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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/dom/TrustedTypePolicyFactory.h"
#include <utility>
#include "nsLiteralString.h"
#include "mozilla/AlreadyAddRefed.h"
#include "mozilla/ErrorResult.h"
#include "mozilla/RefPtr.h"
#include "mozilla/dom/CSPViolationData.h"
#include "mozilla/dom/TrustedTypePolicy.h"
#include "mozilla/dom/TrustedTypeUtils.h"
#include "mozilla/dom/nsCSPUtils.h"
using namespace mozilla::dom::TrustedTypeUtils;
namespace mozilla::dom {
NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(TrustedTypePolicyFactory, mGlobalObject,
mDefaultPolicy)
TrustedTypePolicyFactory::TrustedTypePolicyFactory(
nsIGlobalObject* aGlobalObject)
: mGlobalObject{aGlobalObject} {}
JSObject* TrustedTypePolicyFactory::WrapObject(
JSContext* aCx, JS::Handle<JSObject*> aGivenProto) {
return TrustedTypePolicyFactory_Binding::Wrap(aCx, this, aGivenProto);
}
constexpr size_t kCreatePolicyCSPViolationMaxSampleLength = 40;
static CSPViolationData CreateCSPViolationData(JSContext* aJSContext,
uint32_t aPolicyIndex,
const nsAString& aPolicyName) {
auto caller = JSCallingLocation::Get(aJSContext);
const nsAString& sample =
Substring(aPolicyName, /* aStartPos */ 0,
/* aLength */ kCreatePolicyCSPViolationMaxSampleLength);
return {aPolicyIndex,
CSPViolationData::Resource{
CSPViolationData::BlockedContentSource::TrustedTypesPolicy},
nsIContentSecurityPolicy::TRUSTED_TYPES_DIRECTIVE,
caller.FileName(),
caller.mLine,
caller.mColumn,
/* aElement */ nullptr,
sample};
}
// Default implementation in the .cpp file required because `mDefaultPolicy`
// requires a definition for `TrustedTypePolicy`.
TrustedTypePolicyFactory::~TrustedTypePolicyFactory() = default;
auto TrustedTypePolicyFactory::ShouldTrustedTypePolicyCreationBeBlockedByCSP(
JSContext* aJSContext,
const nsAString& aPolicyName) const -> PolicyCreation {
// CSP-support for Workers will be added in
// That is, currently only Windows are supported.
nsIContentSecurityPolicy* csp =
mGlobalObject->GetAsInnerWindow()
? mGlobalObject->GetAsInnerWindow()->GetCsp()
: nullptr;
auto result = PolicyCreation::Allowed;
if (csp) {
uint32_t numPolicies = 0;
csp->GetPolicyCount(&numPolicies);
for (uint64_t i = 0; i < numPolicies; ++i) {
const nsCSPPolicy* policy = csp->GetPolicy(i);
if (policy->hasDirective(
nsIContentSecurityPolicy::TRUSTED_TYPES_DIRECTIVE)) {
if (policy->ShouldCreateViolationForNewTrustedTypesPolicy(
aPolicyName, mCreatedPolicyNames)) {
// Only required for Workers;
nsICSPEventListener* cspEventListener{nullptr};
CSPViolationData cspViolationData{
CreateCSPViolationData(aJSContext, i, aPolicyName)};
csp->LogTrustedTypesViolationDetailsUnchecked(
std::move(cspViolationData),
NS_LITERAL_STRING_FROM_CSTRING(
TRUSTED_TYPES_VIOLATION_OBSERVER_TOPIC),
cspEventListener);
if (policy->getDisposition() == nsCSPPolicy::Disposition::Enforce) {
result = PolicyCreation::Blocked;
}
}
}
}
}
return result;
}
constexpr nsLiteralString kDefaultPolicyName = u"default"_ns;
already_AddRefed<TrustedTypePolicy> TrustedTypePolicyFactory::CreatePolicy(
JSContext* aJSContext, const nsAString& aPolicyName,
const TrustedTypePolicyOptions& aPolicyOptions, ErrorResult& aRv) {
if (PolicyCreation::Blocked ==
ShouldTrustedTypePolicyCreationBeBlockedByCSP(aJSContext, aPolicyName)) {
nsCString errorMessage =
"Content-Security-Policy blocked creating policy named '"_ns +
NS_ConvertUTF16toUTF8(aPolicyName) + "'"_ns;
// TODO: perhaps throw different TypeError messages,
aRv.ThrowTypeError(errorMessage);
return nullptr;
}
if (aPolicyName.Equals(kDefaultPolicyName) && mDefaultPolicy) {
aRv.ThrowTypeError("Tried to create a second default policy"_ns);
return nullptr;
}
TrustedTypePolicy::Options options;
if (aPolicyOptions.mCreateHTML.WasPassed()) {
options.mCreateHTMLCallback = &aPolicyOptions.mCreateHTML.Value();
}
if (aPolicyOptions.mCreateScript.WasPassed()) {
options.mCreateScriptCallback = &aPolicyOptions.mCreateScript.Value();
}
if (aPolicyOptions.mCreateScriptURL.WasPassed()) {
options.mCreateScriptURLCallback = &aPolicyOptions.mCreateScriptURL.Value();
}
RefPtr<TrustedTypePolicy> policy =
MakeRefPtr<TrustedTypePolicy>(this, aPolicyName, std::move(options));
if (aPolicyName.Equals(kDefaultPolicyName)) {
mDefaultPolicy = policy;
}
mCreatedPolicyNames.AppendElement(aPolicyName);
return policy.forget();
}
#define IS_TRUSTED_TYPE_IMPL(_trustedTypeSuffix) \
bool TrustedTypePolicyFactory::Is##_trustedTypeSuffix( \
JSContext*, const JS::Handle<JS::Value>& aValue) const { \
/** \
* No need to check the internal slot. \
* Ensured by the corresponding test: \
*/ \
return aValue.isObject() && \
IS_INSTANCE_OF(Trusted##_trustedTypeSuffix, &aValue.toObject()); \
}
IS_TRUSTED_TYPE_IMPL(HTML);
IS_TRUSTED_TYPE_IMPL(Script);
IS_TRUSTED_TYPE_IMPL(ScriptURL);
already_AddRefed<TrustedHTML> TrustedTypePolicyFactory::EmptyHTML() {
// Preserving the wrapper ensures:
// ```
// const e = trustedTypes.emptyHTML;
// e === trustedTypes.emptyHTML;
// ```
// which comes with the cost of keeping the factory, one per global, alive.
