Add PPAPI decryptor implementation.

ppapi/proxy/ppp_content_decryptor_private_proxy.cc

+// Copyright (c) 2012 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 "ppapi/proxy/ppp_content_decryptor_private_proxy.h"
+
+#include "base/platform_file.h"
+#include "ppapi/c/pp_bool.h"
+#include "ppapi/c/ppb_core.h"
+#include "ppapi/proxy/host_dispatcher.h"
+#include "ppapi/proxy/plugin_globals.h"
+#include "ppapi/proxy/plugin_resource_tracker.h"
+#include "ppapi/proxy/ppapi_messages.h"
+#include "ppapi/proxy/ppb_buffer_proxy.h"
+#include "ppapi/proxy/serialized_var.h"
+#include "ppapi/shared_impl/var_tracker.h"
+#include "ppapi/thunk/enter.h"
+#include "ppapi/thunk/ppb_buffer_api.h"
+#include "ppapi/thunk/ppb_buffer_trusted_api.h"
+#include "ppapi/thunk/ppb_instance_api.h"
+#include "ppapi/thunk/thunk.h"
+
+using ppapi::thunk::EnterResourceNoLock;
+using ppapi::thunk::PPB_Buffer_API;
+using ppapi::thunk::PPB_BufferTrusted_API;
+using ppapi::thunk::PPB_Instance_API;
+
+namespace ppapi {
+namespace proxy {
+
+namespace {
+
+PP_Bool DescribeHostBufferResource(PP_Resource resource, uint32_t* size) {
+  EnterResourceNoLock<PPB_Buffer_API> enter(resource, true);
+  if (enter.failed())
+    return PP_FALSE;
+  return enter.object()->Describe(size);
+}
+
+// TODO(dmichael): Refactor so this handle sharing code is in one place.
+PP_Bool ShareHostBufferResourceToPlugin(
+    HostDispatcher* dispatcher,
+    PP_Resource resource,
+    base::SharedMemoryHandle* shared_mem_handle) {
+  if (!dispatcher || resource == 0 || !shared_mem_handle)
+    return PP_FALSE;
+  EnterResourceNoLock<PPB_BufferTrusted_API> enter(resource, true);
+  if (enter.failed())
+    return PP_FALSE;
+  int handle;
+  int32_t result = enter.object()->GetSharedMemory(&handle);
+  if (result != PP_OK)
+    return PP_FALSE;
+  base::PlatformFile platform_file =
+  #if defined(OS_WIN)
+      reinterpret_cast<HANDLE>(static_cast<intptr_t>(handle));
+  #elif defined(OS_POSIX)
+      handle;
+  #else
+  #error Not implemented.
+  #endif
+
+  *shared_mem_handle = dispatcher->ShareHandleWithRemote(platform_file, false);
+  return PP_TRUE;
+}
+
+// SerializedVarReceiveInput will decrement the reference count, but we want
+// to give the recipient a reference. This utility function takes care of that
+// work for the message handlers defined below.
+PP_Var ExtractReceivedVarAndAddRef(Dispatcher* dispatcher,
+                                   SerializedVarReceiveInput* serialized_var) {
+  PP_Var var = serialized_var->Get(dispatcher);
+  PpapiGlobals::Get()->GetVarTracker()->AddRefVar(var);
+  return var;
+}
+
+PP_Bool GenerateKeyRequest(PP_Instance instance,
+                           PP_Var key_system,
+                           PP_Var init_data) {
+  HostDispatcher* dispatcher = HostDispatcher::GetForInstance(instance);
+  if (!dispatcher) {
+    NOTREACHED();
+    return PP_FALSE;
+  }
+
+  return PP_FromBool(dispatcher->Send(
+      new PpapiMsg_PPPContentDecryptor_GenerateKeyRequest(
+          API_ID_PPP_CONTENT_DECRYPTOR_PRIVATE,
+          instance,
+          SerializedVarSendInput(dispatcher, key_system),
+          SerializedVarSendInput(dispatcher, init_data))));
+}
+
+PP_Bool AddKey(PP_Instance instance,
+               PP_Var session_id,
+               PP_Var key) {
+  HostDispatcher* dispatcher = HostDispatcher::GetForInstance(instance);
+  if (!dispatcher) {
+    NOTREACHED();
+    return PP_FALSE;
+  }
+
+  return PP_FromBool(dispatcher->Send(
+      new PpapiMsg_PPPContentDecryptor_AddKey(
