From 6bf0a5cb5034a7e684dcc3500e841785237ce2dd Mon Sep 17 00:00:00 2001
From: Daniel Baumann <daniel.baumann@progress-linux.org>
Date: Sun, 7 Apr 2024 19:32:43 +0200
Subject: Adding upstream version 1:115.7.0.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
---
 dom/security/featurepolicy/Feature.cpp             |  76 ++++
 dom/security/featurepolicy/Feature.h               |  65 ++++
 dom/security/featurepolicy/FeaturePolicy.cpp       | 334 ++++++++++++++++
 dom/security/featurepolicy/FeaturePolicy.h         | 204 ++++++++++
 dom/security/featurepolicy/FeaturePolicyParser.cpp | 157 ++++++++
 dom/security/featurepolicy/FeaturePolicyParser.h   |  30 ++
 dom/security/featurepolicy/FeaturePolicyUtils.cpp  | 309 +++++++++++++++
 dom/security/featurepolicy/FeaturePolicyUtils.h    |  91 +++++
 dom/security/featurepolicy/fuzztest/fp_fuzzer.cpp  |  67 ++++
 dom/security/featurepolicy/fuzztest/fp_fuzzer.dict |  54 +++
 dom/security/featurepolicy/fuzztest/moz.build      |  18 +
 dom/security/featurepolicy/moz.build               |  36 ++
 .../test/gtest/TestFeaturePolicyParser.cpp         | 162 ++++++++
 dom/security/featurepolicy/test/gtest/moz.build    |  13 +
 .../featurepolicy/test/mochitest/empty.html        |   1 +
 .../featurepolicy/test/mochitest/mochitest.ini     |  11 +
 .../test/mochitest/test_featureList.html           |  44 +++
 .../featurepolicy/test/mochitest/test_parser.html  | 418 +++++++++++++++++++++
 .../test/mochitest/test_parser.html^headers^       |   1 +
 19 files changed, 2091 insertions(+)
 create mode 100644 dom/security/featurepolicy/Feature.cpp
 create mode 100644 dom/security/featurepolicy/Feature.h
 create mode 100644 dom/security/featurepolicy/FeaturePolicy.cpp
 create mode 100644 dom/security/featurepolicy/FeaturePolicy.h
 create mode 100644 dom/security/featurepolicy/FeaturePolicyParser.cpp
 create mode 100644 dom/security/featurepolicy/FeaturePolicyParser.h
 create mode 100644 dom/security/featurepolicy/FeaturePolicyUtils.cpp
 create mode 100644 dom/security/featurepolicy/FeaturePolicyUtils.h
 create mode 100644 dom/security/featurepolicy/fuzztest/fp_fuzzer.cpp
 create mode 100644 dom/security/featurepolicy/fuzztest/fp_fuzzer.dict
 create mode 100644 dom/security/featurepolicy/fuzztest/moz.build
 create mode 100644 dom/security/featurepolicy/moz.build
 create mode 100644 dom/security/featurepolicy/test/gtest/TestFeaturePolicyParser.cpp
 create mode 100644 dom/security/featurepolicy/test/gtest/moz.build
 create mode 100644 dom/security/featurepolicy/test/mochitest/empty.html
 create mode 100644 dom/security/featurepolicy/test/mochitest/mochitest.ini
 create mode 100644 dom/security/featurepolicy/test/mochitest/test_featureList.html
 create mode 100644 dom/security/featurepolicy/test/mochitest/test_parser.html
 create mode 100644 dom/security/featurepolicy/test/mochitest/test_parser.html^headers^

(limited to 'dom/security/featurepolicy')

diff --git a/dom/security/featurepolicy/Feature.cpp b/dom/security/featurepolicy/Feature.cpp
new file mode 100644
index 0000000000..92a92369da
--- /dev/null
+++ b/dom/security/featurepolicy/Feature.cpp
@@ -0,0 +1,76 @@
+/* -*- 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 "Feature.h"
+#include "mozilla/BasePrincipal.h"
+
+namespace mozilla::dom {
+
+void Feature::GetAllowList(nsTArray<nsCOMPtr<nsIPrincipal>>& aList) const {
+  MOZ_ASSERT(mPolicy == eAllowList);
+  aList.AppendElements(mAllowList);
+}
+
+bool Feature::Allows(nsIPrincipal* aPrincipal) const {
+  if (mPolicy == eNone) {
+    return false;
+  }
+
+  if (mPolicy == eAll) {
+    return true;
+  }
+
+  return AllowListContains(aPrincipal);
+}
+
+Feature::Feature(const nsAString& aFeatureName)
+    : mFeatureName(aFeatureName), mPolicy(eAllowList) {}
+
+Feature::~Feature() = default;
+
+const nsAString& Feature::Name() const { return mFeatureName; }
+
+void Feature::SetAllowsNone() {
+  mPolicy = eNone;
+  mAllowList.Clear();
+}
+
+bool Feature::AllowsNone() const { return mPolicy == eNone; }
+
+void Feature::SetAllowsAll() {
+  mPolicy = eAll;
+  mAllowList.Clear();
+}
+
+bool Feature::AllowsAll() const { return mPolicy == eAll; }
+
+void Feature::AppendToAllowList(nsIPrincipal* aPrincipal) {
+  MOZ_ASSERT(aPrincipal);
+
+  mPolicy = eAllowList;
+  mAllowList.AppendElement(aPrincipal);
+}
+
+bool Feature::AllowListContains(nsIPrincipal* aPrincipal) const {
+  MOZ_ASSERT(aPrincipal);
+
+  if (!HasAllowList()) {
+    return false;
+  }
+
+  for (nsIPrincipal* principal : mAllowList) {
+    if (BasePrincipal::Cast(principal)->Subsumes(
+            aPrincipal, BasePrincipal::ConsiderDocumentDomain)) {
+      return true;
+    }
+  }
+
+  return false;
+}
+
+bool Feature::HasAllowList() const { return mPolicy == eAllowList; }
+
+}  // namespace mozilla::dom
diff --git a/dom/security/featurepolicy/Feature.h b/dom/security/featurepolicy/Feature.h
new file mode 100644
index 0000000000..e8a3d89c81
--- /dev/null
+++ b/dom/security/featurepolicy/Feature.h
@@ -0,0 +1,65 @@
+/* -*- 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/. */
+
+#ifndef mozilla_dom_Feature_h
+#define mozilla_dom_Feature_h
+
+#include "nsString.h"
+#include "nsTArray.h"
+#include "nsCOMPtr.h"
+
+class nsIPrincipal;
+
+namespace mozilla::dom {
+
+class Feature final {
+ public:
+  explicit Feature(const nsAString& aFeatureName);
+
+  ~Feature();
+
+  const nsAString& Name() const;
+
+  void SetAllowsNone();
+
+  bool AllowsNone() const;
+
+  void SetAllowsAll();
+
+  bool AllowsAll() const;
+
+  void AppendToAllowList(nsIPrincipal* aPrincipal);
+
+  void GetAllowList(nsTArray<nsCOMPtr<nsIPrincipal>>& aList) const;
+
+  bool AllowListContains(nsIPrincipal* aPrincipal) const;
+
+  bool HasAllowList() const;
+
+  bool Allows(nsIPrincipal* aPrincipal) const;
+
+ private:
+  nsString mFeatureName;
+
+  enum Policy {
+    // denotes a policy of "feature 'none'"
+    eNone,
+
+    // denotes a policy of "feature *"
+    eAll,
+
+    // denotes a policy of "feature bar.com foo.com"
+    eAllowList,
+  };
+
+  Policy mPolicy;
+
+  CopyableTArray<nsCOMPtr<nsIPrincipal>> mAllowList;
+};
+
+}  // namespace mozilla::dom
+
+#endif  // mozilla_dom_Feature_h
diff --git a/dom/security/featurepolicy/FeaturePolicy.cpp b/dom/security/featurepolicy/FeaturePolicy.cpp
new file mode 100644
index 0000000000..cb5c1ea44a
--- /dev/null
+++ b/dom/security/featurepolicy/FeaturePolicy.cpp
@@ -0,0 +1,334 @@
+/* -*- 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 "FeaturePolicy.h"
+#include "mozilla/BasePrincipal.h"
+#include "mozilla/dom/Feature.h"
+#include "mozilla/dom/FeaturePolicyBinding.h"
+#include "mozilla/dom/FeaturePolicyParser.h"
+#include "mozilla/dom/FeaturePolicyUtils.h"
+#include "mozilla/StaticPrefs_dom.h"
+#include "nsContentUtils.h"
+#include "nsNetUtil.h"
+
+namespace mozilla::dom {
+
+NS_IMPL_CYCLE_COLLECTION_WRAPPERCACHE(FeaturePolicy)
+NS_IMPL_CYCLE_COLLECTING_ADDREF(FeaturePolicy)
+NS_IMPL_CYCLE_COLLECTING_RELEASE(FeaturePolicy)
+
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(FeaturePolicy)
+  NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
+  NS_INTERFACE_MAP_ENTRY(nsISupports)
+NS_INTERFACE_MAP_END
+
+FeaturePolicy::FeaturePolicy(nsINode* aNode) : mParentNode(aNode) {}
+
+void FeaturePolicy::InheritPolicy(FeaturePolicy* aParentPolicy) {
+  MOZ_ASSERT(aParentPolicy);
+
+  mInheritedDeniedFeatureNames.Clear();
+
+  RefPtr<FeaturePolicy> dest = this;
+  RefPtr<FeaturePolicy> src = aParentPolicy;
+
+  // Inherit origins which explicitly declared policy in chain
+  for (const Feature& featureInChain :
+       aParentPolicy->mDeclaredFeaturesInAncestorChain) {
+    dest->AppendToDeclaredAllowInAncestorChain(featureInChain);
+  }
+
+  FeaturePolicyUtils::ForEachFeature([dest, src](const char* aFeatureName) {
+    nsString featureName;
+    featureName.AppendASCII(aFeatureName);
+    // Store unsafe allows all (allow=*)
+    if (src->HasFeatureUnsafeAllowsAll(featureName)) {
+      dest->mParentAllowedAllFeatures.AppendElement(featureName);
+    }
+
+    // If the destination has a declared feature (via the HTTP header or 'allow'
+    // attribute) we allow the feature if the destination allows it and the
+    // parent allows its origin or the destinations' one.
+    if (dest->HasDeclaredFeature(featureName) &&
+        dest->AllowsFeatureInternal(featureName, dest->mDefaultOrigin)) {
+      if (!src->AllowsFeatureInternal(featureName, src->mDefaultOrigin) &&
+          !src->AllowsFeatureInternal(featureName, dest->mDefaultOrigin)) {
+        dest->SetInheritedDeniedFeature(featureName);
+      }
+      return;
+    }
+
+    // If there was not a declared feature, we allow the feature if the parent
+    // FeaturePolicy allows the current origin.
