Source/WebCore/Modules/encryptedmedia/legacy/WebKitMediaKeySession.cpp - WebKit - Git at Google

 /*
  * Copyright (C) 2013 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
  * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
  * THE POSSIBILITY OF SUCH DAMAGE.
  */

 #include "config.h"
 #include "WebKitMediaKeySession.h"

 #if ENABLE(LEGACY_ENCRYPTED_MEDIA)

 #include "Document.h"
 #include "EventNames.h"
 #include "Page.h"
 #include "SecurityOriginData.h"
 #include "Settings.h"
 #include "WebKitMediaKeyError.h"
 #include "WebKitMediaKeyMessageEvent.h"
 #include "WebKitMediaKeys.h"
 #include <wtf/FileSystem.h>
 #include <wtf/IsoMallocInlines.h>

 namespace WebCore {

 WTF_MAKE_ISO_ALLOCATED_IMPL(WebKitMediaKeySession);

 Ref<WebKitMediaKeySession> WebKitMediaKeySession::create(ScriptExecutionContext& context, WebKitMediaKeys& keys, const String& keySystem)
 {
     auto session = adoptRef(*new WebKitMediaKeySession(context, keys, keySystem));
     session->suspendIfNeeded();
     return session;
 }

 WebKitMediaKeySession::WebKitMediaKeySession(ScriptExecutionContext& context, WebKitMediaKeys& keys, const String& keySystem)
     : ActiveDOMObject(&context)
     , m_keys(&keys)
     , m_keySystem(keySystem)
     , m_asyncEventQueue(MainThreadGenericEventQueue::create(*this))
     , m_session(keys.cdm().createSession(*this))
     , m_keyRequestTimer(*this, &WebKitMediaKeySession::keyRequestTimerFired)
     , m_addKeyTimer(*this, &WebKitMediaKeySession::addKeyTimerFired)
 {
     if (m_session)
         m_sessionId = m_session->sessionId();
 }

 WebKitMediaKeySession::~WebKitMediaKeySession()
 {
     if (m_session)
         m_session->setClient(nullptr);

     m_asyncEventQueue->cancelAllEvents();
 }

 void WebKitMediaKeySession::close()
 {
     if (m_session) {
         m_session->releaseKeys();
         m_session = nullptr;
     }
 }

 RefPtr<ArrayBuffer> WebKitMediaKeySession::cachedKeyForKeyId(const String& keyId) const
 {
     return m_session ? m_session->cachedKeyForKeyID(keyId) : nullptr;
 }

 void WebKitMediaKeySession::generateKeyRequest(const String& mimeType, Ref<Uint8Array>&& initData)
 {
     m_pendingKeyRequests.append({ mimeType, WTFMove(initData) });
     m_keyRequestTimer.startOneShot(0_s);
 }

 void WebKitMediaKeySession::keyRequestTimerFired()
 {
     ASSERT(m_pendingKeyRequests.size());
     if (!m_session)
         return;

     while (!m_pendingKeyRequests.isEmpty()) {
         auto request = m_pendingKeyRequests.takeFirst();

         // NOTE: Continued from step 5 in MediaKeys::createSession().
         // The user agent will asynchronously execute the following steps in the task:

         // 1. Let cdm be the cdm loaded in the MediaKeys constructor.
         // 2. Let destinationURL be null.
         String destinationURL;
         WebKitMediaKeyError::Code errorCode = 0;
         uint32_t systemCode = 0;

         // 3. Use cdm to generate a key request and follow the steps for the first matching condition from the following list:

         auto keyRequest = m_session->generateKeyRequest(request.mimeType, request.initData.ptr(), destinationURL, errorCode, systemCode);

         // Otherwise [if a request is not successfully generated]:
         if (errorCode) {
             // 3.1. Create a new MediaKeyError object with the following attributes:
             //      code = the appropriate MediaKeyError code
             //      systemCode = a Key System-specific value, if provided, and 0 otherwise
             // 3.2. Set the MediaKeySession object's error attribute to the error object created in the previous step.
             // 3.3. queue a task to fire a simple event named keyerror at the MediaKeySession object.
             sendError(errorCode, systemCode);
             // 3.4. Abort the task.
             continue;
         }

         // 4. queue a task to fire a simple event named keymessage at the new object
         //    The event is of type MediaKeyMessageEvent and has:
         //    message = key request
         //    destinationURL = destinationURL
         if (keyRequest)
             sendMessage(keyRequest.get(), destinationURL);
     }
 }

 ExceptionOr<void> WebKitMediaKeySession::update(Ref<Uint8Array>&& key)
 {
     // From <http://dvcs.w3.org/hg/html-media/raw-file/tip/encrypted-media/encrypted-media.html#dom-addkey>:
     // The addKey(key) method must run the following steps:
     // 1. If the first or second argument [sic] is an empty array, throw an InvalidAccessError.
     // NOTE: the reference to a "second argument" is a spec bug.
     if (!key->length())
         return Exception { InvalidAccessError };