// An additional benefit is it saves the cost of re-instantiating potentially
// multiple emptyHML objects. Both, the JS- and the C++-objects.
dom::PreserveWrapper(this);
RefPtr<TrustedHTML> result = new TrustedHTML(EmptyString());
return result.forget();
}
already_AddRefed<TrustedScript> TrustedTypePolicyFactory::EmptyScript() {
// See the explanation in `EmptyHTML()`.
dom::PreserveWrapper(this);
RefPtr<TrustedScript> result = new TrustedScript(EmptyString());
return result.forget();
}
// TODO(fwang): Improve this API:
// - Rename aTagName parameter to use aLocalName instead
// - Remove ASCII-case-insensitivity for aTagName and aAttribute
// - Make aElementNs default to HTML namespace, so special handling for an empty
void TrustedTypePolicyFactory::GetAttributeType(const nsAString& aTagName,
const nsAString& aAttribute,
const nsAString& aElementNs,
const nsAString& aAttrNs,
DOMString& aResult) {
// We first determine the namespace IDs for the element and attribute.
// Currently, GetTrustedTypeDataForAttribute() only test a few of them so use
// direct string comparisons instead of relying on
// nsNameSpaceManager::GetNameSpaceID().
// GetTrustedTypeDataForAttribute() can only return true for empty or XLink
// attribute namespaces, so don't bother calling it for other namespaces.
int32_t attributeNamespaceID = kNameSpaceID_Unknown;
if (aAttrNs.IsEmpty()) {
attributeNamespaceID = kNameSpaceID_None;
} else if (nsGkAtoms::nsuri_xlink->Equals(aAttrNs)) {
attributeNamespaceID = kNameSpaceID_XLink;
} else {
aResult.SetNull();
return;
}
// GetTrustedTypeDataForAttribute() only test HTML or SVG element namespaces,
// for testing event handler attributes the element namespace does not matter.
int32_t elementNamespaceID = kNameSpaceID_Unknown;
if (aElementNs.IsEmpty() || nsGkAtoms::nsuri_xhtml->Equals(aElementNs)) {
elementNamespaceID = kNameSpaceID_XHTML;
} else if (nsGkAtoms::nsuri_svg->Equals(aElementNs)) {
elementNamespaceID = kNameSpaceID_SVG;
}
nsAutoString attribute;
nsContentUtils::ASCIIToLower(aAttribute, attribute);
RefPtr<nsAtom> attributeAtom = NS_Atomize(attribute);
nsAutoString localName;
nsContentUtils::ASCIIToLower(aTagName, localName);
RefPtr<nsAtom> elementAtom = NS_Atomize(localName);
TrustedType trustedType;
nsAutoString unusedSink;
if (GetTrustedTypeDataForAttribute(elementAtom, elementNamespaceID,
attributeAtom, attributeNamespaceID,
trustedType, unusedSink)) {
aResult.SetKnownLiveString(GetTrustedTypeName(trustedType));
return;
}
aResult.SetNull();
}
// TODO(fwang): Improve this API:
// - Rename aTagName parameter to use aLocalName instead
// - Remove ASCII-case-insensitivity for aTagName
// - Make aElementNs default to HTML namespace, so special handling for an empty
void TrustedTypePolicyFactory::GetPropertyType(const nsAString& aTagName,
const nsAString& aProperty,
const nsAString& aElementNs,
DOMString& aResult) {
RefPtr<nsAtom> propertyAtom = NS_Atomize(aProperty);
if (aElementNs.IsEmpty() || nsGkAtoms::nsuri_xhtml->Equals(aElementNs)) {
if (nsContentUtils::EqualsIgnoreASCIICase(
aTagName, nsDependentAtomString(nsGkAtoms::iframe))) {
// HTMLIFrameElement
if (propertyAtom == nsGkAtoms::srcdoc) {
aResult.SetKnownLiveString(GetTrustedTypeName<TrustedHTML>());
return;
}
} else if (nsContentUtils::EqualsIgnoreASCIICase(
aTagName, nsDependentAtomString(nsGkAtoms::script))) {
// HTMLScriptElement
if (propertyAtom == nsGkAtoms::innerText ||
propertyAtom == nsGkAtoms::text ||
propertyAtom == nsGkAtoms::textContent) {
aResult.SetKnownLiveString(GetTrustedTypeName<TrustedScript>());
return;
}
if (propertyAtom == nsGkAtoms::src) {
aResult.SetKnownLiveString(GetTrustedTypeName<TrustedScriptURL>());
return;
}
}
}
// *
if (propertyAtom == nsGkAtoms::innerHTML ||
propertyAtom == nsGkAtoms::outerHTML) {
aResult.SetKnownLiveString(GetTrustedTypeName<TrustedHTML>());
return;
}
aResult.SetNull();
}
} // namespace mozilla::dom