+    if (!src->AllowsFeatureInternal(featureName, dest->mDefaultOrigin)) {
+      dest->SetInheritedDeniedFeature(featureName);
+    }
+  });
+}
+
+void FeaturePolicy::SetInheritedDeniedFeature(const nsAString& aFeatureName) {
+  MOZ_ASSERT(!HasInheritedDeniedFeature(aFeatureName));
+  mInheritedDeniedFeatureNames.AppendElement(aFeatureName);
+}
+
+bool FeaturePolicy::HasInheritedDeniedFeature(
+    const nsAString& aFeatureName) const {
+  return mInheritedDeniedFeatureNames.Contains(aFeatureName);
+}
+
+bool FeaturePolicy::HasDeclaredFeature(const nsAString& aFeatureName) const {
+  for (const Feature& feature : mFeatures) {
+    if (feature.Name().Equals(aFeatureName)) {
+      return true;
+    }
+  }
+
+  return false;
+}
+
+bool FeaturePolicy::HasFeatureUnsafeAllowsAll(
+    const nsAString& aFeatureName) const {
+  for (const Feature& feature : mFeatures) {
+    if (feature.AllowsAll() && feature.Name().Equals(aFeatureName)) {
+      return true;
+    }
+  }
+
+  // We should look into parent too (for example, document of iframe which
+  // allows all, would be unsafe)
+  return mParentAllowedAllFeatures.Contains(aFeatureName);
+}
+
+void FeaturePolicy::AppendToDeclaredAllowInAncestorChain(
+    const Feature& aFeature) {
+  for (Feature& featureInChain : mDeclaredFeaturesInAncestorChain) {
+    if (featureInChain.Name().Equals(aFeature.Name())) {
+      MOZ_ASSERT(featureInChain.HasAllowList());
+
+      nsTArray<nsCOMPtr<nsIPrincipal>> list;
+      aFeature.GetAllowList(list);
+
+      for (nsIPrincipal* principal : list) {
+        featureInChain.AppendToAllowList(principal);
+      }
+      continue;
+    }
+  }
+
+  mDeclaredFeaturesInAncestorChain.AppendElement(aFeature);
+}
+
+bool FeaturePolicy::IsSameOriginAsSrc(nsIPrincipal* aPrincipal) const {
+  MOZ_ASSERT(aPrincipal);
+
+  if (!mSrcOrigin) {
+    return false;
+  }
+
+  return BasePrincipal::Cast(mSrcOrigin)
+      ->Subsumes(aPrincipal, BasePrincipal::ConsiderDocumentDomain);
+}
+
+void FeaturePolicy::SetDeclaredPolicy(Document* aDocument,
+                                      const nsAString& aPolicyString,
+                                      nsIPrincipal* aSelfOrigin,
+                                      nsIPrincipal* aSrcOrigin) {
+  ResetDeclaredPolicy();
+
+  mDeclaredString = aPolicyString;
+  mSelfOrigin = aSelfOrigin;
+  mSrcOrigin = aSrcOrigin;
+
+  Unused << NS_WARN_IF(!FeaturePolicyParser::ParseString(
+      aPolicyString, aDocument, aSelfOrigin, aSrcOrigin, mFeatures));
+
+  // Only store explicitly declared allowlist
+  for (const Feature& feature : mFeatures) {
+    if (feature.HasAllowList()) {
+      AppendToDeclaredAllowInAncestorChain(feature);
+    }
+  }
+}
+
+void FeaturePolicy::ResetDeclaredPolicy() {
+  mFeatures.Clear();
+  mDeclaredString.Truncate();
+  mSelfOrigin = nullptr;
+  mSrcOrigin = nullptr;
+  mDeclaredFeaturesInAncestorChain.Clear();
+  mAttributeEnabledFeatureNames.Clear();
+}
+
+JSObject* FeaturePolicy::WrapObject(JSContext* aCx,
+                                    JS::Handle<JSObject*> aGivenProto) {
+  return FeaturePolicy_Binding::Wrap(aCx, this, aGivenProto);
+}
+
+bool FeaturePolicy::AllowsFeature(const nsAString& aFeatureName,
+                                  const Optional<nsAString>& aOrigin) const {
+  nsCOMPtr<nsIPrincipal> origin;
+  if (aOrigin.WasPassed()) {
+    nsCOMPtr<nsIURI> uri;
+    nsresult rv = NS_NewURI(getter_AddRefs(uri), aOrigin.Value());
+    if (NS_FAILED(rv)) {
+      return false;
+    }
+    origin = BasePrincipal::CreateContentPrincipal(
+        uri, BasePrincipal::Cast(mDefaultOrigin)->OriginAttributesRef());
+  } else {
+    origin = mDefaultOrigin;
+  }
+
+  if (NS_WARN_IF(!origin)) {
+    return false;
+  }
+
+  return AllowsFeatureInternal(aFeatureName, origin);
+}
+
+bool FeaturePolicy::AllowsFeatureExplicitlyInAncestorChain(
+    const nsAString& aFeatureName, nsIPrincipal* aOrigin) const {
+  MOZ_ASSERT(aOrigin);
+
+  for (const Feature& feature : mDeclaredFeaturesInAncestorChain) {
+    if (feature.Name().Equals(aFeatureName)) {
+      return feature.AllowListContains(aOrigin);
+    }
+  }
+
+  return false;
+}
+
+bool FeaturePolicy::AllowsFeatureInternal(const nsAString& aFeatureName,
+                                          nsIPrincipal* aOrigin) const {
+  MOZ_ASSERT(aOrigin);
+
+  // Let's see if have to disable this feature because inherited policy.
+  if (HasInheritedDeniedFeature(aFeatureName)) {
+    return false;
+  }
+
+  for (const Feature& feature : mFeatures) {
+    if (feature.Name().Equals(aFeatureName)) {
+      return feature.Allows(aOrigin);
+    }
+  }
+
+  switch (FeaturePolicyUtils::DefaultAllowListFeature(aFeatureName)) {
+    case FeaturePolicyUtils::FeaturePolicyValue::eAll:
+      return true;
+
+    case FeaturePolicyUtils::FeaturePolicyValue::eSelf:
+      return BasePrincipal::Cast(mDefaultOrigin)
+          ->Subsumes(aOrigin, BasePrincipal::ConsiderDocumentDomain);
+
+    case FeaturePolicyUtils::FeaturePolicyValue::eNone:
+      return false;
+
+    default:
+      MOZ_CRASH("Unknown default value");
+  }
+
+  return false;
+}
+
+void FeaturePolicy::Features(nsTArray<nsString>& aFeatures) {
+  RefPtr<FeaturePolicy> self = this;
+  FeaturePolicyUtils::ForEachFeature(
+      [self, &aFeatures](const char* aFeatureName) {
+        nsString featureName;
+        featureName.AppendASCII(aFeatureName);
+        aFeatures.AppendElement(featureName);
+      });
+}
+
+void FeaturePolicy::AllowedFeatures(nsTArray<nsString>& aAllowedFeatures) {
+  RefPtr<FeaturePolicy> self = this;
+  FeaturePolicyUtils::ForEachFeature(
+      [self, &aAllowedFeatures](const char* aFeatureName) {
+        nsString featureName;
+        featureName.AppendASCII(aFeatureName);
+
+        if (self->AllowsFeatureInternal(featureName, self->mDefaultOrigin)) {
+          aAllowedFeatures.AppendElement(featureName);
+        }
+      });
+}
+
+void FeaturePolicy::GetAllowlistForFeature(const nsAString& aFeatureName,
+                                           nsTArray<nsString>& aList) const {
+  if (!AllowsFeatureInternal(aFeatureName, mDefaultOrigin)) {
+    return;
+  }
+
+  for (const Feature& feature : mFeatures) {
+    if (feature.Name().Equals(aFeatureName)) {
+      if (feature.AllowsAll()) {
+        aList.AppendElement(u"*"_ns);
+        return;
+      }
+
+      nsTArray<nsCOMPtr<nsIPrincipal>> list;
+      feature.GetAllowList(list);
+
+      for (nsIPrincipal* principal : list) {
+        nsAutoCString originNoSuffix;
+        nsresult rv = principal->GetOriginNoSuffix(originNoSuffix);
+        if (NS_WARN_IF(NS_FAILED(rv))) {
+          return;
+        }
+
+        aList.AppendElement(NS_ConvertUTF8toUTF16(originNoSuffix));
+      }
+      return;
+    }
+  }
+
+  switch (FeaturePolicyUtils::DefaultAllowListFeature(aFeatureName)) {
+    case FeaturePolicyUtils::FeaturePolicyValue::eAll:
+      aList.AppendElement(u"*"_ns);
+      return;
+
+    case FeaturePolicyUtils::FeaturePolicyValue::eSelf: {
+      nsAutoCString originNoSuffix;
+      nsresult rv = mDefaultOrigin->GetOriginNoSuffix(originNoSuffix);
+      if (NS_WARN_IF(NS_FAILED(rv))) {
+        return;
+      }
+
+      aList.AppendElement(NS_ConvertUTF8toUTF16(originNoSuffix));
+      return;
+    }
+
+    case FeaturePolicyUtils::FeaturePolicyValue::eNone:
+      return;
+
+    default:
+      MOZ_CRASH("Unknown default value");
+  }
+}
+
+void FeaturePolicy::MaybeSetAllowedPolicy(const nsAString& aFeatureName) {
+  MOZ_ASSERT(FeaturePolicyUtils::IsSupportedFeature(aFeatureName) ||
+             FeaturePolicyUtils::IsExperimentalFeature(aFeatureName));
+  // Skip if feature is in experimental phase
+  if (!StaticPrefs::dom_security_featurePolicy_experimental_enabled() &&
+      FeaturePolicyUtils::IsExperimentalFeature(aFeatureName)) {
+    return;
+  }
+
+  if (HasDeclaredFeature(aFeatureName)) {
+    return;
+  }
+
+  Feature feature(aFeatureName);
+  feature.SetAllowsAll();
+
+  mFeatures.AppendElement(feature);
+  mAttributeEnabledFeatureNames.AppendElement(aFeatureName);
+}
+
+}  // namespace mozilla::dom
diff --git a/dom/security/featurepolicy/FeaturePolicy.h b/dom/security/featurepolicy/FeaturePolicy.h
new file mode 100644
index 0000000000..65f5259749
--- /dev/null
+++ b/dom/security/featurepolicy/FeaturePolicy.h
@@ -0,0 +1,204 @@
+/* -*- 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/. */
+
+#ifndef mozilla_dom_FeaturePolicy_h
+#define mozilla_dom_FeaturePolicy_h
+
+#include "nsCycleCollectionParticipant.h"
+#include "nsIPrincipal.h"
+#include "nsStringFwd.h"
+#include "nsTArray.h"
+#include "nsWrapperCache.h"
+
+/**
+ * FeaturePolicy
+ * ~~~~~~~~~~~~~
+ *
+ * Each document and each HTMLIFrameElement have a FeaturePolicy object which is
+ * used to allow or deny features in their contexts.
+ *
+ * FeaturePolicy is composed by a set of directives configured by the
+ * 'Feature-Policy' HTTP Header and the 'allow' attribute in HTMLIFrameElements.
+ * Both header and attribute are parsed by FeaturePolicyParser which returns an
+ * array of Feature objects. Each Feature object has a feature name and one of
+ * these policies:
+ * - eNone - the feature is fully disabled.
+ * - eAll - the feature is allowed.
+ * - eAllowList - the feature is allowed for a list of origins.
+ *
+ * An interesting element of FeaturePolicy is the inheritance: each context
+ * inherits the feature-policy directives from the parent context, if it exists.
+ * When a context inherits a policy for feature X, it only knows if that feature
+ * is allowed or denied (it ignores the list of allowed origins for instance).
+ * This information is stored in an array of inherited feature strings because
+ * we care only to know when they are denied.
+ *
+ * FeaturePolicy can be reset if the 'allow' or 'src' attributes change in
+ * HTMLIFrameElements. 'src' attribute is important to compute correcly
+ * the features via FeaturePolicy 'src' keyword.
+ *
+ * When FeaturePolicy must decide if feature X is allowed or denied for the
+ * current origin, it checks if the parent context denied that feature.
+ * If not, it checks if there is a Feature object for that
+ * feature named X and if the origin is allowed or not.
+ *
+ * From a C++ point of view, use FeaturePolicyUtils to obtain the list of
+ * features and to check if they are allowed in the current context.
+ *
+ * dom.security.featurePolicy.header.enabled pref can be used to disable the
+ * HTTP header support.
+ **/
+
+class nsINode;
+
+namespace mozilla::dom {
+class Document;
+class Feature;
+template <typename T>
+class Optional;
+
+class FeaturePolicyUtils;
+
+class FeaturePolicy final : public nsISupports, public nsWrapperCache {
+  friend class FeaturePolicyUtils;
+
+ public:
+  NS_DECL_CYCLE_COLLECTING_ISUPPORTS
+  NS_DECL_CYCLE_COLLECTION_WRAPPERCACHE_CLASS(FeaturePolicy)
+
+  explicit FeaturePolicy(nsINode* aNode);
+
+  // A FeaturePolicy must have a default origin.
+  // This method must be called before any other exposed WebIDL method or before
+  // checking if a feature is allowed.
+  void SetDefaultOrigin(nsIPrincipal* aPrincipal) {
+    mDefaultOrigin = aPrincipal;
+  }
+
+  void SetSrcOrigin(nsIPrincipal* aPrincipal) { mSrcOrigin = aPrincipal; }
+
+  nsIPrincipal* DefaultOrigin() const { return mDefaultOrigin; }
+
+  // Inherits the policy from the 'parent' context if it exists.
+  void InheritPolicy(FeaturePolicy* aParentFeaturePolicy);
+
+  // Sets the declarative part of the policy. This can be from the HTTP header
+  // or for the 'allow' HTML attribute.
