/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "AutoplayPolicy.h"
#include "mozilla/dom/AudioContext.h"
#include "mozilla/dom/Document.h"
#include "mozilla/dom/FeaturePolicyUtils.h"
#include "mozilla/dom/HTMLMediaElement.h"
#include "mozilla/dom/HTMLMediaElementBinding.h"
#include "mozilla/dom/NavigatorBinding.h"
#include "mozilla/dom/UserActivation.h"
#include "mozilla/dom/WindowContext.h"
#include "mozilla/Logging.h"
#include "mozilla/MediaManager.h"
#include "mozilla/Components.h"
#include "mozilla/StaticPrefs_media.h"
#include "nsContentUtils.h"
#include "nsGlobalWindowInner.h"
#include "nsIAutoplay.h"
#include "nsIDocShell.h"
#include "nsIDocShellTreeItem.h"
#include "nsIPermissionManager.h"
#include "nsIPrincipal.h"
#include "nsPIDOMWindow.h"
mozilla::LazyLogModule gAutoplayPermissionLog(
"Autoplay");
#define AUTOPLAY_LOG(msg, ...) \
MOZ_LOG(gAutoplayPermissionLog, LogLevel::Debug, (msg,
##__VA_ARGS__))
using namespace mozilla::dom;
namespace mozilla::media {
static const uint32_t sPOLICY_STICKY_ACTIVATION = 0;
// static const uint32_t sPOLICY_TRANSIENT_ACTIVATION = 1;
static const uint32_t sPOLICY_USER_INPUT_DEPTH = 2;
static bool IsActivelyCapturingOrHasAPermission(nsPIDOMWindowInner* aWindow) {
// Pages which have been granted permission to capture WebRTC camera or
// microphone or screen are assumed to be trusted, and are allowed to
// autoplay.
if (MediaManager::GetIfExists()) {
return MediaManager::GetIfExists()->IsActivelyCapturingOrHasAPermission(
aWindow->WindowID());
}
auto principal = nsGlobalWindowInner::Cast(aWindow)->GetPrincipal();
return (nsContentUtils::IsExactSitePermAllow(principal,
"camera"_ns) ||
nsContentUtils::IsExactSitePermAllow(principal,
"microphone"_ns) ||
nsContentUtils::IsExactSitePermAllow(principal,
"screen"_ns));
}
static uint32_t SiteAutoplayPerm(nsPIDOMWindowInner* aWindow) {
if (!aWindow || !aWindow->GetBrowsingContext()) {
return nsIPermissionManager::UNKNOWN_ACTION;
}
WindowContext* topContext =
aWindow->GetBrowsingContext()->GetTopWindowContext();
if (!topContext) {
return nsIPermissionManager::UNKNOWN_ACTION;
}
return topContext->GetAutoplayPermission();
}
static bool IsWindowAllowedToPlayByUserGesture(nsPIDOMWindowInner* aWindow) {
if (!aWindow) {
return false;
}
WindowContext* topContext =
aWindow->GetBrowsingContext()->GetTopWindowContext();
if (topContext && topContext->HasBeenUserGestureActivated()) {
AUTOPLAY_LOG(
"Allow autoplay as top-level context has been activated by user "
"gesture.");
return true;
}
return false;
}
static bool IsWindowAllowedToPlayByTraits(nsPIDOMWindowInner* aWindow) {
if (!aWindow) {
return false;
}
if (IsActivelyCapturingOrHasAPermission(aWindow)) {
AUTOPLAY_LOG(
"Allow autoplay as document has camera or microphone or screen"
" permission.");
return true;
}
Document* currentDoc = aWindow->GetExtantDoc();
if (!currentDoc) {
return false;
}
bool isTopLevelContent = !aWindow->GetBrowsingContext()->GetParent();
if (currentDoc->MediaDocumentKind() == Document::MediaDocumentKind::Video &&
isTopLevelContent) {
AUTOPLAY_LOG(
"Allow top-level video document to autoplay.");
return true;
}
if (StaticPrefs::media_autoplay_allow_extension_background_pages() &&
currentDoc->IsExtensionPage()) {
AUTOPLAY_LOG(