+          API_ID_PPP_CONTENT_DECRYPTOR_PRIVATE,
+          instance,
+          SerializedVarSendInput(dispatcher, session_id),
+          SerializedVarSendInput(dispatcher, key))));
+}
+
+PP_Bool CancelKeyRequest(PP_Instance instance, PP_Var session_id) {
+  HostDispatcher* dispatcher = HostDispatcher::GetForInstance(instance);
+  if (!dispatcher) {
+    NOTREACHED();
+    return PP_FALSE;
+  }
+
+  return PP_FromBool(dispatcher->Send(
+      new PpapiMsg_PPPContentDecryptor_CancelKeyRequest(
+          API_ID_PPP_CONTENT_DECRYPTOR_PRIVATE,
+          instance,
+          SerializedVarSendInput(dispatcher, session_id))));
+}
+
+PP_Bool Decrypt(PP_Instance instance,
+                PP_Resource encrypted_block,
+                int32_t request_id) {
+  HostDispatcher* dispatcher = HostDispatcher::GetForInstance(instance);
+  if (!dispatcher) {
+    NOTREACHED();
+    return PP_FALSE;
+  }
+  const PPB_Core* core = static_cast<const PPB_Core*>(
+      dispatcher->local_get_interface()(PPB_CORE_INTERFACE));
+  if (!core) {
+    NOTREACHED();
+    return PP_FALSE;
+  }
+
+  // We need to take a ref on the resource now. The browser may drop
+  // references once we return from here, but we're sending an asynchronous
+  // message. The plugin side takes ownership of that reference.
+  core->AddRefResource(encrypted_block);
+
+  HostResource host_resource;
+  host_resource.SetHostResource(instance, encrypted_block);
+
+  uint32_t size = 0;
+  if (DescribeHostBufferResource(encrypted_block, &size) == PP_FALSE)
+    return PP_FALSE;
+
+  base::SharedMemoryHandle handle;
+  if (ShareHostBufferResourceToPlugin(dispatcher,
+                                      encrypted_block,
+                                      &handle) == PP_FALSE)
+    return PP_FALSE;
+
+  PPPDecryptor_Buffer buffer;
+  buffer.resource = host_resource;
+  buffer.handle = handle;
+  buffer.size = size;
+
+  return PP_FromBool(dispatcher->Send(
+      new PpapiMsg_PPPContentDecryptor_Decrypt(
+          API_ID_PPP_CONTENT_DECRYPTOR_PRIVATE,
+          instance,
+          buffer,
+          request_id)));
+}
+
+PP_Bool DecryptAndDecode(PP_Instance instance,
+                         PP_Resource encrypted_block,
+                         int32_t request_id) {
+  HostDispatcher* dispatcher = HostDispatcher::GetForInstance(instance);
+  if (!dispatcher) {
+    NOTREACHED();
+    return PP_FALSE;
+  }
+
+  HostResource host_resource;
+  host_resource.SetHostResource(instance, encrypted_block);
+
+  return PP_FromBool(dispatcher->Send(
+      new PpapiMsg_PPPContentDecryptor_DecryptAndDecode(
+          API_ID_PPP_CONTENT_DECRYPTOR_PRIVATE,
+          instance,
+          host_resource,
+          request_id)));
+}
+
+static const PPP_ContentDecryptor_Private content_decryptor_interface = {
+  &GenerateKeyRequest,
+  &AddKey,
+  &CancelKeyRequest,
+  &Decrypt,
+  &DecryptAndDecode
+};
+
+InterfaceProxy* CreateContentDecryptorPPPProxy(Dispatcher* dispatcher) {
+  return new PPP_ContentDecryptor_Private_Proxy(dispatcher);
+}
+
+}  // namespace
+
+PPP_ContentDecryptor_Private_Proxy::PPP_ContentDecryptor_Private_Proxy(
+    Dispatcher* dispatcher)
+    : InterfaceProxy(dispatcher),
+      ppp_decryptor_impl_(NULL) {
+  if (dispatcher->IsPlugin()) {
+    ppp_decryptor_impl_ = static_cast<const PPP_ContentDecryptor_Private*>(
+        dispatcher->local_get_interface()(
+            PPP_CONTENTDECRYPTOR_PRIVATE_INTERFACE));
+  }
+}
+
+PPP_ContentDecryptor_Private_Proxy::~PPP_ContentDecryptor_Private_Proxy() {