+  void SetDeclaredPolicy(mozilla::dom::Document* aDocument,
+                         const nsAString& aPolicyString,
+                         nsIPrincipal* aSelfOrigin, nsIPrincipal* aSrcOrigin);
+
+  // This method creates a policy for aFeatureName allowing it to '*' if it
+  // doesn't exist yet. It's used by HTMLIFrameElement to enable features by
+  // attributes.
+  void MaybeSetAllowedPolicy(const nsAString& aFeatureName);
+
+  // Clears all the declarative policy directives. This is needed when the
+  // 'allow' attribute or the 'src' attribute change for HTMLIFrameElement's
+  // policy.
+  void ResetDeclaredPolicy();
+
+  // This method appends a feature to in-chain declared allowlist. If the name's
+  // feature existed in the list, we only need to append the allowlist of new
+  // feature to the existed one.
+  void AppendToDeclaredAllowInAncestorChain(const Feature& aFeature);
+
+  // This method returns true if aFeatureName is declared as "*" (allow all)
+  // in parent.
+  bool HasFeatureUnsafeAllowsAll(const nsAString& aFeatureName) const;
+
+  // This method returns true if the aFeatureName is allowed for aOrigin
+  // explicitly in ancestor chain,
+  bool AllowsFeatureExplicitlyInAncestorChain(const nsAString& aFeatureName,
+                                              nsIPrincipal* aOrigin) const;
+
+  bool IsSameOriginAsSrc(nsIPrincipal* aPrincipal) const;
+
+  // WebIDL internal methods.
+
+  JSObject* WrapObject(JSContext* aCx,
+                       JS::Handle<JSObject*> aGivenProto) override;
+
+  nsINode* GetParentObject() const { return mParentNode; }
+
+  // WebIDL explosed methods.
+
+  bool AllowsFeature(const nsAString& aFeatureName,
+                     const Optional<nsAString>& aOrigin) const;
+
+  void Features(nsTArray<nsString>& aFeatures);
+
+  void AllowedFeatures(nsTArray<nsString>& aAllowedFeatures);
+
+  void GetAllowlistForFeature(const nsAString& aFeatureName,
+                              nsTArray<nsString>& aList) const;
+
+  const nsTArray<nsString>& InheritedDeniedFeatureNames() const {
+    return mInheritedDeniedFeatureNames;
+  }
+
+  const nsTArray<nsString>& AttributeEnabledFeatureNames() const {
+    return mAttributeEnabledFeatureNames;
+  }
+
+  void SetInheritedDeniedFeatureNames(
+      const nsTArray<nsString>& aInheritedDeniedFeatureNames) {
+    mInheritedDeniedFeatureNames = aInheritedDeniedFeatureNames.Clone();
+  }
+
+  const nsAString& DeclaredString() const { return mDeclaredString; }
+
+  nsIPrincipal* GetSelfOrigin() const { return mSelfOrigin; }
+  nsIPrincipal* GetSrcOrigin() const { return mSrcOrigin; }
+
+ private:
+  ~FeaturePolicy() = default;
+
+  // This method returns true if the aFeatureName is allowed for aOrigin,
+  // following the feature-policy directives. See the comment at the top of this
+  // file.
+  bool AllowsFeatureInternal(const nsAString& aFeatureName,
+                             nsIPrincipal* aOrigin) const;
+
+  // Inherits a single denied feature from the parent context.
+  void SetInheritedDeniedFeature(const nsAString& aFeatureName);
+
+  bool HasInheritedDeniedFeature(const nsAString& aFeatureName) const;
+
+  // This returns true if we have a declared feature policy for aFeatureName.
+  bool HasDeclaredFeature(const nsAString& aFeatureName) const;
+
+  nsINode* mParentNode;
+
+  // This is set in sub-contexts when the parent blocks some feature for the
+  // current context.
+  nsTArray<nsString> mInheritedDeniedFeatureNames;
+
+  // The list of features that have been enabled via MaybeSetAllowedPolicy.
+  nsTArray<nsString> mAttributeEnabledFeatureNames;
+
+  // This is set of feature names when the parent allows all for that feature.
+  nsTArray<nsString> mParentAllowedAllFeatures;
+
+  // The explicitly declared policy contains allowlist as a set of origins
+  // except 'none' and '*'. This set contains all explicitly declared policies
+  // in ancestor chain
+  nsTArray<Feature> mDeclaredFeaturesInAncestorChain;
+
+  // Feature policy for the current context.
+  nsTArray<Feature> mFeatures;
+
+  // Declared string represents Feature policy.
+  nsString mDeclaredString;
+
+  nsCOMPtr<nsIPrincipal> mDefaultOrigin;
+  nsCOMPtr<nsIPrincipal> mSelfOrigin;
+  nsCOMPtr<nsIPrincipal> mSrcOrigin;
+};
+
+}  // namespace mozilla::dom
+
+#endif  // mozilla_dom_FeaturePolicy_h
diff --git a/dom/security/featurepolicy/FeaturePolicyParser.cpp b/dom/security/featurepolicy/FeaturePolicyParser.cpp
new file mode 100644
index 0000000000..8ab95420aa
--- /dev/null
+++ b/dom/security/featurepolicy/FeaturePolicyParser.cpp
@@ -0,0 +1,157 @@
+/* -*- 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 "FeaturePolicyParser.h"
+
+#include "mozilla/BasePrincipal.h"
+#include "mozilla/dom/Feature.h"
+#include "mozilla/dom/FeaturePolicyUtils.h"
+#include "mozilla/dom/PolicyTokenizer.h"
+#include "nsIScriptError.h"
+#include "nsIURI.h"
+#include "nsNetUtil.h"
+
+namespace mozilla::dom {
+
+namespace {
+
+void ReportToConsoleUnsupportedFeature(Document* aDocument,
+                                       const nsString& aFeatureName) {
+  if (!aDocument) {
+    return;
+  }
+
+  AutoTArray<nsString, 1> params = {aFeatureName};
+
+  nsContentUtils::ReportToConsole(
+      nsIScriptError::warningFlag, "Feature Policy"_ns, aDocument,
+      nsContentUtils::eSECURITY_PROPERTIES,
+      "FeaturePolicyUnsupportedFeatureName", params);
+}
+
+void ReportToConsoleInvalidEmptyAllowValue(Document* aDocument,
+                                           const nsString& aFeatureName) {
+  if (!aDocument) {
+    return;
+  }
+
+  AutoTArray<nsString, 1> params = {aFeatureName};
+
+  nsContentUtils::ReportToConsole(
+      nsIScriptError::warningFlag, "Feature Policy"_ns, aDocument,
+      nsContentUtils::eSECURITY_PROPERTIES,
+      "FeaturePolicyInvalidEmptyAllowValue", params);
+}
+
+void ReportToConsoleInvalidAllowValue(Document* aDocument,
+                                      const nsString& aValue) {
+  if (!aDocument) {
+    return;
+  }
+
+  AutoTArray<nsString, 1> params = {aValue};
+
+  nsContentUtils::ReportToConsole(nsIScriptError::warningFlag,
+                                  "Feature Policy"_ns, aDocument,
+                                  nsContentUtils::eSECURITY_PROPERTIES,
+                                  "FeaturePolicyInvalidAllowValue", params);
+}
+
+}  // namespace
+
+/* static */
+bool FeaturePolicyParser::ParseString(const nsAString& aPolicy,
+                                      Document* aDocument,
+                                      nsIPrincipal* aSelfOrigin,
+                                      nsIPrincipal* aSrcOrigin,
+                                      nsTArray<Feature>& aParsedFeatures) {
+  MOZ_ASSERT(aSelfOrigin);
+
+  nsTArray<CopyableTArray<nsString>> tokens;
+  PolicyTokenizer::tokenizePolicy(aPolicy, tokens);
+
+  nsTArray<Feature> parsedFeatures;
+
+  for (const nsTArray<nsString>& featureTokens : tokens) {
+    if (featureTokens.IsEmpty()) {
+      continue;
+    }
+
+    if (!FeaturePolicyUtils::IsSupportedFeature(featureTokens[0])) {
+      ReportToConsoleUnsupportedFeature(aDocument, featureTokens[0]);
+      continue;
+    }
+
+    Feature feature(featureTokens[0]);
+
+    if (featureTokens.Length() == 1) {
+      if (aSrcOrigin) {
+        feature.AppendToAllowList(aSrcOrigin);
+      } else {
+        ReportToConsoleInvalidEmptyAllowValue(aDocument, featureTokens[0]);
+        continue;
+      }
+    } else {
+      // we gotta start at 1 here
+      for (uint32_t i = 1; i < featureTokens.Length(); ++i) {
+        const nsString& curVal = featureTokens[i];
+        if (curVal.LowerCaseEqualsASCII("'none'")) {
+          feature.SetAllowsNone();
+          break;
+        }
+
+        if (curVal.EqualsLiteral("*")) {
+          feature.SetAllowsAll();
+          break;
+        }
+
+        if (curVal.LowerCaseEqualsASCII("'self'")) {
+          feature.AppendToAllowList(aSelfOrigin);
+          continue;
+        }
+
+        if (aSrcOrigin && curVal.LowerCaseEqualsASCII("'src'")) {
+          feature.AppendToAllowList(aSrcOrigin);
+          continue;
+        }
+
+        nsCOMPtr<nsIURI> uri;
+        nsresult rv = NS_NewURI(getter_AddRefs(uri), curVal);
+        if (NS_FAILED(rv)) {
+          ReportToConsoleInvalidAllowValue(aDocument, curVal);
+          continue;
+        }
+
+        nsCOMPtr<nsIPrincipal> origin = BasePrincipal::CreateContentPrincipal(
+            uri, BasePrincipal::Cast(aSelfOrigin)->OriginAttributesRef());
+        if (NS_WARN_IF(!origin)) {
+          ReportToConsoleInvalidAllowValue(aDocument, curVal);
+          continue;
+        }
+
+        feature.AppendToAllowList(origin);
+      }
+    }
+
+    // No duplicate!
+    bool found = false;
+    for (const Feature& parsedFeature : parsedFeatures) {
+      if (parsedFeature.Name() == feature.Name()) {
+        found = true;
+        break;
+      }
+    }
+
+    if (!found) {
+      parsedFeatures.AppendElement(feature);
+    }
+  }
+
+  aParsedFeatures = std::move(parsedFeatures);
+  return true;
+}
+
+}  // namespace mozilla::dom
diff --git a/dom/security/featurepolicy/FeaturePolicyParser.h b/dom/security/featurepolicy/FeaturePolicyParser.h
new file mode 100644
index 0000000000..a60a391a78
--- /dev/null
+++ b/dom/security/featurepolicy/FeaturePolicyParser.h
@@ -0,0 +1,30 @@
+/* -*- 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/. */
+
+#ifndef mozilla_dom_FeaturePolicyParser_h
+#define mozilla_dom_FeaturePolicyParser_h
+
+#include "nsString.h"
+
+class nsIPrincipal;
+
+namespace mozilla::dom {
+
+class Document;
+class Feature;
+
+class FeaturePolicyParser final {
+ public:
+  // aSelfOrigin must not be null. if aSrcOrigin is null, the parsing will not
+  // support 'src' as valid allow directive value.
+  static bool ParseString(const nsAString& aPolicy, Document* aDocument,
+                          nsIPrincipal* aSelfOrigin, nsIPrincipal* aSrcOrigin,
+                          nsTArray<Feature>& aParsedFeatures);
+};
+
+}  // namespace mozilla::dom
+
+#endif  // mozilla_dom_FeaturePolicyParser_h
diff --git a/dom/security/featurepolicy/FeaturePolicyUtils.cpp b/dom/security/featurepolicy/FeaturePolicyUtils.cpp
new file mode 100644
index 0000000000..1b2a383642
--- /dev/null
+++ b/dom/security/featurepolicy/FeaturePolicyUtils.cpp
@@ -0,0 +1,309 @@
+/* -*- 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 "FeaturePolicyUtils.h"
+#include "nsIOService.h"
+
+#include "mozilla/dom/DOMTypes.h"
+#include "mozilla/ipc/IPDLParamTraits.h"
+#include "mozilla/dom/FeaturePolicyViolationReportBody.h"
+#include "mozilla/dom/ReportingUtils.h"
+#include "mozilla/StaticPrefs_dom.h"
+#include "mozilla/dom/Document.h"
+#include "nsContentUtils.h"
+#include "nsJSUtils.h"
+
+namespace mozilla {
+namespace dom {
+
+struct FeatureMap {
+  const char* mFeatureName;
+  FeaturePolicyUtils::FeaturePolicyValue mDefaultAllowList;
+};
+
+/*
+ * IMPORTANT: Do not change this list without review from a DOM peer _AND_ a
+ * DOM Security peer!