     // 2. Schedule a task to handle the call, providing key.
     m_pendingKeys.append(WTFMove(key));
     m_addKeyTimer.startOneShot(0_s);

     return { };
 }

 void WebKitMediaKeySession::addKeyTimerFired()
 {
     ASSERT(m_pendingKeys.size());
     if (!m_session)
         return;

     while (!m_pendingKeys.isEmpty()) {
         auto pendingKey = m_pendingKeys.takeFirst();
         unsigned short errorCode = 0;
         uint32_t systemCode = 0;

         // NOTE: Continued from step 2. of MediaKeySession::update()
         // 2.1. Let cdm be the cdm loaded in the MediaKeys constructor.
         // NOTE: This is m_session.
         // 2.2. Let 'did store key' be false.
         bool didStoreKey = false;
         // 2.3. Let 'next message' be null.
         RefPtr<Uint8Array> nextMessage;
         // 2.4. Use cdm to handle key.
         didStoreKey = m_session->update(pendingKey.ptr(), nextMessage, errorCode, systemCode);
         // 2.5. If did store key is true and the media element is waiting for a key, queue a task to attempt to resume playback.
         // TODO: Find and restart the media element

         // 2.6. If next message is not null, queue a task to fire a simple event named keymessage at the MediaKeySession object.
         //      The event is of type MediaKeyMessageEvent and has:
         //      message = next message
         //      destinationURL = null
         if (nextMessage)
             sendMessage(nextMessage.get(), emptyString());

         // 2.7. If did store key is true, queue a task to fire a simple event named keyadded at the MediaKeySession object.
         if (didStoreKey) {
             auto keyaddedEvent = Event::create(eventNames().webkitkeyaddedEvent, Event::CanBubble::No, Event::IsCancelable::No);
             keyaddedEvent->setTarget(this);
             m_asyncEventQueue->enqueueEvent(WTFMove(keyaddedEvent));

             ASSERT(m_keys);
             m_keys->keyAdded();
         }

         // 2.8. If any of the preceding steps in the task failed
         if (errorCode) {
             // 2.8.1. Create a new MediaKeyError object with the following attributes:
             //        code = the appropriate MediaKeyError code
             //        systemCode = a Key System-specific value, if provided, and 0 otherwise
             // 2.8.2. Set the MediaKeySession object's error attribute to the error object created in the previous step.
             // 2.8.3. queue a task to fire a simple event named keyerror at the MediaKeySession object.
             sendError(errorCode, systemCode);
             // 2.8.4. Abort the task.
             // NOTE: no-op
         }
     }
 }

 void WebKitMediaKeySession::sendMessage(Uint8Array* message, String destinationURL)
 {
     auto event = WebKitMediaKeyMessageEvent::create(eventNames().webkitkeymessageEvent, message, destinationURL);
     event->setTarget(this);
     m_asyncEventQueue->enqueueEvent(WTFMove(event));
 }

 void WebKitMediaKeySession::sendError(MediaKeyErrorCode errorCode, uint32_t systemCode)
 {
     m_error = WebKitMediaKeyError::create(errorCode, systemCode);

     auto keyerrorEvent = Event::create(eventNames().webkitkeyerrorEvent, Event::CanBubble::No, Event::IsCancelable::No);
     keyerrorEvent->setTarget(this);
     m_asyncEventQueue->enqueueEvent(WTFMove(keyerrorEvent));
 }

 String WebKitMediaKeySession::mediaKeysStorageDirectory() const
 {
     auto* document = downcast<Document>(scriptExecutionContext());
     if (!document)
         return emptyString();

     auto* page = document->page();
     if (!page || page->usesEphemeralSession())
         return emptyString();

     auto storageDirectory = document->settings().mediaKeysStorageDirectory();
     if (storageDirectory.isEmpty())
         return emptyString();

     return FileSystem::pathByAppendingComponent(storageDirectory, document->securityOrigin().data().databaseIdentifier());
 }

 bool WebKitMediaKeySession::hasPendingActivity() const
 {
     return (m_keys && m_session) || m_asyncEventQueue->hasPendingEvents();
 }

 void WebKitMediaKeySession::stop()
 {
     close();
 }

 const char* WebKitMediaKeySession::activeDOMObjectName() const
 {
     return "WebKitMediaKeySession";
 }

 bool WebKitMediaKeySession::shouldPreventEnteringBackForwardCache_DEPRECATED() const
 {
     // FIXME: This should never prevent entering the back/forward cache.
     return true;
 }