"Allow autoplay as in extension document.");
return true;
}
if (currentDoc->GetPrincipal()->Equals(
nsContentUtils::GetFingerprintingProtectionPrincipal())) {
AUTOPLAY_LOG(
"Allow autoplay as in fingerprinting protection document.");
return true;
}
return false;
}
static bool IsWindowAllowedToPlayOverall(nsPIDOMWindowInner* aWindow) {
return IsWindowAllowedToPlayByUserGesture(aWindow) ||
IsWindowAllowedToPlayByTraits(aWindow);
}
static uint32_t DefaultAutoplayBehaviour() {
int32_t prefValue = StaticPrefs::media_autoplay_default();
if (prefValue == nsIAutoplay::ALLOWED) {
return nsIAutoplay::ALLOWED;
}
if (prefValue == nsIAutoplay::BLOCKED_ALL) {
return nsIAutoplay::BLOCKED_ALL;
}
return nsIAutoplay::BLOCKED;
}
static bool IsMediaElementInaudible(
const HTMLMediaElement& aElement) {
if (aElement.Volume() == 0.0 || aElement.Muted()) {
AUTOPLAY_LOG(
"Media %p is muted.", &aElement);
return true;
}
if (!aElement.HasAudio() &&
aElement.ReadyState() >= HTMLMediaElement_Binding::HAVE_METADATA) {
AUTOPLAY_LOG(
"Media %p has no audio track", &aElement);
return true;
}
return false;
}
static bool IsEnableBlockingWebAudioByUserGesturePolicy() {
return StaticPrefs::media_autoplay_blocking_policy() ==
sPOLICY_STICKY_ACTIVATION;
}
static bool IsAllowedToPlayByBlockingModel(
const HTMLMediaElement& aElement) {
const uint32_t policy = StaticPrefs::media_autoplay_blocking_policy();
if (policy == sPOLICY_STICKY_ACTIVATION) {
const bool isAllowed =
IsWindowAllowedToPlayOverall(aElement.OwnerDoc()->GetInnerWindow());
AUTOPLAY_LOG(
"Use 'sticky-activation', isAllowed=%d", isAllowed);
return isAllowed;
}
// If element is blessed, it would always be allowed to play().
const bool isElementBlessed = aElement.IsBlessed();
if (policy == sPOLICY_USER_INPUT_DEPTH) {
const bool isUserInput = UserActivation::IsHandlingUserInput();
AUTOPLAY_LOG(
"Use 'User-Input-Depth', isBlessed=%d, isUserInput=%d",
isElementBlessed, isUserInput);
return isElementBlessed || isUserInput;
}
const bool hasTransientActivation =
aElement.OwnerDoc()->HasValidTransientUserGestureActivation();
AUTOPLAY_LOG(
"Use 'transient-activation', isBlessed=%d, "
"hasValidTransientActivation=%d",
isElementBlessed, hasTransientActivation);
return isElementBlessed || hasTransientActivation;
}
// On GeckoView, we don't store any site's permission in permission manager, we
// would check the GV request status to know if the site can be allowed to play.
// But on other platforms, we would store the site's permission in permission
// manager.
#if defined(MOZ_WIDGET_ANDROID)
using RType = GVAutoplayRequestType;
static bool IsGVAutoplayRequestAllowed(nsPIDOMWindowInner* aWindow,
RType aType) {
if (!aWindow) {
return false;
}
RefPtr<BrowsingContext> context = aWindow->GetBrowsingContext()->Top();
GVAutoplayRequestStatus status =
aType == RType::eAUDIBLE ? context->GetGVAudibleAutoplayRequestStatus()
: context->GetGVInaudibleAutoplayRequestStatus();
return status == GVAutoplayRequestStatus::eALLOWED;
}
static bool IsGVAutoplayRequestAllowed(
const HTMLMediaElement& aElement,
RType aType) {
// On GV, blocking model is the first thing we would check inside Gecko, and
// if the media is not allowed by that, then we would check the response from
// the embedding app to decide the final result.