+ */
+static FeatureMap sSupportedFeatures[] = {
+    {"camera", FeaturePolicyUtils::FeaturePolicyValue::eSelf},
+    {"geolocation", FeaturePolicyUtils::FeaturePolicyValue::eSelf},
+    {"microphone", FeaturePolicyUtils::FeaturePolicyValue::eSelf},
+    {"display-capture", FeaturePolicyUtils::FeaturePolicyValue::eSelf},
+    {"fullscreen", FeaturePolicyUtils::FeaturePolicyValue::eSelf},
+    {"web-share", FeaturePolicyUtils::FeaturePolicyValue::eSelf},
+    {"gamepad", FeaturePolicyUtils::FeaturePolicyValue::eAll},
+    {"speaker-selection", FeaturePolicyUtils::FeaturePolicyValue::eSelf},
+};
+
+/*
+ * This is experimental features list, which is disabled by default by pref
+ * dom.security.featurePolicy.experimental.enabled.
+ */
+static FeatureMap sExperimentalFeatures[] = {
+    // We don't support 'autoplay' for now, because it would be overwrote by
+    // 'user-gesture-activation' policy. However, we can still keep it in the
+    // list as we might start supporting it after we use different autoplay
+    // policy.
+    {"autoplay", FeaturePolicyUtils::FeaturePolicyValue::eAll},
+    {"encrypted-media", FeaturePolicyUtils::FeaturePolicyValue::eAll},
+    {"midi", FeaturePolicyUtils::FeaturePolicyValue::eSelf},
+    {"payment", FeaturePolicyUtils::FeaturePolicyValue::eAll},
+    {"document-domain", FeaturePolicyUtils::FeaturePolicyValue::eAll},
+    {"vr", FeaturePolicyUtils::FeaturePolicyValue::eAll},
+    // https://immersive-web.github.io/webxr/#feature-policy
+    {"xr-spatial-tracking", FeaturePolicyUtils::FeaturePolicyValue::eSelf},
+};
+
+/* static */
+bool FeaturePolicyUtils::IsExperimentalFeature(const nsAString& aFeatureName) {
+  uint32_t numFeatures =
+      (sizeof(sExperimentalFeatures) / sizeof(sExperimentalFeatures[0]));
+  for (uint32_t i = 0; i < numFeatures; ++i) {
+    if (aFeatureName.LowerCaseEqualsASCII(
+            sExperimentalFeatures[i].mFeatureName)) {
+      return true;
+    }
+  }
+
+  return false;
+}
+
+/* static */
+bool FeaturePolicyUtils::IsSupportedFeature(const nsAString& aFeatureName) {
+  uint32_t numFeatures =
+      (sizeof(sSupportedFeatures) / sizeof(sSupportedFeatures[0]));
+  for (uint32_t i = 0; i < numFeatures; ++i) {
+    if (aFeatureName.LowerCaseEqualsASCII(sSupportedFeatures[i].mFeatureName)) {
+      return true;
+    }
+  }
+
+  return StaticPrefs::dom_security_featurePolicy_experimental_enabled() &&
+         IsExperimentalFeature(aFeatureName);
+}
+
+/* static */
+void FeaturePolicyUtils::ForEachFeature(
+    const std::function<void(const char*)>& aCallback) {
+  uint32_t numFeatures =
+      (sizeof(sSupportedFeatures) / sizeof(sSupportedFeatures[0]));
+  for (uint32_t i = 0; i < numFeatures; ++i) {
+    aCallback(sSupportedFeatures[i].mFeatureName);
+  }
+
+  if (StaticPrefs::dom_security_featurePolicy_experimental_enabled()) {
+    numFeatures =
+        (sizeof(sExperimentalFeatures) / sizeof(sExperimentalFeatures[0]));
+    for (uint32_t i = 0; i < numFeatures; ++i) {
+      aCallback(sExperimentalFeatures[i].mFeatureName);
+    }
+  }
+}
+
+/* static */ FeaturePolicyUtils::FeaturePolicyValue
+FeaturePolicyUtils::DefaultAllowListFeature(const nsAString& aFeatureName) {
+  uint32_t numFeatures =
+      (sizeof(sSupportedFeatures) / sizeof(sSupportedFeatures[0]));
+  for (uint32_t i = 0; i < numFeatures; ++i) {
+    if (aFeatureName.LowerCaseEqualsASCII(sSupportedFeatures[i].mFeatureName)) {
+      return sSupportedFeatures[i].mDefaultAllowList;
+    }
+  }
+
+  if (StaticPrefs::dom_security_featurePolicy_experimental_enabled()) {
+    numFeatures =
+        (sizeof(sExperimentalFeatures) / sizeof(sExperimentalFeatures[0]));
+    for (uint32_t i = 0; i < numFeatures; ++i) {
+      if (aFeatureName.LowerCaseEqualsASCII(
+              sExperimentalFeatures[i].mFeatureName)) {
+        return sExperimentalFeatures[i].mDefaultAllowList;
+      }
+    }
+  }
+
+  return FeaturePolicyValue::eNone;
+}
+
+static bool IsSameOriginAsTop(Document* aDocument) {
+  MOZ_ASSERT(aDocument);
+
+  BrowsingContext* browsingContext = aDocument->GetBrowsingContext();
+  if (!browsingContext) {
+    return false;
+  }
+
+  nsPIDOMWindowOuter* topWindow = browsingContext->Top()->GetDOMWindow();
+  if (!topWindow) {
+    // If we don't have a DOMWindow, We are not in same origin.
+    return false;
+  }
+
+  Document* topLevelDocument = topWindow->GetExtantDoc();
+  if (!topLevelDocument) {
+    return false;
+  }
+
+  return NS_SUCCEEDED(
+      nsContentUtils::CheckSameOrigin(topLevelDocument, aDocument));
+}
+
+/* static */
+bool FeaturePolicyUtils::IsFeatureUnsafeAllowedAll(
+    Document* aDocument, const nsAString& aFeatureName) {
+  MOZ_ASSERT(aDocument);
+
+  if (!aDocument->IsHTMLDocument()) {
+    return false;
+  }
+
+  FeaturePolicy* policy = aDocument->FeaturePolicy();
+  MOZ_ASSERT(policy);
+
+  return policy->HasFeatureUnsafeAllowsAll(aFeatureName) &&
+         !policy->IsSameOriginAsSrc(aDocument->NodePrincipal()) &&
+         !policy->AllowsFeatureExplicitlyInAncestorChain(
+             aFeatureName, policy->DefaultOrigin()) &&
+         !IsSameOriginAsTop(aDocument);
+}
+
+/* static */
+bool FeaturePolicyUtils::IsFeatureAllowed(Document* aDocument,
+                                          const nsAString& aFeatureName) {
+  MOZ_ASSERT(aDocument);
+
+  // Skip apply features in experimental phase
+  if (!StaticPrefs::dom_security_featurePolicy_experimental_enabled() &&
+      IsExperimentalFeature(aFeatureName)) {
+    return true;
+  }
+
+  FeaturePolicy* policy = aDocument->FeaturePolicy();
+  MOZ_ASSERT(policy);
+
+  if (policy->AllowsFeatureInternal(aFeatureName, policy->DefaultOrigin())) {
+    return true;
+  }
+
+  ReportViolation(aDocument, aFeatureName);
+  return false;
+}
+
+/* static */
+void FeaturePolicyUtils::ReportViolation(Document* aDocument,
+                                         const nsAString& aFeatureName) {
+  MOZ_ASSERT(aDocument);
+
+  nsCOMPtr<nsIURI> uri = aDocument->GetDocumentURI();
+  if (NS_WARN_IF(!uri)) {
+    return;
+  }
+
+  // Strip the URL of any possible username/password and make it ready to be
+  // presented in the UI.
+  nsCOMPtr<nsIURI> exposableURI = net::nsIOService::CreateExposableURI(uri);
+  nsAutoCString spec;
+  nsresult rv = exposableURI->GetSpec(spec);
+  if (NS_WARN_IF(NS_FAILED(rv))) {
+    return;
+  }
+  JSContext* cx = nsContentUtils::GetCurrentJSContext();
+  if (NS_WARN_IF(!cx)) {
+    return;
+  }
+
+  nsAutoString fileName;
+  Nullable<int32_t> lineNumber;
+  Nullable<int32_t> columnNumber;
+  uint32_t line = 0;
+  uint32_t column = 0;
+  if (nsJSUtils::GetCallingLocation(cx, fileName, &line, &column)) {
+    lineNumber.SetValue(static_cast<int32_t>(line));
+    columnNumber.SetValue(static_cast<int32_t>(column));
+  }
+
+  nsPIDOMWindowInner* window = aDocument->GetInnerWindow();
+  if (NS_WARN_IF(!window)) {
+    return;
+  }
+
+  RefPtr<FeaturePolicyViolationReportBody> body =
+      new FeaturePolicyViolationReportBody(window->AsGlobal(), aFeatureName,
+                                           fileName, lineNumber, columnNumber,
+                                           u"enforce"_ns);
+
+  ReportingUtils::Report(window->AsGlobal(), nsGkAtoms::featurePolicyViolation,
+                         u"default"_ns, NS_ConvertUTF8toUTF16(spec), body);
+}
+
+}  // namespace dom
+
+namespace ipc {
+void IPDLParamTraits<dom::FeaturePolicy*>::Write(IPC::MessageWriter* aWriter,
+                                                 IProtocol* aActor,
+                                                 dom::FeaturePolicy* aParam) {
+  if (!aParam) {
+    WriteIPDLParam(aWriter, aActor, false);
+    return;
+  }
+
+  WriteIPDLParam(aWriter, aActor, true);
+
+  dom::FeaturePolicyInfo info;
+  info.defaultOrigin() = aParam->DefaultOrigin();
+  info.selfOrigin() = aParam->GetSelfOrigin();
+  info.srcOrigin() = aParam->GetSrcOrigin();
+
+  info.declaredString() = aParam->DeclaredString();
+  info.inheritedDeniedFeatureNames() =
+      aParam->InheritedDeniedFeatureNames().Clone();
+  info.attributeEnabledFeatureNames() =
+      aParam->AttributeEnabledFeatureNames().Clone();
+
+  WriteIPDLParam(aWriter, aActor, info);
+}
+
+bool IPDLParamTraits<dom::FeaturePolicy*>::Read(
+    IPC::MessageReader* aReader, IProtocol* aActor,
+    RefPtr<dom::FeaturePolicy>* aResult) {
+  *aResult = nullptr;
+  bool notnull = false;
+  if (!ReadIPDLParam(aReader, aActor, &notnull)) {
+    return false;
+  }
+
+  if (!notnull) {
+    return true;
+  }
+
+  dom::FeaturePolicyInfo info;
+  if (!ReadIPDLParam(aReader, aActor, &info)) {
+    return false;
+  }
+
+  // Note that we only do IPC for feature policy to inherit policy from parent
+  // to child document. That does not need to bind feature policy with a node.
+  RefPtr<dom::FeaturePolicy> featurePolicy = new dom::FeaturePolicy(nullptr);
+  featurePolicy->SetDefaultOrigin(info.defaultOrigin());
+  featurePolicy->SetInheritedDeniedFeatureNames(
+      info.inheritedDeniedFeatureNames());
+
+  const auto& declaredString = info.declaredString();
+  if (info.selfOrigin() && !declaredString.IsEmpty()) {
+    featurePolicy->SetDeclaredPolicy(nullptr, declaredString, info.selfOrigin(),
+                                     info.srcOrigin());
+  }
+
+  for (auto& featureName : info.attributeEnabledFeatureNames()) {
+    featurePolicy->MaybeSetAllowedPolicy(featureName);
+  }
+
+  *aResult = std::move(featurePolicy);
+  return true;
+}
+}  // namespace ipc
+
+}  // namespace mozilla
diff --git a/dom/security/featurepolicy/FeaturePolicyUtils.h b/dom/security/featurepolicy/FeaturePolicyUtils.h
new file mode 100644
index 0000000000..380806433d
--- /dev/null
+++ b/dom/security/featurepolicy/FeaturePolicyUtils.h
@@ -0,0 +1,91 @@
+/* -*- 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/. */
+
+#ifndef mozilla_dom_FeaturePolicyUtils_h
+#define mozilla_dom_FeaturePolicyUtils_h
+
+#include "nsString.h"
+#include <functional>
+
+#include "mozilla/dom/FeaturePolicy.h"
+
+class PickleIterator;
+
+namespace IPC {
+class Message;
+class MessageReader;
+class MessageWriter;
+}  // namespace IPC
+
+namespace mozilla {
+namespace dom {
+
+class Document;
+
+class FeaturePolicyUtils final {
+ public:
+  enum FeaturePolicyValue {
+    // Feature always allowed.