 }

 #endif
	/*
	* Copyright (C) 2013 Apple Inc. All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution.
	*
	* THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
	* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
	* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
	* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
	* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
	* THE POSSIBILITY OF SUCH DAMAGE.
	*/

	#include "config.h"
	#include "WebKitMediaKeySession.h"

	#if ENABLE(LEGACY_ENCRYPTED_MEDIA)

	#include "Document.h"
	#include "EventNames.h"
	#include "Page.h"
	#include "SecurityOriginData.h"
	#include "Settings.h"
	#include "WebKitMediaKeyError.h"
	#include "WebKitMediaKeyMessageEvent.h"
	#include "WebKitMediaKeys.h"
	#include <wtf/FileSystem.h>
	#include <wtf/IsoMallocInlines.h>

	namespace WebCore {

	WTF_MAKE_ISO_ALLOCATED_IMPL(WebKitMediaKeySession);

	Ref<WebKitMediaKeySession> WebKitMediaKeySession::create(ScriptExecutionContext& context, WebKitMediaKeys& keys, const String& keySystem)
	{
	auto session = adoptRef(*new WebKitMediaKeySession(context, keys, keySystem));
	session->suspendIfNeeded();
	return session;
	}

	WebKitMediaKeySession::WebKitMediaKeySession(ScriptExecutionContext& context, WebKitMediaKeys& keys, const String& keySystem)
	: ActiveDOMObject(&context)
	, m_keys(&keys)
	, m_keySystem(keySystem)
	, m_asyncEventQueue(MainThreadGenericEventQueue::create(*this))
	, m_session(keys.cdm().createSession(*this))
	, m_keyRequestTimer(*this, &WebKitMediaKeySession::keyRequestTimerFired)
	, m_addKeyTimer(*this, &WebKitMediaKeySession::addKeyTimerFired)
	{
	if (m_session)
	m_sessionId = m_session->sessionId();
	}

	WebKitMediaKeySession::~WebKitMediaKeySession()
	{
	if (m_session)
	m_session->setClient(nullptr);

	m_asyncEventQueue->cancelAllEvents();
	}

	void WebKitMediaKeySession::close()
	{
	if (m_session) {
	m_session->releaseKeys();
	m_session = nullptr;
	}
	}

	RefPtr<ArrayBuffer> WebKitMediaKeySession::cachedKeyForKeyId(const String& keyId) const
	{
	return m_session ? m_session->cachedKeyForKeyID(keyId) : nullptr;
	}

	void WebKitMediaKeySession::generateKeyRequest(const String& mimeType, Ref<Uint8Array>&& initData)
	{
	m_pendingKeyRequests.append({ mimeType, WTFMove(initData) });
	m_keyRequestTimer.startOneShot(0_s);
	}

	void WebKitMediaKeySession::keyRequestTimerFired()
	{
	ASSERT(m_pendingKeyRequests.size());
	if (!m_session)
	return;

	while (!m_pendingKeyRequests.isEmpty()) {
	auto request = m_pendingKeyRequests.takeFirst();

	// NOTE: Continued from step 5 in MediaKeys::createSession().
	// The user agent will asynchronously execute the following steps in the task:

	// 1. Let cdm be the cdm loaded in the MediaKeys constructor.
	// 2. Let destinationURL be null.
	String destinationURL;
	WebKitMediaKeyError::Code errorCode = 0;
	uint32_t systemCode = 0;

	// 3. Use cdm to generate a key request and follow the steps for the first matching condition from the following list:

	auto keyRequest = m_session->generateKeyRequest(request.mimeType, request.initData.ptr(), destinationURL, errorCode, systemCode);

	// Otherwise [if a request is not successfully generated]:
	if (errorCode) {
	// 3.1. Create a new MediaKeyError object with the following attributes:
	// code = the appropriate MediaKeyError code
	// systemCode = a Key System-specific value, if provided, and 0 otherwise
	// 3.2. Set the MediaKeySession object's error attribute to the error object created in the previous step.
	// 3.3. queue a task to fire a simple event named keyerror at the MediaKeySession object.
	sendError(errorCode, systemCode);
	// 3.4. Abort the task.
	continue;
	}

	// 4. queue a task to fire a simple event named keymessage at the new object
	// The event is of type MediaKeyMessageEvent and has:
	// message = key request
	// destinationURL = destinationURL
	if (keyRequest)
	sendMessage(keyRequest.get(), destinationURL);
	}
	}

	ExceptionOr<void> WebKitMediaKeySession::update(Ref<Uint8Array>&& key)
	{
	// From <http://dvcs.w3.org/hg/html-media/raw-file/tip/encrypted-media/encrypted-media.html#dom-addkey>:
	// The addKey(key) method must run the following steps:
	// 1. If the first or second argument [sic] is an empty array, throw an InvalidAccessError.
	// NOTE: the reference to a "second argument" is a spec bug.
	if (!key->length())
	return Exception { InvalidAccessError };

