:58]

Note sure if I understand the question completely :)

Android doesn't need this CL. The reason we have these logic in the browser is
(1) To populate key system info* (2) CDM is component updated (3) CDM is is a
separate binary so we need preloading. None of these apply to Android.

On Android, the CDM is the MediaDrmBridge.

* Note that CdmMessageFilterAndroid::OnQueryKeySystemSupport() doesn't use
anything here.

[ddorwin, 2016/03/18 22:22:11]

I thought the CDM Registry and related IPCs were going to unify all these paths.
That was my intent, at least.

[xhwang, 2016/03/18 23:16:02]

Agreed that we should unify the two IPC paths. I imagine it'll be a mojo call
where the mojo service is hosted by CdmService directly.

+    if (skip_widevine_cdm_file_check || base::PathExists(*cdm_adapter_path)) {
+      skip_widevine_cdm_file_check = true;
+
+      // Add the supported codecs as if they came from the component manifest.
+      // This list must match the CDM that is being bundled with Chrome.
+      codecs_supported->push_back(base::ASCIIToUTF16(kCdmSupportedCodecVp8));
+      codecs_supported->push_back(base::ASCIIToUTF16(kCdmSupportedCodecVp9));
+#if defined(USE_PROPRIETARY_CODECS)
+      codecs_supported->push_back(base::ASCIIToUTF16(kCdmSupportedCodecAvc1));
+#endif  // defined(USE_PROPRIETARY_CODECS)
+
+      // TODO(crbug.com/469202). Add support for initDataTypes in the component
+      // manifest, and then duplicate the settings here.
+      return true;
+    }
+  }
+
+  return false;
+}
+#endif  // defined(WIDEVINE_CDM_AVAILABLE) &&
+        // !defined(WIDEVINE_CDM_IS_COMPONENT)
+
 // Appends the known built-in plugins to the given vector. Some built-in
 // plugins are "internal" which means they are compiled into the Chrome binary,
 // and some are extra shared libraries distributed with the browser (these are
@@ -155,43 +185,31 @@ void ComputeBuiltInPlugins(std::vector<content::PepperPluginInfo>* plugins) {
 
 #if defined(WIDEVINE_CDM_AVAILABLE) && defined(ENABLE_PEPPER_CDMS) && \
     !defined(WIDEVINE_CDM_IS_COMPONENT)

[xhwang, 2016/03/18 19:35:38]

Why remove skip_widevine_cdm_file_check?

[jrummell, 2016/03/23 21:38:09]

It has simply moved to the IsWidevineAvailable() method.