+    eAll,
+
+    // Feature allowed for documents that are same-origin with this one.
+    eSelf,
+
+    // Feature denied.
+    eNone,
+  };
+
+  // This method returns true if aFeatureName is allowed for aDocument.
+  // Use this method everywhere you need to check feature-policy directives.
+  static bool IsFeatureAllowed(Document* aDocument,
+                               const nsAString& aFeatureName);
+
+  // Returns true if aFeatureName is a known feature policy name.
+  static bool IsSupportedFeature(const nsAString& aFeatureName);
+
+  // Returns true if aFeatureName is a experimental feature policy name.
+  static bool IsExperimentalFeature(const nsAString& aFeatureName);
+
+  // Runs aCallback for each known feature policy, with the feature name as
+  // argument.
+  static void ForEachFeature(const std::function<void(const char*)>& aCallback);
+
+  // Returns the default policy value for aFeatureName.
+  static FeaturePolicyValue DefaultAllowListFeature(
+      const nsAString& aFeatureName);
+
+  // This method returns true if aFeatureName is in unsafe allowed "*" case.
+  // We are in "unsafe" case when there is 'allow "*"' presents for an origin
+  // that's not presented in the ancestor feature policy chain, via src, via
+  // explicitly listed in allow, and not being the top-level origin.
+  static bool IsFeatureUnsafeAllowedAll(Document* aDocument,
+                                        const nsAString& aFeatureName);
+
+ private:
+  static void ReportViolation(Document* aDocument,
+                              const nsAString& aFeatureName);
+};
+
+}  // namespace dom
+
+namespace ipc {
+
+class IProtocol;
+
+template <typename T>
+struct IPDLParamTraits;
+
+template <>
+struct IPDLParamTraits<mozilla::dom::FeaturePolicy*> {
+  static void Write(IPC::MessageWriter* aWriter, IProtocol* aActor,
+                    mozilla::dom::FeaturePolicy* aParam);
+  static bool Read(IPC::MessageReader* aReader, IProtocol* aActor,
+                   RefPtr<mozilla::dom::FeaturePolicy>* aResult);
+};
+}  // namespace ipc
+}  // namespace mozilla
+
+#endif  // mozilla_dom_FeaturePolicyUtils_h
diff --git a/dom/security/featurepolicy/fuzztest/fp_fuzzer.cpp b/dom/security/featurepolicy/fuzztest/fp_fuzzer.cpp
new file mode 100644
index 0000000000..25f7dc8d41
--- /dev/null
+++ b/dom/security/featurepolicy/fuzztest/fp_fuzzer.cpp
@@ -0,0 +1,67 @@
+/* -*- 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 https://mozilla.org/MPL/2.0/. */
+
+#include "FuzzingInterface.h"
+#include "mozilla/BasePrincipal.h"
+#include "mozilla/dom/Feature.h"
+#include "mozilla/dom/FeaturePolicyParser.h"
+#include "nsNetUtil.h"
+#include "nsStringFwd.h"
+#include "nsTArray.h"
+
+using namespace mozilla;
+using namespace mozilla::dom;
+
+static nsCOMPtr<nsIPrincipal> selfURIPrincipal;
+static nsCOMPtr<nsIURI> selfURI;
+
+static int LVVMFuzzerInitTest(int* argc, char*** argv) {
+  nsresult ret;
+  ret = NS_NewURI(getter_AddRefs(selfURI), "http://selfuri.com");
+  if (ret != NS_OK) {
+    MOZ_CRASH("NS_NewURI failed.");
+  }
+
+  mozilla::OriginAttributes attrs;
+  selfURIPrincipal =
+      mozilla::BasePrincipal::CreateContentPrincipal(selfURI, attrs);
+  if (!selfURIPrincipal) {
+    MOZ_CRASH("CreateContentPrincipal failed.");
+  }
+  return 0;
+}
+
+static int LLVMFuzzerTestOneInput(const uint8_t* data, size_t size) {
+  if (!size) {
+    return 0;
+  }
+  nsTArray<Feature> parsedFeatures;
+
+  NS_ConvertASCIItoUTF16 policy(reinterpret_cast<const char*>(data), size);
+  if (!policy.get()) return 0;
+
+  FeaturePolicyParser::ParseString(policy, nullptr, selfURIPrincipal,
+                                   selfURIPrincipal, parsedFeatures);
+
+  for (const Feature& feature : parsedFeatures) {
+    nsTArray<nsCOMPtr<nsIPrincipal>> list;
+    feature.GetAllowList(list);
+
+    for (nsIPrincipal* principal : list) {
+      nsAutoCString originNoSuffix;
+      nsresult rv = principal->GetOriginNoSuffix(originNoSuffix);
+      if (NS_WARN_IF(NS_FAILED(rv))) {
+        return 0;
+      }
+      printf("%s - %s\n", NS_ConvertUTF16toUTF8(feature.Name()).get(),
+             originNoSuffix.get());
+    }
+  }
+  return 0;
+}
+
+MOZ_FUZZING_INTERFACE_RAW(LVVMFuzzerInitTest, LLVMFuzzerTestOneInput,
+                          FeaturePolicyParser);
diff --git a/dom/security/featurepolicy/fuzztest/fp_fuzzer.dict b/dom/security/featurepolicy/fuzztest/fp_fuzzer.dict
new file mode 100644
index 0000000000..e95508bf8e
--- /dev/null
+++ b/dom/security/featurepolicy/fuzztest/fp_fuzzer.dict
@@ -0,0 +1,54 @@
+# tokens
+"'"
+";"
+
+### https://www.w3.org/TR/{CSP,CSP2,CSP3}/
+# directive names
+"accelerometer"
+"ambient-light-sensor"
+"autoplay"
+"battery"
+"camera"
+"display-capture"
+"document-domain"
+"encrypted-media"
+"execution-while-not-rendered"
+"execution-while-out-of-viewport"
+"fullscreen
+"geolocation
+"gyroscope"
+"layout-animations"
+"legacy-image-formats"
+"magnetometer"
+"microphone"
+"midi"
+"navigation-override"
+"oversized-images"
+"payment"
+"picture-in-picture"
+"publickey-credentials"
+"sync-xhr"
+"usb"
+"vr"
+"wake-lock"
+"xr-spatial-tracking"
+
+# directive values
+"'self'"
+"'none'"
+"'src''"
+*
+
+
+# URI components
+"https:"
+"ws:"
+"blob:"
+"data:"
+"filesystem:"
+"javascript:"
+"http://"
+"selfuri.com"
+"127.0.0.1"
+"::1"
+https://example.com
\ No newline at end of file
diff --git a/dom/security/featurepolicy/fuzztest/moz.build b/dom/security/featurepolicy/fuzztest/moz.build
new file mode 100644
index 0000000000..ea577e8339
--- /dev/null
+++ b/dom/security/featurepolicy/fuzztest/moz.build
@@ -0,0 +1,18 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# 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/.
+
+Library("FuzzingFeaturePolicy")
+
+LOCAL_INCLUDES += [
+    "/dom/security/featurepolicy",
+    "/netwerk/base",
+]
+
+include("/tools/fuzzing/libfuzzer-config.mozbuild")
+
+SOURCES += ["fp_fuzzer.cpp"]
+
+FINAL_LIBRARY = "xul-gtest"
diff --git a/dom/security/featurepolicy/moz.build b/dom/security/featurepolicy/moz.build
new file mode 100644
index 0000000000..40277836ad
--- /dev/null
+++ b/dom/security/featurepolicy/moz.build
@@ -0,0 +1,36 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# 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/.
+
+with Files("**"):
+    BUG_COMPONENT = ("Core", "DOM: Security")
+
+TEST_DIRS += ["test/gtest"]
+MOCHITEST_MANIFESTS += ["test/mochitest/mochitest.ini"]
+
+EXPORTS.mozilla.dom += [
+    "Feature.h",
+    "FeaturePolicy.h",
+    "FeaturePolicyParser.h",
+    "FeaturePolicyUtils.h",
+]
+
+UNIFIED_SOURCES += [
+    "Feature.cpp",
+    "FeaturePolicy.cpp",
+    "FeaturePolicyParser.cpp",
+    "FeaturePolicyUtils.cpp",
+]
+
+LOCAL_INCLUDES += [
+    "/netwerk/base",
+]
+include("/ipc/chromium/chromium-config.mozbuild")
+include("/tools/fuzzing/libfuzzer-config.mozbuild")
+
+FINAL_LIBRARY = "xul"
+
+if CONFIG["FUZZING_INTERFACES"]:
+    TEST_DIRS += ["fuzztest"]
diff --git a/dom/security/featurepolicy/test/gtest/TestFeaturePolicyParser.cpp b/dom/security/featurepolicy/test/gtest/TestFeaturePolicyParser.cpp
new file mode 100644
index 0000000000..3e58971c9b
--- /dev/null
+++ b/dom/security/featurepolicy/test/gtest/TestFeaturePolicyParser.cpp
@@ -0,0 +1,162 @@
+/* -*- 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 "gtest/gtest.h"
+#include "mozilla/BasePrincipal.h"
+#include "mozilla/dom/Feature.h"
+#include "mozilla/dom/FeaturePolicyParser.h"
+#include "nsNetUtil.h"
+#include "nsTArray.h"
+
+using namespace mozilla;
+using namespace mozilla::dom;
+
+#define URL_SELF "https://example.com"_ns
+#define URL_EXAMPLE_COM "http://example.com"_ns
+#define URL_EXAMPLE_NET "http://example.net"_ns
+
+void CheckParser(const nsAString& aInput, bool aExpectedResults,
+                 uint32_t aExpectedFeatures,
+                 nsTArray<Feature>& aParsedFeatures) {
+  nsCOMPtr<nsIPrincipal> principal =
+      mozilla::BasePrincipal::CreateContentPrincipal(URL_SELF);
+  nsTArray<Feature> parsedFeatures;
+  ASSERT_TRUE(FeaturePolicyParser::ParseString(aInput, nullptr, principal,
+                                               principal, parsedFeatures) ==
+              aExpectedResults);
+  ASSERT_TRUE(parsedFeatures.Length() == aExpectedFeatures);
+
+  aParsedFeatures = std::move(parsedFeatures);
+}
+
+TEST(FeaturePolicyParser, Basic)
+{
+  nsCOMPtr<nsIPrincipal> selfPrincipal =
+      mozilla::BasePrincipal::CreateContentPrincipal(URL_SELF);
+  nsCOMPtr<nsIPrincipal> exampleComPrincipal =
+      mozilla::BasePrincipal::CreateContentPrincipal(URL_EXAMPLE_COM);
+  nsCOMPtr<nsIPrincipal> exampleNetPrincipal =
+      mozilla::BasePrincipal::CreateContentPrincipal(URL_EXAMPLE_NET);
+
+  nsTArray<Feature> parsedFeatures;
+
+  // Empty string is a valid policy.
+  CheckParser(u""_ns, true, 0, parsedFeatures);
+
+  // Empty string with spaces is still valid.
+  CheckParser(u"   "_ns, true, 0, parsedFeatures);
+
+  // Non-Existing features with no allowed values
+  CheckParser(u"non-existing-feature"_ns, true, 0, parsedFeatures);
+  CheckParser(u"non-existing-feature;another-feature"_ns, true, 0,
+              parsedFeatures);
+
+  // Existing feature with no allowed values
+  CheckParser(u"camera"_ns, true, 1, parsedFeatures);
+  ASSERT_TRUE(parsedFeatures[0].Name().Equals(u"camera"_ns));
+  ASSERT_TRUE(parsedFeatures[0].HasAllowList());
+
+  // Some spaces.