	// 2. Schedule a task to handle the call, providing key.
	m_pendingKeys.append(WTFMove(key));
	m_addKeyTimer.startOneShot(0_s);

	return { };
	}

	void WebKitMediaKeySession::addKeyTimerFired()
	{
	ASSERT(m_pendingKeys.size());
	if (!m_session)
	return;

	while (!m_pendingKeys.isEmpty()) {
	auto pendingKey = m_pendingKeys.takeFirst();
	unsigned short errorCode = 0;
	uint32_t systemCode = 0;

	// NOTE: Continued from step 2. of MediaKeySession::update()
	// 2.1. Let cdm be the cdm loaded in the MediaKeys constructor.
	// NOTE: This is m_session.
	// 2.2. Let 'did store key' be false.
	bool didStoreKey = false;
	// 2.3. Let 'next message' be null.
	RefPtr<Uint8Array> nextMessage;
	// 2.4. Use cdm to handle key.
	didStoreKey = m_session->update(pendingKey.ptr(), nextMessage, errorCode, systemCode);
	// 2.5. If did store key is true and the media element is waiting for a key, queue a task to attempt to resume playback.
	// TODO: Find and restart the media element

	// 2.6. If next message is not null, queue a task to fire a simple event named keymessage at the MediaKeySession object.
	// The event is of type MediaKeyMessageEvent and has:
	// message = next message
	// destinationURL = null
	if (nextMessage)
	sendMessage(nextMessage.get(), emptyString());

	// 2.7. If did store key is true, queue a task to fire a simple event named keyadded at the MediaKeySession object.
	if (didStoreKey) {
	auto keyaddedEvent = Event::create(eventNames().webkitkeyaddedEvent, Event::CanBubble::No, Event::IsCancelable::No);
	keyaddedEvent->setTarget(this);
	m_asyncEventQueue->enqueueEvent(WTFMove(keyaddedEvent));

	ASSERT(m_keys);
	m_keys->keyAdded();
	}

	// 2.8. If any of the preceding steps in the task failed
	if (errorCode) {
	// 2.8.1. Create a new MediaKeyError object with the following attributes:
	// code = the appropriate MediaKeyError code
	// systemCode = a Key System-specific value, if provided, and 0 otherwise
	// 2.8.2. Set the MediaKeySession object's error attribute to the error object created in the previous step.
	// 2.8.3. queue a task to fire a simple event named keyerror at the MediaKeySession object.
	sendError(errorCode, systemCode);
	// 2.8.4. Abort the task.
	// NOTE: no-op
	}
	}
	}

	void WebKitMediaKeySession::sendMessage(Uint8Array* message, String destinationURL)
	{
	auto event = WebKitMediaKeyMessageEvent::create(eventNames().webkitkeymessageEvent, message, destinationURL);
	event->setTarget(this);
	m_asyncEventQueue->enqueueEvent(WTFMove(event));
	}

	void WebKitMediaKeySession::sendError(MediaKeyErrorCode errorCode, uint32_t systemCode)
	{
	m_error = WebKitMediaKeyError::create(errorCode, systemCode);

	auto keyerrorEvent = Event::create(eventNames().webkitkeyerrorEvent, Event::CanBubble::No, Event::IsCancelable::No);
	keyerrorEvent->setTarget(this);
	m_asyncEventQueue->enqueueEvent(WTFMove(keyerrorEvent));
	}

	String WebKitMediaKeySession::mediaKeysStorageDirectory() const
	{
	auto* document = downcast<Document>(scriptExecutionContext());
	if (!document)
	return emptyString();

	auto* page = document->page();
	if (!page \|\| page->usesEphemeralSession())
	return emptyString();

	auto storageDirectory = document->settings().mediaKeysStorageDirectory();
	if (storageDirectory.isEmpty())
	return emptyString();

	return FileSystem::pathByAppendingComponent(storageDirectory, document->securityOrigin().data().databaseIdentifier());
	}

	bool WebKitMediaKeySession::hasPendingActivity() const
	{
	return (m_keys && m_session) \|\| m_asyncEventQueue->hasPendingEvents();
	}

	void WebKitMediaKeySession::stop()
	{
	close();
	}

	const char* WebKitMediaKeySession::activeDOMObjectName() const
	{
	return "WebKitMediaKeySession";
	}

	bool WebKitMediaKeySession::shouldPreventEnteringBackForwardCache_DEPRECATED() const
	{
	// FIXME: This should never prevent entering the back/forward cache.
	return true;
	}

	}

	#endif