-  static bool skip_widevine_cdm_file_check = false;
-  if (PathService::Get(chrome::FILE_WIDEVINE_CDM_ADAPTER, &path)) {
-    if (skip_widevine_cdm_file_check || base::PathExists(path)) {
-      content::PepperPluginInfo widevine_cdm;
-      widevine_cdm.is_out_of_process = true;
-      widevine_cdm.path = path;
-      widevine_cdm.name = kWidevineCdmDisplayName;
-      widevine_cdm.description = kWidevineCdmDescription +
-                                 std::string(" (version: ") +
-                                 WIDEVINE_CDM_VERSION_STRING + ")";
-      widevine_cdm.version = WIDEVINE_CDM_VERSION_STRING;
-      content::WebPluginMimeType widevine_cdm_mime_type(
-          kWidevineCdmPluginMimeType,
-          kWidevineCdmPluginExtension,
-          kWidevineCdmPluginMimeTypeDescription);
-
-      // Add the supported codecs as if they came from the component manifest.
-      // This list must match the CDM that is being bundled with Chrome.
-      std::vector<std::string> codecs;
-      codecs.push_back(kCdmSupportedCodecVp8);
-      codecs.push_back(kCdmSupportedCodecVp9);
-#if defined(USE_PROPRIETARY_CODECS)
-      codecs.push_back(kCdmSupportedCodecAvc1);
-#endif  // defined(USE_PROPRIETARY_CODECS)
-      std::string codec_string = base::JoinString(
-          codecs, std::string(1, kCdmSupportedCodecsValueDelimiter));
-      widevine_cdm_mime_type.additional_param_names.push_back(
-          base::ASCIIToUTF16(kCdmSupportedCodecsParamName));
-      widevine_cdm_mime_type.additional_param_values.push_back(
-          base::ASCIIToUTF16(codec_string));
-
-      widevine_cdm.mime_types.push_back(widevine_cdm_mime_type);
-      widevine_cdm.permissions = kWidevineCdmPluginPermissions;
-      plugins->push_back(widevine_cdm);
-
-      skip_widevine_cdm_file_check = true;
-    }
+  std::vector<base::string16> codecs_supported;
+  std::vector<base::string16> supported_init_data_types;
+  if (IsWidevineAvailable(&path, &codecs_supported,
+                          &supported_init_data_types)) {
+    content::PepperPluginInfo widevine_cdm;
+    widevine_cdm.is_out_of_process = true;
+    widevine_cdm.path = path;
+    widevine_cdm.name = kWidevineCdmDisplayName;
+    widevine_cdm.description = kWidevineCdmDescription +
+                               std::string(" (version: ") +
+                               WIDEVINE_CDM_VERSION_STRING + ")";
+    widevine_cdm.version = WIDEVINE_CDM_VERSION_STRING;
+    content::WebPluginMimeType widevine_cdm_mime_type(
+        kWidevineCdmPluginMimeType, kWidevineCdmPluginExtension,
+        kWidevineCdmPluginMimeTypeDescription);
+
+    widevine_cdm_mime_type.additional_param_names.push_back(
+        base::ASCIIToUTF16(kCdmSupportedCodecsParamName));
+    widevine_cdm_mime_type.additional_param_values.push_back(base::JoinString(
+        codecs_supported,
+        base::ASCIIToUTF16(std::string(1, kCdmSupportedCodecsValueDelimiter))));
+
+    widevine_cdm.mime_types.push_back(widevine_cdm_mime_type);
+    widevine_cdm.permissions = kWidevineCdmPluginPermissions;
+    plugins->push_back(widevine_cdm);
   }
 #endif  // defined(WIDEVINE_CDM_AVAILABLE) && defined(ENABLE_PEPPER_CDMS) &&
         // !defined(WIDEVINE_CDM_IS_COMPONENT)
@@ -520,6 +538,26 @@ void ChromeContentClient::AddPepperPlugins(
 #endif  // defined(ENABLE_PLUGINS)
 }
 
+void ChromeContentClient::AddContentDecryptionModules(

[ddorwin, 2016/03/18 20:38:53]

I think you need to put all this code in a separate function that Gets all CDM
Modules. You'll eventually need it for preloading CDMs before sandboxing once
Pepper CDMs are disabled (unless we do per-CDM loading, in which case there will
need to be more specific functions). This method would call that function on
desktop. (There might be some abstraction that complicates things a bit. I'll
explain offline.)

This is similar to how AddPepperPlugins() calls ComputeBuiltInPlugins(), which
is used in sandboxing and perhaps elsewhere.

[jrummell, 2016/03/23 21:38:09]

Added RegisterAllAvailableCdms() that will call AddContentDecryptionModules() to
make it explicit.

+    std::vector<content::CdmInfo>* modules) {
+#if defined(WIDEVINE_CDM_AVAILABLE) && !defined(WIDEVINE_CDM_IS_COMPONENT)
+  base::FilePath widevine_adapter_path;
+  std::vector<base::string16> codecs_supported;
+  std::vector<base::string16> supported_init_data_types;
+  if (IsWidevineAvailable(&widevine_adapter_path, &codecs_supported,
+                          &supported_init_data_types)) {
+    // |key_systems| needs |path| to be the actual Widevine library,
+    // not the adapter, so adjust as necessary. It will be in the
+    // same directory as the installed adapter.
+    modules->push_back(content::CdmInfo(
+        kWidevineKeySystem, WIDEVINE_CDM_VERSION_STRING,
+        widevine_adapter_path.DirName().AppendASCII(kWidevineCdmFileName),

[ddorwin, 2016/03/18 19:24:17]

This line should be a separate statement under the comment above. The comment
does not describe the entire statement, and this is fairly complex to inline.

[jrummell, 2016/03/23 21:38:09]

Done.

+        codecs_supported, supported_init_data_types));
+  }
+#endif  // defined(WIDEVINE_CDM_AVAILABLE) &&
+        // !defined(WIDEVINE_CDM_IS_COMPONENT)
+}

[ddorwin, 2016/03/18 19:24:18]

TODO: Add ECK?

[jrummell, 2016/03/23 21:38:09]

Done.

+
 #if defined(OS_CHROMEOS)
 static const int kNumChromeStandardURLSchemes = 6;
 #else