+  CheckParser(u" camera "_ns, true, 1, parsedFeatures);
+  ASSERT_TRUE(parsedFeatures[0].Name().Equals(u"camera"_ns));
+  ASSERT_TRUE(parsedFeatures[0].HasAllowList());
+
+  // A random ;
+  CheckParser(u"camera;"_ns, true, 1, parsedFeatures);
+  ASSERT_TRUE(parsedFeatures[0].Name().Equals(u"camera"_ns));
+  ASSERT_TRUE(parsedFeatures[0].HasAllowList());
+
+  // Another random ;
+  CheckParser(u";camera;"_ns, true, 1, parsedFeatures);
+  ASSERT_TRUE(parsedFeatures[0].Name().Equals(u"camera"_ns));
+  ASSERT_TRUE(parsedFeatures[0].HasAllowList());
+
+  // 2 features
+  CheckParser(u"camera;microphone"_ns, true, 2, parsedFeatures);
+  ASSERT_TRUE(parsedFeatures[0].Name().Equals(u"camera"_ns));
+  ASSERT_TRUE(parsedFeatures[0].HasAllowList());
+  ASSERT_TRUE(parsedFeatures[1].Name().Equals(u"microphone"_ns));
+  ASSERT_TRUE(parsedFeatures[1].HasAllowList());
+
+  // 2 features with spaces
+  CheckParser(u" camera ; microphone "_ns, true, 2, parsedFeatures);
+  ASSERT_TRUE(parsedFeatures[0].Name().Equals(u"camera"_ns));
+  ASSERT_TRUE(parsedFeatures[0].HasAllowList());
+  ASSERT_TRUE(parsedFeatures[1].Name().Equals(u"microphone"_ns));
+  ASSERT_TRUE(parsedFeatures[1].HasAllowList());
+
+  // 3 features, but only 2 exist.
+  CheckParser(u"camera;microphone;foobar"_ns, true, 2, parsedFeatures);
+  ASSERT_TRUE(parsedFeatures[0].Name().Equals(u"camera"_ns));
+  ASSERT_TRUE(parsedFeatures[0].HasAllowList());
+  ASSERT_TRUE(parsedFeatures[1].Name().Equals(u"microphone"_ns));
+  ASSERT_TRUE(parsedFeatures[1].HasAllowList());
+
+  // Multiple spaces around the value
+  CheckParser(u"camera      'self'"_ns, true, 1, parsedFeatures);
+  ASSERT_TRUE(parsedFeatures[0].Name().Equals(u"camera"_ns));
+  ASSERT_TRUE(parsedFeatures[0].AllowListContains(selfPrincipal));
+
+  // Multiple spaces around the value
+  CheckParser(u"camera      'self'    "_ns, true, 1, parsedFeatures);
+  ASSERT_TRUE(parsedFeatures[0].Name().Equals(u"camera"_ns));
+  ASSERT_TRUE(parsedFeatures[0].AllowListContains(selfPrincipal));
+
+  // No final '
+  CheckParser(u"camera      'self"_ns, true, 1, parsedFeatures);
+  ASSERT_TRUE(parsedFeatures[0].Name().Equals(u"camera"_ns));
+  ASSERT_TRUE(parsedFeatures[0].HasAllowList());
+  ASSERT_TRUE(!parsedFeatures[0].AllowListContains(selfPrincipal));
+
+  // Lowercase/Uppercase
+  CheckParser(u"camera      'selF'"_ns, true, 1, parsedFeatures);
+  ASSERT_TRUE(parsedFeatures[0].Name().Equals(u"camera"_ns));
+  ASSERT_TRUE(parsedFeatures[0].AllowListContains(selfPrincipal));
+
+  // Lowercase/Uppercase
+  CheckParser(u"camera * 'self' none' a.com 123"_ns, true, 1, parsedFeatures);
+  ASSERT_TRUE(parsedFeatures[0].Name().Equals(u"camera"_ns));
+  ASSERT_TRUE(parsedFeatures[0].AllowsAll());
+
+  // After a 'none' we don't continue the parsing.
+  CheckParser(u"camera 'none' a.com b.org c.net d.co.uk"_ns, true, 1,
+              parsedFeatures);
+  ASSERT_TRUE(parsedFeatures[0].Name().Equals(u"camera"_ns));
+  ASSERT_TRUE(parsedFeatures[0].AllowsNone());
+
+  // After a * we don't continue the parsing.
+  CheckParser(u"camera * a.com b.org c.net d.co.uk"_ns, true, 1,
+              parsedFeatures);
+  ASSERT_TRUE(parsedFeatures[0].Name().Equals(u"camera"_ns));
+  ASSERT_TRUE(parsedFeatures[0].AllowsAll());
+
+  // 'self'
+  CheckParser(u"camera 'self'"_ns, true, 1, parsedFeatures);
+  ASSERT_TRUE(parsedFeatures[0].Name().Equals(u"camera"_ns));
+  ASSERT_TRUE(parsedFeatures[0].AllowListContains(selfPrincipal));
+
+  // A couple of URLs
+  CheckParser(u"camera http://example.com http://example.net"_ns, true, 1,
+              parsedFeatures);
+  ASSERT_TRUE(parsedFeatures[0].Name().Equals(u"camera"_ns));
+  ASSERT_TRUE(!parsedFeatures[0].AllowListContains(selfPrincipal));
+  ASSERT_TRUE(parsedFeatures[0].AllowListContains(exampleComPrincipal));
+  ASSERT_TRUE(parsedFeatures[0].AllowListContains(exampleNetPrincipal));
+
+  // A couple of URLs + self
+  CheckParser(u"camera http://example.com 'self' http://example.net"_ns, true,
+              1, parsedFeatures);
+  ASSERT_TRUE(parsedFeatures[0].Name().Equals(u"camera"_ns));
+  ASSERT_TRUE(parsedFeatures[0].AllowListContains(selfPrincipal));
+  ASSERT_TRUE(parsedFeatures[0].AllowListContains(exampleComPrincipal));
+  ASSERT_TRUE(parsedFeatures[0].AllowListContains(exampleNetPrincipal));
+
+  // A couple of URLs but then *
+  CheckParser(u"camera http://example.com 'self' http://example.net *"_ns, true,
+              1, parsedFeatures);
+  ASSERT_TRUE(parsedFeatures[0].Name().Equals(u"camera"_ns));
+  ASSERT_TRUE(parsedFeatures[0].AllowsAll());
+}
diff --git a/dom/security/featurepolicy/test/gtest/moz.build b/dom/security/featurepolicy/test/gtest/moz.build
new file mode 100644
index 0000000000..e307810ff2
--- /dev/null
+++ b/dom/security/featurepolicy/test/gtest/moz.build
@@ -0,0 +1,13 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# 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/.
+
+UNIFIED_SOURCES = [
+    "TestFeaturePolicyParser.cpp",
+]
+
+include("/ipc/chromium/chromium-config.mozbuild")
+
+FINAL_LIBRARY = "xul-gtest"
diff --git a/dom/security/featurepolicy/test/mochitest/empty.html b/dom/security/featurepolicy/test/mochitest/empty.html
new file mode 100644
index 0000000000..64355e7d19
--- /dev/null
+++ b/dom/security/featurepolicy/test/mochitest/empty.html
@@ -0,0 +1 @@
+Nothing here
diff --git a/dom/security/featurepolicy/test/mochitest/mochitest.ini b/dom/security/featurepolicy/test/mochitest/mochitest.ini
new file mode 100644
index 0000000000..3c1850cc2e
--- /dev/null
+++ b/dom/security/featurepolicy/test/mochitest/mochitest.ini
@@ -0,0 +1,11 @@
+[DEFAULT]
+prefs =
+  dom.security.featurePolicy.header.enabled=true
+  dom.security.featurePolicy.webidl.enabled=true
+support-files =
+  empty.html
+  test_parser.html^headers^
+
+[test_parser.html]
+fail-if = xorigin
+[test_featureList.html]
diff --git a/dom/security/featurepolicy/test/mochitest/test_featureList.html b/dom/security/featurepolicy/test/mochitest/test_featureList.html
new file mode 100644
index 0000000000..377c5fccb4
--- /dev/null
+++ b/dom/security/featurepolicy/test/mochitest/test_featureList.html
@@ -0,0 +1,44 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Test feature policy - list</title>
+  <script type="text/javascript" src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<iframe src="empty.html" id="ifr"></iframe>
+<script type="text/javascript">
+
+let supportedFeatures = [
+  "autoplay",
+  "camera",
+  "encrypted-media",
+  "fullscreen",
+  "gamepad",
+  "geolocation",
+  "microphone",
+  "midi",
+  "payment",
+  "display-capture",
+  "document-domain",
+  "speaker-selection",
+  "vr",
+  "web-share",
+];
+
+function checkFeatures(features) {
+  features.forEach(feature => {
+    ok(supportedFeatures.includes(feature), "Feature: " + feature);
+  });
+}
+
+ok("featurePolicy" in document, "We have document.featurePolicy");
+checkFeatures(document.featurePolicy.features());
+
+let ifr = document.getElementById("ifr");
+ok("featurePolicy" in ifr, "We have HTMLIFrameElement.featurePolicy");
+checkFeatures(ifr.featurePolicy.features());
+
+</script>
+</body>
+</html>
diff --git a/dom/security/featurepolicy/test/mochitest/test_parser.html b/dom/security/featurepolicy/test/mochitest/test_parser.html
new file mode 100644
index 0000000000..a8322f6e7d
--- /dev/null
+++ b/dom/security/featurepolicy/test/mochitest/test_parser.html
@@ -0,0 +1,418 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Test feature policy - parsing</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" />
+</head>
+<body>
+<iframe src="empty.html" id="ifr"></iframe>
+<iframe src="https://example.org/tests/dom/security/featurePolicy/test/mochitest/empty.html" id="cross_ifr"></iframe>
+<script type="text/javascript">
+
+SimpleTest.waitForExplicitFinish();
+
+const CROSS_ORIGIN = "https://example.org";
+
+function test_document() {
+  info("Checking document.featurePolicy");
+  ok("featurePolicy" in document, "We have document.featurePolicy");
+
+  ok(!document.featurePolicy.allowsFeature("foobar"), "Random feature");
+  ok(!document.featurePolicy.allowsFeature("foobar", "https://www.something.net"), "Random feature");
+
+  ok(document.featurePolicy.allowsFeature("camera"), "Camera is allowed for self");
+  ok(document.featurePolicy.allowsFeature("camera", "https://foo.bar"), "Camera is always allowed");
+  let allowed = document.featurePolicy.getAllowlistForFeature("camera");
+  is(allowed.length, 1, "Only 1 entry in allowlist for camera");
+  is(allowed[0], "*", "allowlist is *");
+
+  ok(document.featurePolicy.allowsFeature("geolocation"), "Geolocation is allowed for self");
+  ok(document.featurePolicy.allowsFeature("geolocation", location.origin), "Geolocation is allowed for self");
+  ok(!document.featurePolicy.allowsFeature("geolocation", "https://foo.bar"), "Geolocation is not allowed for any random URL");
+  allowed = document.featurePolicy.getAllowlistForFeature("geolocation");
+  is(allowed.length, 1, "Only 1 entry in allowlist for geolocation");
+  is(allowed[0], location.origin, "allowlist is self");
+
+  ok(!document.featurePolicy.allowsFeature("microphone"), "Microphone is disabled for self");
+  ok(!document.featurePolicy.allowsFeature("microphone", location.origin), "Microphone is disabled for self");
+  ok(!document.featurePolicy.allowsFeature("microphone", "https://foo.bar"), "Microphone is disabled for foo.bar");
+  ok(document.featurePolicy.allowsFeature("microphone", "https://example.com"), "Microphone is allowed for example.com");
+  ok(document.featurePolicy.allowsFeature("microphone", "https://example.org"), "Microphone is allowed for example.org");
+  allowed = document.featurePolicy.getAllowlistForFeature("microphone");
+  is(allowed.length, 0, "No allowlist for microphone");
+
+  ok(!document.featurePolicy.allowsFeature("vr"), "Vibrate is disabled for self");
+  ok(!document.featurePolicy.allowsFeature("vr", location.origin), "Vibrate is disabled for self");
+  ok(!document.featurePolicy.allowsFeature("vr", "https://foo.bar"), "Vibrate is disabled for foo.bar");
+  allowed = document.featurePolicy.getAllowlistForFeature("vr");
+  is(allowed.length, 0, "No allowlist for vr");
+
+  allowed = document.featurePolicy.allowedFeatures();
+  // microphone is disabled for this origin, vr is disabled everywhere.