if (IsAllowedToPlayByBlockingModel(aElement)) {
return true;
}
RefPtr<nsPIDOMWindowInner> window = aElement.OwnerDoc()->GetInnerWindow();
if (!window) {
return false;
}
return IsGVAutoplayRequestAllowed(window, aType);
}
#endif
static bool IsAllowedToPlayInternal(
const HTMLMediaElement& aElement) {
#if defined(MOZ_WIDGET_ANDROID)
if (StaticPrefs::media_geckoview_autoplay_request()) {
return IsGVAutoplayRequestAllowed(
aElement, IsMediaElementInaudible(aElement) ? RType::eINAUDIBLE
: RType::eAUDIBLE);
}
#endif
bool isInaudible = IsMediaElementInaudible(aElement);
bool isUsingAutoplayModel = IsAllowedToPlayByBlockingModel(aElement);
uint32_t defaultBehaviour = DefaultAutoplayBehaviour();
uint32_t sitePermission =
SiteAutoplayPerm(aElement.OwnerDoc()->GetInnerWindow());
AUTOPLAY_LOG(
"IsAllowedToPlayInternal, isInaudible=%d,"
"isUsingAutoplayModel=%d, sitePermission=%d, defaultBehaviour=%d",
isInaudible, isUsingAutoplayModel, sitePermission, defaultBehaviour);
// For site permissions we store permissionManager values except
// for BLOCKED_ALL, for the default pref values we store
// nsIAutoplay values.
if (sitePermission == nsIPermissionManager::ALLOW_ACTION) {
return true;
}
if (sitePermission == nsIPermissionManager::DENY_ACTION) {
return isInaudible || isUsingAutoplayModel;
}
if (sitePermission == nsIAutoplay::BLOCKED_ALL) {
return isUsingAutoplayModel;
}
if (defaultBehaviour == nsIAutoplay::ALLOWED) {
return true;
}
if (defaultBehaviour == nsIAutoplay::BLOCKED) {
return isInaudible || isUsingAutoplayModel;
}
MOZ_ASSERT(defaultBehaviour == nsIAutoplay::BLOCKED_ALL);
return isUsingAutoplayModel;
}
/* static */
bool AutoplayPolicy::IsAllowedToPlay(
const HTMLMediaElement& aElement) {
const bool result = IsAllowedToPlayInternal(aElement);
AUTOPLAY_LOG(
"IsAllowedToPlay, mediaElement=%p, isAllowToPlay=%s", &aElement,
result ?
"allowed" :
"blocked");
return result;
}
/* static */
bool AutoplayPolicy::IsAllowedToPlay(
const AudioContext& aContext) {
/**
* The autoplay checking has 5 different phases,
* 1. check whether audio context itself meets the autoplay condition
* 2. check if we enable blocking web audio or not
* (only support blocking when using user-gesture-activation model)
* 3. check whether the site is in the autoplay whitelist
* 4. check global autoplay setting and check wether the site is in the
* autoplay blacklist.
