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/* -*- 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 "mozilla/AsyncEventDispatcher.h"
#include "mozilla/dom/BindContext.h"
#include "mozilla/dom/HTMLMetaElement.h"
#include "mozilla/dom/HTMLMetaElementBinding.h"
#include "mozilla/dom/nsCSPService.h"
#include "mozilla/dom/nsCSPUtils.h"
#include "mozilla/dom/ViewportMetaData.h"
#include "mozilla/Logging.h"
#include "mozilla/StaticPrefs_security.h"
#include "nsContentUtils.h"
#include "nsSandboxFlags.h"
#include "nsStyleConsts.h"
#include "nsIXMLContentSink.h"
static mozilla::LazyLogModule gMetaElementLog("nsMetaElement");
#define LOG(msg) MOZ_LOG(gMetaElementLog, mozilla::LogLevel::Debug, msg)
#define LOG_ENABLED() MOZ_LOG_TEST(gMetaElementLog, mozilla::LogLevel::Debug)
NS_IMPL_NS_NEW_HTML_ELEMENT(Meta)
namespace mozilla {
namespace dom {
HTMLMetaElement::HTMLMetaElement(
already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo)
: nsGenericHTMLElement(std::move(aNodeInfo)) {}
HTMLMetaElement::~HTMLMetaElement() = default;
NS_IMPL_ELEMENT_CLONE(HTMLMetaElement)
void HTMLMetaElement::SetMetaReferrer(Document* aDocument) {
if (!aDocument || !AttrValueIs(kNameSpaceID_None, nsGkAtoms::name,
nsGkAtoms::referrer, eIgnoreCase)) {
return;
}
nsAutoString content;
GetContent(content);
Element* headElt = aDocument->GetHeadElement();
if (headElt && IsInclusiveDescendantOf(headElt)) {
content = nsContentUtils::TrimWhitespace<nsContentUtils::IsHTMLWhitespace>(
content);
aDocument->UpdateReferrerInfoFromMeta(content, false);
}
}
nsresult HTMLMetaElement::AfterSetAttr(int32_t aNameSpaceID, nsAtom* aName,
const nsAttrValue* aValue,
const nsAttrValue* aOldValue,
nsIPrincipal* aSubjectPrincipal,
bool aNotify) {
if (aNameSpaceID == kNameSpaceID_None) {
Document* document = GetUncomposedDoc();
if (aName == nsGkAtoms::content) {
if (document && AttrValueIs(kNameSpaceID_None, nsGkAtoms::name,
nsGkAtoms::viewport, eIgnoreCase)) {
ProcessViewportContent(document);
}
CreateAndDispatchEvent(document, u"DOMMetaChanged"_ns);
} else if (document && aName == nsGkAtoms::name) {
if (aValue && aValue->Equals(nsGkAtoms::viewport, eIgnoreCase)) {
ProcessViewportContent(document);
} else if (aOldValue &&
aOldValue->Equals(nsGkAtoms::viewport, eIgnoreCase)) {
DiscardViewportContent(document);
}
CreateAndDispatchEvent(document, u"DOMMetaChanged"_ns);
}
// Update referrer policy when it got changed from JS
SetMetaReferrer(document);
}
return nsGenericHTMLElement::AfterSetAttr(
aNameSpaceID, aName, aValue, aOldValue, aSubjectPrincipal, aNotify);
}
nsresult HTMLMetaElement::BindToTree(BindContext& aContext, nsINode& aParent) {
nsresult rv = nsGenericHTMLElement::BindToTree(aContext, aParent);
NS_ENSURE_SUCCESS(rv, rv);
if (!IsInUncomposedDoc()) {
return rv;
}
Document& doc = aContext.OwnerDoc();
bool shouldProcessMeta = true;
// We don't want to call ProcessMETATag when we are pretty print
// the document
if (doc.IsXMLDocument()) {
if (nsCOMPtr<nsIXMLContentSink> xmlSink =
do_QueryInterface(doc.GetCurrentContentSink())) {
if (xmlSink->IsPrettyPrintXML() &&
xmlSink->IsPrettyPrintHasSpecialRoot()) {
shouldProcessMeta = false;
}
}
}
if (shouldProcessMeta) {
doc.ProcessMETATag(this);
}
if (AttrValueIs(kNameSpaceID_None, nsGkAtoms::name, nsGkAtoms::viewport,
eIgnoreCase)) {
ProcessViewportContent(&doc);
}
if (AttrValueIs(kNameSpaceID_None, nsGkAtoms::httpEquiv, nsGkAtoms::headerCSP,
eIgnoreCase)) {
// only accept <meta http-equiv="Content-Security-Policy" content=""> if it
// appears in the <head> element.
Element* headElt = doc.GetHeadElement();
if (headElt && IsInclusiveDescendantOf(headElt)) {
nsAutoString content;
GetContent(content);
if (LOG_ENABLED()) {
nsAutoCString documentURIspec;
if (nsIURI* documentURI = doc.GetDocumentURI()) {
documentURI->GetAsciiSpec(documentURIspec);
}
LOG(
("HTMLMetaElement %p sets CSP '%s' on document=%p, "
"document-uri=%s",
this, NS_ConvertUTF16toUTF8(content).get(), &doc,
documentURIspec.get()));
}
CSP_ApplyMetaCSPToDoc(doc, content);
}
}
// Referrer Policy spec requires a <meta name="referrer" tag to be in the
// <head> element.
SetMetaReferrer(&doc);
CreateAndDispatchEvent(&doc, u"DOMMetaAdded"_ns);
return rv;
}
void HTMLMetaElement::UnbindFromTree(bool aNullParent) {
nsCOMPtr<Document> oldDoc = GetUncomposedDoc();
if (oldDoc && AttrValueIs(kNameSpaceID_None, nsGkAtoms::name,
nsGkAtoms::viewport, eIgnoreCase)) {
DiscardViewportContent(oldDoc);
}
CreateAndDispatchEvent(oldDoc, u"DOMMetaRemoved"_ns);
nsGenericHTMLElement::UnbindFromTree(aNullParent);
}
void HTMLMetaElement::CreateAndDispatchEvent(Document* aDoc,
const nsAString& aEventName) {
if (!aDoc) return;
RefPtr<AsyncEventDispatcher> asyncDispatcher = new AsyncEventDispatcher(
this, aEventName, CanBubble::eYes, ChromeOnlyDispatch::eYes);
asyncDispatcher->RunDOMEventWhenSafe();
}
JSObject* HTMLMetaElement::WrapNode(JSContext* aCx,
JS::Handle<JSObject*> aGivenProto) {
return HTMLMetaElement_Binding::Wrap(aCx, this, aGivenProto);
}
void HTMLMetaElement::ProcessViewportContent(Document* aDocument) {
if (!HasAttr(kNameSpaceID_None, nsGkAtoms::content)) {
// Call Document::RemoveMetaViewportElement for cases that the content
// attribute is removed.
// NOTE: RemoveMetaViewportElement enumerates all existing meta viewport
// tags in the case where this element hasn't been there, i.e. this element
// is newly added to the document, but it should be fine because a document
// unlikely has a bunch of meta viewport tags.
aDocument->RemoveMetaViewportElement(this);
return;
}
nsAutoString content;
GetContent(content);
aDocument->SetHeaderData(nsGkAtoms::viewport, content);
ViewportMetaData data(content);
aDocument->AddMetaViewportElement(this, std::move(data));
}
void HTMLMetaElement::DiscardViewportContent(Document* aDocument) {
aDocument->RemoveMetaViewportElement(this);
}
} // namespace dom
} // namespace mozilla