+  let camera = false;
+  let geolocation = false;
+  allowed.forEach(a => {
+    if (a == "camera") camera = true;
+    if (a == "geolocation") geolocation = true;
+  });
+
+  ok(camera, "Camera is always allowed");
+  ok(geolocation, "Geolocation is allowed only for self");
+
+  next();
+}
+
+function test_iframe_without_allow() {
+  info("Checking HTMLIFrameElement.featurePolicy");
+  let ifr = document.getElementById("ifr");
+  ok("featurePolicy" in ifr, "HTMLIFrameElement.featurePolicy exists");
+
+  ok(!ifr.featurePolicy.allowsFeature("foobar"), "Random feature");
+  ok(!ifr.featurePolicy.allowsFeature("foobar", "https://www.something.net"), "Random feature");
+
+  ok(ifr.featurePolicy.allowsFeature("camera"), "Camera is allowed for self");
+  ok(ifr.featurePolicy.allowsFeature("camera", location.origin), "Camera is allowed for self");
+  ok(!ifr.featurePolicy.allowsFeature("camera", "https://foo.bar"), "Camera is not allowed for a random URL");
+  let allowed = ifr.featurePolicy.getAllowlistForFeature("camera");
+  is(allowed.length, 1, "Only 1 entry in allowlist for camera");
+  is(allowed[0], location.origin, "allowlist is 'self'");
+
+  ok(ifr.featurePolicy.allowsFeature("geolocation"), "Geolocation is allowed for self");
+  ok(ifr.featurePolicy.allowsFeature("geolocation", location.origin), "Geolocation is allowed for self");
+  ok(!ifr.featurePolicy.allowsFeature("geolocation", "https://foo.bar"), "Geolocation is not allowed for any random URL");
+  allowed = ifr.featurePolicy.getAllowlistForFeature("geolocation");
+  is(allowed.length, 1, "Only 1 entry in allowlist for geolocation");
+  is(allowed[0], location.origin, "allowlist is '*'");
+
+  ok(!ifr.featurePolicy.allowsFeature("microphone"), "Microphone is disabled for self");
+  ok(!ifr.featurePolicy.allowsFeature("microphone", location.origin), "Microphone is disabled for self");
+  ok(!ifr.featurePolicy.allowsFeature("microphone", "https://foo.bar"), "Microphone is disabled for foo.bar");
+  ok(!ifr.featurePolicy.allowsFeature("microphone", "https://example.com"), "Microphone is disabled for example.com");
+  ok(!ifr.featurePolicy.allowsFeature("microphone", "https://example.org"), "Microphone is disabled for example.org");
+  allowed = ifr.featurePolicy.getAllowlistForFeature("microphone");
+  is(allowed.length, 0, "No allowlist for microphone");
+
+  ok(!ifr.featurePolicy.allowsFeature("vr"), "Vibrate is disabled for self");
+  ok(!ifr.featurePolicy.allowsFeature("vr", location.origin), "Vibrate is disabled for self");
+  ok(!ifr.featurePolicy.allowsFeature("vr", "https://foo.bar"), "Vibrate is disabled for foo.bar");
+  allowed = ifr.featurePolicy.getAllowlistForFeature("vr");
+  is(allowed.length, 0, "No allowlist for vr");
+
+  ok(ifr.featurePolicy.allowedFeatures().includes("camera"), "Camera is allowed");
+  ok(ifr.featurePolicy.allowedFeatures().includes("geolocation"), "Geolocation is allowed");
+  // microphone is disabled for this origin
+  ok(!ifr.featurePolicy.allowedFeatures().includes("microphone"), "microphone is not allowed");
+  // vr is disabled everywhere.
+  ok(!ifr.featurePolicy.allowedFeatures().includes("vr"), "VR is not allowed");
+
+  next();
+}
+
+function test_iframe_with_allow() {
+  info("Checking HTMLIFrameElement.featurePolicy");
+  let ifr = document.getElementById("ifr");
+  ok("featurePolicy" in ifr, "HTMLIFrameElement.featurePolicy exists");
+
+  ifr.setAttribute("allow", "camera 'none'");
+
+  ok(!ifr.featurePolicy.allowsFeature("foobar"), "Random feature");
+  ok(!ifr.featurePolicy.allowsFeature("foobar", "https://www.something.net"), "Random feature");
+
+  ok(!ifr.featurePolicy.allowsFeature("camera"), "Camera is not allowed");
+  let allowed = ifr.featurePolicy.getAllowlistForFeature("camera");
+  is(allowed.length, 0, "Camera has an empty allowlist");
+
+  ok(ifr.featurePolicy.allowsFeature("geolocation"), "Geolocation is allowed for self");
+  ok(ifr.featurePolicy.allowsFeature("geolocation", location.origin), "Geolocation is allowed for self");
+  ok(!ifr.featurePolicy.allowsFeature("geolocation", "https://foo.bar"), "Geolocation is not allowed for any random URL");
+  allowed = ifr.featurePolicy.getAllowlistForFeature("geolocation");
+  is(allowed.length, 1, "Only 1 entry in allowlist for geolocation");
+  is(allowed[0], location.origin, "allowlist is '*'");
+
+  ok(!ifr.featurePolicy.allowsFeature("microphone"), "Microphone is disabled for self");
+  ok(!ifr.featurePolicy.allowsFeature("microphone", location.origin), "Microphone is disabled for self");
+  ok(!ifr.featurePolicy.allowsFeature("microphone", "https://foo.bar"), "Microphone is disabled for foo.bar");
+  ok(!ifr.featurePolicy.allowsFeature("microphone", "https://example.com"), "Microphone is disabled for example.com");
+  ok(!ifr.featurePolicy.allowsFeature("microphone", "https://example.org"), "Microphone is disabled for example.org");
+  allowed = ifr.featurePolicy.getAllowlistForFeature("microphone");
+  is(allowed.length, 0, "No allowlist for microphone");
+
+  ok(!ifr.featurePolicy.allowsFeature("vr"), "Vibrate is disabled for self");
+  ok(!ifr.featurePolicy.allowsFeature("vr", location.origin), "Vibrate is disabled for self");
+  ok(!ifr.featurePolicy.allowsFeature("vr", "https://foo.bar"), "Vibrate is disabled for foo.bar");
+  allowed = ifr.featurePolicy.getAllowlistForFeature("vr");
+  is(allowed.length, 0, "No allowlist for vr");
+
+  ok(ifr.featurePolicy.allowedFeatures().includes("geolocation"), "Geolocation is allowed only for self");
+
+  next();
+}
+
+function test_iframe_contentDocument() {
+  info("Checking iframe document.featurePolicy");
+
+  let ifr = document.createElement("iframe");
+  ifr.setAttribute("src", "empty.html");
+  ifr.onload = function() {
+    ok("featurePolicy" in ifr.contentDocument, "We have ifr.contentDocument.featurePolicy");
+
+    ok(!ifr.contentDocument.featurePolicy.allowsFeature("foobar"), "Random feature");
+    ok(!ifr.contentDocument.featurePolicy.allowsFeature("foobar", "https://www.something.net"), "Random feature");
+
+    ok(ifr.contentDocument.featurePolicy.allowsFeature("camera"), "Camera is allowed for self");
+    ok(ifr.contentDocument.featurePolicy.allowsFeature("camera", location.origin), "Camera is allowed for self");
+    ok(!ifr.contentDocument.featurePolicy.allowsFeature("camera", "https://foo.bar"), "Camera is allowed for self");
+    let allowed = ifr.contentDocument.featurePolicy.getAllowlistForFeature("camera");
+    is(allowed.length, 1, "Only 1 entry in allowlist for camera");
+    is(allowed[0], location.origin, "allowlist is 'self'");
+
+    ok(ifr.featurePolicy.allowsFeature("geolocation"), "Geolocation is allowed for self");
+    ok(ifr.featurePolicy.allowsFeature("geolocation", location.origin), "Geolocation is allowed for self");
+    ok(!ifr.featurePolicy.allowsFeature("geolocation", "https://foo.bar"), "Geolocation is not allowed for any random URL");
+    allowed = ifr.featurePolicy.getAllowlistForFeature("geolocation");
+    is(allowed.length, 1, "Only 1 entry in allowlist for geolocation");
+    is(allowed[0], location.origin, "allowlist is '*'");
+
+    ok(!ifr.contentDocument.featurePolicy.allowsFeature("microphone"), "Microphone is disabled for self");
+    ok(!ifr.contentDocument.featurePolicy.allowsFeature("microphone", location.origin), "Microphone is disabled for self");
+    ok(!ifr.contentDocument.featurePolicy.allowsFeature("microphone", "https://foo.bar"), "Microphone is disabled for foo.bar");
+    ok(!ifr.contentDocument.featurePolicy.allowsFeature("microphone", "https://example.com"), "Microphone is allowed for example.com");
+    ok(!ifr.contentDocument.featurePolicy.allowsFeature("microphone", "https://example.org"), "Microphone is allowed for example.org");
+    allowed = ifr.contentDocument.featurePolicy.getAllowlistForFeature("microphone");
+    is(allowed.length, 0, "No allowlist for microphone");
+
+    ok(!ifr.contentDocument.featurePolicy.allowsFeature("vr"), "Vibrate is disabled for self");
+    ok(!ifr.contentDocument.featurePolicy.allowsFeature("vr", location.origin), "Vibrate is disabled for self");
+    ok(!ifr.contentDocument.featurePolicy.allowsFeature("vr", "https://foo.bar"), "Vibrate is disabled for foo.bar");
+    allowed = ifr.contentDocument.featurePolicy.getAllowlistForFeature("vr");
+    is(allowed.length, 0, "No allowlist for vr");
+
+    ok(ifr.contentDocument.featurePolicy.allowedFeatures().includes("camera"), "Camera is allowed");
+    ok(ifr.contentDocument.featurePolicy.allowedFeatures().includes("geolocation"), "Geolocation is allowed");
+    // microphone is disabled for this origin
+    ok(!ifr.contentDocument.featurePolicy.allowedFeatures().includes("microphone"), "Microphone is not allowed");
+    // vr is disabled everywhere.
+    ok(!ifr.contentDocument.featurePolicy.allowedFeatures().includes("vr"), "VR is not allowed");
+
+    next();
+  };
+  document.body.appendChild(ifr);
+}
+
+function test_cross_iframe_without_allow() {
+  info("Checking cross HTMLIFrameElement.featurePolicy no allow");
+  let ifr = document.getElementById("cross_ifr");
+  ok("featurePolicy" in ifr, "HTMLIFrameElement.featurePolicy exists");
+
+  ok(!ifr.featurePolicy.allowsFeature("foobar"), "Random feature");
+  ok(!ifr.featurePolicy.allowsFeature("foobar", "https://www.something.net"), "Random feature");
+
+  ok(ifr.featurePolicy.allowsFeature("camera"), "Camera is allowed for self");
+  ok(ifr.featurePolicy.allowsFeature("camera", CROSS_ORIGIN), "Camera is allowed for self");
+  ok(!ifr.featurePolicy.allowsFeature("camera", "https://foo.bar"), "Camera is not allowed for a random URL");
+  let allowed = ifr.featurePolicy.getAllowlistForFeature("camera");
+  is(allowed.length, 1, "Only 1 entry in allowlist for camera");
+  is(allowed[0], CROSS_ORIGIN, "allowlist is 'self'");
+
+  ok(!ifr.featurePolicy.allowsFeature("geolocation"), "Geolocation is not allowed for self");
+  ok(!ifr.featurePolicy.allowsFeature("geolocation", CROSS_ORIGIN),
+    "Geolocation is not allowed for self");
+  ok(!ifr.featurePolicy.allowsFeature("geolocation", "https://foo.bar"), "Geolocation is not allowed for any random URL");
+  allowed = ifr.featurePolicy.getAllowlistForFeature("geolocation");
+  is(allowed.length, 0, "No allowlist for geolocation");
+
+  ok(ifr.featurePolicy.allowsFeature("microphone"), "Microphone is enabled for self");
+  ok(ifr.featurePolicy.allowsFeature("microphone", CROSS_ORIGIN), "Microphone is enabled for self");
+  ok(!ifr.featurePolicy.allowsFeature("microphone", "https://foo.bar"), "Microphone is disabled for foo.bar");
+  ok(!ifr.featurePolicy.allowsFeature("microphone", "https://example.com"), "Microphone is disabled for example.com");
+  allowed = ifr.featurePolicy.getAllowlistForFeature("microphone");
+  is(allowed.length, 1, "Only 1 entry in allowlist for microphone");
+  is(allowed[0], CROSS_ORIGIN, "allowlist is self");
+
+  ok(!ifr.featurePolicy.allowsFeature("vr"), "Vibrate is disabled for self");
+  ok(!ifr.featurePolicy.allowsFeature("vr", CROSS_ORIGIN), "Vibrate is disabled for self");
+  ok(!ifr.featurePolicy.allowsFeature("vr", "https://foo.bar"), "Vibrate is disabled for foo.bar");
+  allowed = ifr.featurePolicy.getAllowlistForFeature("vr");
+  is(allowed.length, 0, "No allowlist for vr");
+
+  ok(ifr.featurePolicy.allowedFeatures().includes("camera"), "Camera is allowed");
+  ok(!ifr.featurePolicy.allowedFeatures().includes("geolocation"), "Geolocation is not allowed");
+  // microphone is enabled for this origin
+  ok(ifr.featurePolicy.allowedFeatures().includes("microphone"), "microphone is allowed");
+  // vr is disabled everywhere.