+}
+
+// static
+const PPP_ContentDecryptor_Private*
+    PPP_ContentDecryptor_Private_Proxy::GetProxyInterface() {
+  return &content_decryptor_interface;
+}
+
+bool PPP_ContentDecryptor_Private_Proxy::OnMessageReceived(
+    const IPC::Message& msg) {
+  bool handled = true;
+  IPC_BEGIN_MESSAGE_MAP(PPP_ContentDecryptor_Private_Proxy, msg)
+    IPC_MESSAGE_HANDLER(PpapiMsg_PPPContentDecryptor_GenerateKeyRequest,
+                        OnMsgGenerateKeyRequest)
+    IPC_MESSAGE_HANDLER(PpapiMsg_PPPContentDecryptor_AddKey,
+                        OnMsgAddKey)
+    IPC_MESSAGE_HANDLER(PpapiMsg_PPPContentDecryptor_CancelKeyRequest,
+                        OnMsgCancelKeyRequest)
+    IPC_MESSAGE_HANDLER(PpapiMsg_PPPContentDecryptor_Decrypt,
+                        OnMsgDecrypt)
+    IPC_MESSAGE_HANDLER(PpapiMsg_PPPContentDecryptor_DecryptAndDecode,
+                        OnMsgDecryptAndDecode)
+    IPC_MESSAGE_UNHANDLED(handled = false)
+  IPC_END_MESSAGE_MAP()
+  DCHECK(handled);
+  return handled;
+}
+
+void PPP_ContentDecryptor_Private_Proxy::OnMsgGenerateKeyRequest(
+    PP_Instance instance,
+    SerializedVarReceiveInput key_system,
+    SerializedVarReceiveInput init_data) {
+  if (ppp_decryptor_impl_) {
+    CallWhileUnlocked(ppp_decryptor_impl_->GenerateKeyRequest,
+                      instance,
+                      ExtractReceivedVarAndAddRef(dispatcher(), &key_system),
+                      ExtractReceivedVarAndAddRef(dispatcher(), &init_data));
+  }
+}
+
+void PPP_ContentDecryptor_Private_Proxy::OnMsgAddKey(
+    PP_Instance instance,
+    SerializedVarReceiveInput session_id,
+    SerializedVarReceiveInput key) {
+  if (ppp_decryptor_impl_) {
+    CallWhileUnlocked(ppp_decryptor_impl_->AddKey,
+                      instance,
+                      ExtractReceivedVarAndAddRef(dispatcher(), &session_id),
+                      ExtractReceivedVarAndAddRef(dispatcher(), &key));
+  }
+}
+
+void PPP_ContentDecryptor_Private_Proxy::OnMsgCancelKeyRequest(
+    PP_Instance instance,
+    SerializedVarReceiveInput session_id) {
+  if (ppp_decryptor_impl_) {
+    CallWhileUnlocked(ppp_decryptor_impl_->CancelKeyRequest,
+                      instance,
+                      ExtractReceivedVarAndAddRef(dispatcher(), &session_id));
+  }
+}
+
+void PPP_ContentDecryptor_Private_Proxy::OnMsgDecrypt(
+    PP_Instance instance,
+    const PPPDecryptor_Buffer& encrypted_buffer,
+    int32_t request_id) {
+  if (ppp_decryptor_impl_) {
+    PP_Resource plugin_resource =
+        PPB_Buffer_Proxy::AddProxyResource(encrypted_buffer.resource,
+                                           encrypted_buffer.handle,
+                                           encrypted_buffer.size);
+    CallWhileUnlocked(ppp_decryptor_impl_->Decrypt,
+                      instance,
+                      plugin_resource,
+                      request_id);
+  }
+}
+
+void PPP_ContentDecryptor_Private_Proxy::OnMsgDecryptAndDecode(
+    PP_Instance instance,
+    const HostResource& encrypted_block,
+    int32_t request_id) {
+  if (ppp_decryptor_impl_) {
+    PP_Resource plugin_resource =
+        PluginGlobals::Get()->plugin_resource_tracker()->
+            PluginResourceForHostResource(encrypted_block);
+    CallWhileUnlocked(ppp_decryptor_impl_->DecryptAndDecode,
+                      instance,
+                      plugin_resource,
+                      request_id);
+  }
+}
+
+}  // namespace proxy
+}  // namespace ppapi