* 5. check whether media is allowed under current blocking model
* (only support user-gesture-activation model)
*/
if (aContext.IsOffline()) {
return true;
}
if (!IsEnableBlockingWebAudioByUserGesturePolicy()) {
return true;
}
nsPIDOMWindowInner* window = aContext.GetOwnerWindow();
uint32_t sitePermission = SiteAutoplayPerm(window);
if (sitePermission == nsIPermissionManager::ALLOW_ACTION) {
AUTOPLAY_LOG(
"Allow autoplay as document has permanent autoplay permission.");
return true;
}
if (DefaultAutoplayBehaviour() == nsIAutoplay::ALLOWED &&
sitePermission != nsIPermissionManager::DENY_ACTION &&
sitePermission != nsIAutoplay::BLOCKED_ALL) {
AUTOPLAY_LOG(
"Allow autoplay as global autoplay setting is allowing autoplay by "
"default.");
return true;
}
return IsWindowAllowedToPlayOverall(window);
}
enum class DocumentAutoplayPolicy : uint8_t {
Allowed,
Allowed_muted,
Disallowed
};
/* static */
DocumentAutoplayPolicy IsDocAllowedToPlay(
const Document& aDocument) {
RefPtr<nsPIDOMWindowInner> window = aDocument.GetInnerWindow();
#if defined(MOZ_WIDGET_ANDROID)
if (StaticPrefs::media_geckoview_autoplay_request()) {
const bool isWindowAllowedToPlay = IsWindowAllowedToPlayOverall(window);
if (IsGVAutoplayRequestAllowed(window, RType::eAUDIBLE)) {
return DocumentAutoplayPolicy::Allowed;
}
if (IsGVAutoplayRequestAllowed(window, RType::eINAUDIBLE)) {
return isWindowAllowedToPlay ? DocumentAutoplayPolicy::Allowed
: DocumentAutoplayPolicy::Allowed_muted;
}
return isWindowAllowedToPlay ? DocumentAutoplayPolicy::Allowed
: DocumentAutoplayPolicy::Disallowed;
}
#endif
const uint32_t sitePermission = SiteAutoplayPerm(window);
const uint32_t globalPermission = DefaultAutoplayBehaviour();
const uint32_t policy = StaticPrefs::media_autoplay_blocking_policy();
const bool isWindowAllowedToPlayByGesture =
policy != sPOLICY_USER_INPUT_DEPTH &&
IsWindowAllowedToPlayByUserGesture(window);
const bool isWindowAllowedToPlayByTraits =
IsWindowAllowedToPlayByTraits(window);
AUTOPLAY_LOG(
"IsDocAllowedToPlay(), policy=%d, sitePermission=%d, "
"globalPermission=%d, isWindowAllowedToPlayByGesture=%d, "
"isWindowAllowedToPlayByTraits=%d",
policy, sitePermission, globalPermission, isWindowAllowedToPlayByGesture,
isWindowAllowedToPlayByTraits);
if ((globalPermission == nsIAutoplay::ALLOWED &&
(sitePermission != nsIPermissionManager::DENY_ACTION &&
sitePermission != nsIAutoplay::BLOCKED_ALL)) ||
sitePermission == nsIPermissionManager::ALLOW_ACTION ||
isWindowAllowedToPlayByGesture || isWindowAllowedToPlayByTraits) {
return DocumentAutoplayPolicy::Allowed;
}
if ((globalPermission == nsIAutoplay::BLOCKED &&
sitePermission != nsIAutoplay::BLOCKED_ALL) ||
sitePermission == nsIPermissionManager::DENY_ACTION) {
return DocumentAutoplayPolicy::Allowed_muted;
}
return DocumentAutoplayPolicy::Disallowed;
}
/* static */
uint32_t AutoplayPolicy::GetSiteAutoplayPermission(nsIPrincipal* aPrincipal) {
if (!aPrincipal) {
return nsIPermissionManager::DENY_ACTION;
}
nsCOMPtr<nsIPermissionManager> permMgr =
components::PermissionManager::Service();
if (!permMgr) {
return nsIPermissionManager::DENY_ACTION;
}
uint32_t perm = nsIPermissionManager::DENY_ACTION;
permMgr->TestExactPermissionFromPrincipal(aPrincipal,
"autoplay-media"_ns,
&perm);
return perm;
}
/* static */
dom::AutoplayPolicy AutoplayPolicy::GetAutoplayPolicy(