+  ok(!ifr.featurePolicy.allowedFeatures().includes("vr"), "VR is not allowed");
+
+  next();
+}
+
+function test_cross_iframe_with_allow() {
+  info("Checking cross HTMLIFrameElement.featurePolicy with allow");
+  let ifr = document.getElementById("cross_ifr");
+  ok("featurePolicy" in ifr, "HTMLIFrameElement.featurePolicy exists");
+
+  ifr.setAttribute("allow", "geolocation; camera 'none'");
+
+  ok(!ifr.featurePolicy.allowsFeature("foobar"), "Random feature");
+  ok(!ifr.featurePolicy.allowsFeature("foobar", "https://www.something.net"), "Random feature");
+
+  ok(!ifr.featurePolicy.allowsFeature("camera"), "Camera is not allowed");
+  let allowed = ifr.featurePolicy.getAllowlistForFeature("camera");
+  is(allowed.length, 0, "Camera has an empty allowlist");
+
+  ok(ifr.featurePolicy.allowsFeature("geolocation"), "Geolocation is allowed for self");
+  ok(ifr.featurePolicy.allowsFeature("geolocation", CROSS_ORIGIN), "Geolocation is allowed for self");
+  ok(!ifr.featurePolicy.allowsFeature("geolocation", "https://foo.bar"), "Geolocation is not allowed for any random URL");
+  allowed = ifr.featurePolicy.getAllowlistForFeature("geolocation");
+  is(allowed.length, 1, "Only 1 entry in allowlist for geolocation");
+  is(allowed[0], CROSS_ORIGIN, "allowlist is '*'");
+
+  ok(ifr.featurePolicy.allowsFeature("microphone"), "Microphone is enabled for self");
+  ok(ifr.featurePolicy.allowsFeature("microphone", CROSS_ORIGIN), "Microphone is enabled for self");
+  ok(!ifr.featurePolicy.allowsFeature("microphone", "https://foo.bar"), "Microphone is disabled for foo.bar");
+  ok(!ifr.featurePolicy.allowsFeature("microphone", "https://example.com"), "Microphone is disabled for example.com");
+  allowed = ifr.featurePolicy.getAllowlistForFeature("microphone");
+  is(allowed.length, 1, "Only 1 entry in allowlist for microphone");
+  is(allowed[0], CROSS_ORIGIN, "allowlist is self");
+
+  ok(!ifr.featurePolicy.allowsFeature("vr"), "Vibrate is disabled for self");
+  ok(!ifr.featurePolicy.allowsFeature("vr", CROSS_ORIGIN), "Vibrate is disabled for self");
+  ok(!ifr.featurePolicy.allowsFeature("vr", "https://foo.bar"), "Vibrate is disabled for foo.bar");
+  allowed = ifr.featurePolicy.getAllowlistForFeature("vr");
+  is(allowed.length, 0, "No allowlist for vr");
+
+  ok(ifr.featurePolicy.allowedFeatures().includes("geolocation"), "Geolocation is allowed only for self");
+  // microphone is enabled for this origin
+  ok(ifr.featurePolicy.allowedFeatures().includes("microphone"), "microphone is allowed");
+
+  next();
+}
+
+function test_cross_iframe_contentDocument_no_allow() {
+  info("Checking cross iframe document.featurePolicy no allow");
+
+  let ifr = document.createElement("iframe");
+  ifr.setAttribute("src", "https://example.org/tests/dom/security/featurePolicy/test/mochitest/empty.html");
+  ifr.onload = async function() {
+    await SpecialPowers.spawn(ifr, [], () => {
+      Assert.ok("featurePolicy" in this.content.document, "We have this.content.document.featurePolicy");
+
+      Assert.ok(!this.content.document.featurePolicy.allowsFeature("foobar"), "Random feature");
+      Assert.ok(!this.content.document.featurePolicy.allowsFeature("foobar", "https://www.something.net"), "Random feature");
+
+      Assert.ok(this.content.document.featurePolicy.allowsFeature("camera"), "Camera is allowed for self");
+      Assert.ok(this.content.document.featurePolicy.allowsFeature("camera", "https://example.org"), "Camera is allowed for self");
+      Assert.ok(!this.content.document.featurePolicy.allowsFeature("camera", "https://foo.bar"), "Camera is not allowed for a random URL");
+      let allowed = this.content.document.featurePolicy.getAllowlistForFeature("camera");
+      Assert.equal(allowed.length, 1, "Only 1 entry in allowlist for camera");
+      Assert.equal(allowed[0], "https://example.org", "allowlist is 'self'");
+
+      Assert.ok(!this.content.document.featurePolicy.allowsFeature("geolocation"), "Geolocation is not allowed for self");
+      Assert.ok(!this.content.document.featurePolicy.allowsFeature("geolocation", "https://example.org"),
+        "Geolocation is not allowed for self");
+      Assert.ok(!this.content.document.featurePolicy.allowsFeature("geolocation", "https://foo.bar"), "Geolocation is not allowed for any random URL");
+      allowed = this.content.document.featurePolicy.getAllowlistForFeature("geolocation");
+      Assert.equal(allowed.length, 0, "No allowlist for geolocation");
+
+      Assert.ok(this.content.document.featurePolicy.allowsFeature("microphone"), "Microphone is enabled for self");
+      Assert.ok(this.content.document.featurePolicy.allowsFeature("microphone", "https://example.org"), "Microphone is enabled for self");
+      Assert.ok(!this.content.document.featurePolicy.allowsFeature("microphone", "https://foo.bar"), "Microphone is disabled for foo.bar");
+      Assert.ok(!this.content.document.featurePolicy.allowsFeature("microphone", "https://example.com"), "Microphone is disabled for example.com");
+      allowed = this.content.document.featurePolicy.getAllowlistForFeature("microphone");
+      Assert.equal(allowed.length, 1, "Only 1 entry in allowlist for microphone");
+      Assert.equal(allowed[0], "https://example.org", "allowlist is self");
+
+      Assert.ok(!this.content.document.featurePolicy.allowsFeature("vr"), "Vibrate is disabled for self");
+      Assert.ok(!this.content.document.featurePolicy.allowsFeature("vr", "https://example.org"), "Vibrate is disabled for self");
+      Assert.ok(!this.content.document.featurePolicy.allowsFeature("vr", "https://foo.bar"), "Vibrate is disabled for foo.bar");
+      allowed = this.content.document.featurePolicy.getAllowlistForFeature("vr");
+      Assert.equal(allowed.length, 0, "No allowlist for vr");
+
+      Assert.ok(this.content.document.featurePolicy.allowedFeatures().includes("camera"), "Camera is allowed");
+      Assert.ok(!this.content.document.featurePolicy.allowedFeatures().includes("geolocation"), "Geolocation is not allowed");
+      // microphone is enabled for this origin
+      Assert.ok(this.content.document.featurePolicy.allowedFeatures().includes("microphone"), "microphone is allowed");
+      // vr is disabled everywhere.
+      Assert.ok(!this.content.document.featurePolicy.allowedFeatures().includes("vr"), "VR is not allowed");
+    });
+
+    next();
+  };
+  document.body.appendChild(ifr);
+}
+
+function test_cross_iframe_contentDocument_allow() {
+  info("Checking cross iframe document.featurePolicy with allow");
+
+  let ifr = document.createElement("iframe");
+  ifr.setAttribute("src", "https://example.org/tests/dom/security/featurePolicy/test/mochitest/empty.html");
+  ifr.setAttribute("allow", "geolocation; camera 'none'");
+  ifr.onload = async function() {
+    await SpecialPowers.spawn(ifr, [], () => {
+      Assert.ok("featurePolicy" in this.content.document, "We have this.content.document.featurePolicy");
+
+      Assert.ok(!this.content.document.featurePolicy.allowsFeature("foobar"), "Random feature");
+      Assert.ok(!this.content.document.featurePolicy.allowsFeature("foobar", "https://www.something.net"), "Random feature");
+
+      Assert.ok(!this.content.document.featurePolicy.allowsFeature("camera"), "Camera is not allowed");
+      let allowed = this.content.document.featurePolicy.getAllowlistForFeature("camera");
+      Assert.equal(allowed.length, 0, "Camera has an empty allowlist");
+
+      Assert.ok(this.content.document.featurePolicy.allowsFeature("geolocation"), "Geolocation is allowed for self");
+      Assert.ok(this.content.document.featurePolicy.allowsFeature("geolocation", "https://example.org"), "Geolocation is allowed for self");
+      Assert.ok(!this.content.document.featurePolicy.allowsFeature("geolocation", "https://foo.bar"), "Geolocation is not allowed for any random URL");
+      allowed = this.content.document.featurePolicy.getAllowlistForFeature("geolocation");
+      Assert.equal(allowed.length, 1, "Only 1 entry in allowlist for geolocation");
+      Assert.equal(allowed[0], "https://example.org", "allowlist is '*'");
+
+      Assert.ok(this.content.document.featurePolicy.allowsFeature("microphone"), "Microphone is enabled for self");
+      Assert.ok(this.content.document.featurePolicy.allowsFeature("microphone", "https://example.org"), "Microphone is enabled for self");
+      Assert.ok(!this.content.document.featurePolicy.allowsFeature("microphone", "https://foo.bar"), "Microphone is disabled for foo.bar");
+      Assert.ok(!this.content.document.featurePolicy.allowsFeature("microphone", "https://example.com"), "Microphone is disabled for example.com");
+      allowed = this.content.document.featurePolicy.getAllowlistForFeature("microphone");
+      Assert.equal(allowed.length, 1, "Only 1 entry in allowlist for microphone");
+      Assert.equal(allowed[0], "https://example.org", "allowlist is self");
+
+      Assert.ok(!this.content.document.featurePolicy.allowsFeature("vr"), "Vibrate is disabled for self");
+      Assert.ok(!this.content.document.featurePolicy.allowsFeature("vr", "https://example.org"), "Vibrate is disabled for self");
+      Assert.ok(!this.content.document.featurePolicy.allowsFeature("vr", "https://foo.bar"), "Vibrate is disabled for foo.bar");
+      allowed = this.content.document.featurePolicy.getAllowlistForFeature("vr");
+      Assert.equal(allowed.length, 0, "No allowlist for vr");
+
+      Assert.ok(this.content.document.featurePolicy.allowedFeatures().includes("geolocation"), "Geolocation is allowed only for self");
+      // microphone is enabled for this origin
+      Assert.ok(this.content.document.featurePolicy.allowedFeatures().includes("microphone"), "microphone is allowed");
+    });
+
+    next();
+  };
+  document.body.appendChild(ifr);
+}
+
+
+var tests = [
+  test_document,
+  test_iframe_without_allow,
+  test_iframe_with_allow,
+  test_iframe_contentDocument,
+  test_cross_iframe_without_allow,
+  test_cross_iframe_with_allow,
+  test_cross_iframe_contentDocument_no_allow,
+  test_cross_iframe_contentDocument_allow
+];
+
+function next() {
+  if (!tests.length) {
+    SimpleTest.finish();
+    return;
+  }
+
+  var test = tests.shift();
+  test();
+}
+
+next();
+
+</script>
+</body>
+</html>
diff --git a/dom/security/featurepolicy/test/mochitest/test_parser.html^headers^ b/dom/security/featurepolicy/test/mochitest/test_parser.html^headers^
new file mode 100644
index 0000000000..949de013d3
--- /dev/null
+++ b/dom/security/featurepolicy/test/mochitest/test_parser.html^headers^
@@ -0,0 +1 @@
+Feature-Policy: camera *; geolocation 'self'; microphone https://example.com https://example.org; vr 'none'
-- 
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