const dom::HTMLMediaElement& aElement) {
// Note, the site permission can contain following values :
// - UNKNOWN_ACTION : no permission set for this site
// - ALLOW_ACTION : allowed to autoplay
// - DENY_ACTION : allowed inaudible autoplay, disallowed inaudible autoplay
// - nsIAutoplay::BLOCKED_ALL : autoplay disallowed
// and the global permissions would be nsIAutoplay::{BLOCKED, ALLOWED,
// BLOCKED_ALL}
const uint32_t sitePermission =
SiteAutoplayPerm(aElement.OwnerDoc()->GetInnerWindow());
const uint32_t globalPermission = DefaultAutoplayBehaviour();
const bool isAllowedToPlayByBlockingModel =
IsAllowedToPlayByBlockingModel(aElement);
AUTOPLAY_LOG(
"IsAllowedToPlay(element), sitePermission=%d, globalPermission=%d, "
"isAllowedToPlayByBlockingModel=%d",
sitePermission, globalPermission, isAllowedToPlayByBlockingModel);
#if defined(MOZ_WIDGET_ANDROID)
if (StaticPrefs::media_geckoview_autoplay_request()) {
if (IsGVAutoplayRequestAllowed(aElement, RType::eAUDIBLE)) {
return dom::AutoplayPolicy::Allowed;
}
else if (IsGVAutoplayRequestAllowed(aElement, RType::eINAUDIBLE)) {
return isAllowedToPlayByBlockingModel
? dom::AutoplayPolicy::Allowed
: dom::AutoplayPolicy::Allowed_muted;
}
else {
return isAllowedToPlayByBlockingModel ? dom::AutoplayPolicy::Allowed
: dom::AutoplayPolicy::Disallowed;
}
}
#endif
// These are situations when an element is allowed to autoplay
// 1. The site permission is explicitly allowed
// 2. The global permission is allowed, and the site isn't explicitly
// disallowed
// 3. The blocking model is explicitly allowed this element
if (sitePermission == nsIPermissionManager::ALLOW_ACTION ||
(globalPermission == nsIAutoplay::ALLOWED &&
(sitePermission != nsIPermissionManager::DENY_ACTION &&
sitePermission != nsIAutoplay::BLOCKED_ALL)) ||
isAllowedToPlayByBlockingModel) {
return dom::AutoplayPolicy::Allowed;
}
// These are situations when a element is allowed to autoplay only when it's
// inaudible.
// 1. The site permission is block-audible-autoplay
// 2. The global permission is block-audible-autoplay, and the site permission
// isn't block-all-autoplay
if (sitePermission == nsIPermissionManager::DENY_ACTION ||
(globalPermission == nsIAutoplay::BLOCKED &&
sitePermission != nsIAutoplay::BLOCKED_ALL)) {
return dom::AutoplayPolicy::Allowed_muted;
}
return dom::AutoplayPolicy::Disallowed;
}
/* static */
dom::AutoplayPolicy AutoplayPolicy::GetAutoplayPolicy(
const dom::AudioContext& aContext) {
if (AutoplayPolicy::IsAllowedToPlay(aContext)) {
return dom::AutoplayPolicy::Allowed;
}
return dom::AutoplayPolicy::Disallowed;
}
/* static */
dom::AutoplayPolicy AutoplayPolicy::GetAutoplayPolicy(
const dom::AutoplayPolicyMediaType& aType,
const dom::Document& aDoc) {
DocumentAutoplayPolicy policy = IsDocAllowedToPlay(aDoc);
// https://w3c.github.io/autoplay/#query-by-a-media-type
if (aType == dom::AutoplayPolicyMediaType::Audiocontext) {
return policy == DocumentAutoplayPolicy::Allowed
? dom::AutoplayPolicy::Allowed
: dom::AutoplayPolicy::Disallowed;
}
MOZ_ASSERT(aType == dom::AutoplayPolicyMediaType::Mediaelement);
if (policy == DocumentAutoplayPolicy::Allowed) {
return dom::AutoplayPolicy::Allowed;
}
if (policy == DocumentAutoplayPolicy::Allowed_muted) {
return dom::AutoplayPolicy::Allowed_muted;
}
return dom::AutoplayPolicy::Disallowed;
}
}
// namespace mozilla::media
