gecko-dev/caps/BasePrincipal.h
2019-02-11 18:03:12 +00:00

359 lines
13 KiB
C++

/* -*- 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_BasePrincipal_h
#define mozilla_BasePrincipal_h
#include "nsJSPrincipals.h"
#include "mozilla/Attributes.h"
#include "mozilla/OriginAttributes.h"
class nsAtom;
class nsIContentSecurityPolicy;
class nsIObjectOutputStream;
class nsIObjectInputStream;
class nsIURI;
class ExpandedPrincipal;
namespace mozilla {
namespace dom {
class Document;
}
namespace extensions {
class WebExtensionPolicy;
}
class BasePrincipal;
// Codebase principals (and codebase principals embedded within expanded
// principals) stored in SiteIdentifier are guaranteed to contain only the
// eTLD+1 part of the original domain. This is used to determine whether two
// origins are same-site: if it's possible for two origins to access each other
// (maybe after mutating document.domain), then they must have the same site
// identifier.
class SiteIdentifier {
public:
void Init(BasePrincipal* aPrincipal) {
MOZ_ASSERT(aPrincipal);
mPrincipal = aPrincipal;
}
bool IsInitialized() const { return !!mPrincipal; }
bool Equals(const SiteIdentifier& aOther) const;
private:
friend class ::ExpandedPrincipal;
BasePrincipal* GetPrincipal() const {
MOZ_ASSERT(IsInitialized());
return mPrincipal;
}
RefPtr<BasePrincipal> mPrincipal;
};
/*
* Base class from which all nsIPrincipal implementations inherit. Use this for
* default implementations and other commonalities between principal
* implementations.
*
* We should merge nsJSPrincipals into this class at some point.
*/
class BasePrincipal : public nsJSPrincipals {
public:
enum PrincipalKind {
eNullPrincipal,
eCodebasePrincipal,
eExpandedPrincipal,
eSystemPrincipal
};
explicit BasePrincipal(PrincipalKind aKind);
template <typename T>
bool Is() const {
return mKind == T::Kind();
}
template <typename T>
T* As() {
MOZ_ASSERT(Is<T>());
return static_cast<T*>(this);
}
enum DocumentDomainConsideration {
DontConsiderDocumentDomain,
ConsiderDocumentDomain
};
bool Subsumes(nsIPrincipal* aOther,
DocumentDomainConsideration aConsideration);
NS_IMETHOD GetOrigin(nsACString& aOrigin) final;
NS_IMETHOD GetOriginNoSuffix(nsACString& aOrigin) final;
NS_IMETHOD Equals(nsIPrincipal* other, bool* _retval) final;
NS_IMETHOD EqualsConsideringDomain(nsIPrincipal* other, bool* _retval) final;
NS_IMETHOD Subsumes(nsIPrincipal* other, bool* _retval) final;
NS_IMETHOD SubsumesConsideringDomain(nsIPrincipal* other,
bool* _retval) final;
NS_IMETHOD SubsumesConsideringDomainIgnoringFPD(nsIPrincipal* other,
bool* _retval) final;
NS_IMETHOD CheckMayLoad(nsIURI* uri, bool report,
bool allowIfInheritsPrincipal) final;
NS_IMETHOD GetAddonPolicy(nsISupports** aResult) final;
NS_IMETHOD GetCsp(nsIContentSecurityPolicy** aCsp) override;
NS_IMETHOD SetCsp(nsIContentSecurityPolicy* aCsp) override;
NS_IMETHOD EnsureCSP(dom::Document* aDocument,
nsIContentSecurityPolicy** aCSP) override;
NS_IMETHOD GetPreloadCsp(nsIContentSecurityPolicy** aPreloadCSP) override;
NS_IMETHOD EnsurePreloadCSP(dom::Document* aDocument,
nsIContentSecurityPolicy** aCSP) override;
NS_IMETHOD GetCspJSON(nsAString& outCSPinJSON) override;
NS_IMETHOD GetIsNullPrincipal(bool* aResult) override;
NS_IMETHOD GetIsCodebasePrincipal(bool* aResult) override;
NS_IMETHOD GetIsExpandedPrincipal(bool* aResult) override;
NS_IMETHOD GetIsSystemPrincipal(bool* aResult) override;
NS_IMETHOD GetIsAddonOrExpandedAddonPrincipal(bool* aResult) override;
NS_IMETHOD GetOriginAttributes(JSContext* aCx,
JS::MutableHandle<JS::Value> aVal) final;
NS_IMETHOD GetOriginSuffix(nsACString& aOriginSuffix) final;
NS_IMETHOD GetAppId(uint32_t* aAppId) final;
NS_IMETHOD GetIsInIsolatedMozBrowserElement(
bool* aIsInIsolatedMozBrowserElement) final;
NS_IMETHOD GetUserContextId(uint32_t* aUserContextId) final;
NS_IMETHOD GetPrivateBrowsingId(uint32_t* aPrivateBrowsingId) final;
NS_IMETHOD GetSiteOrigin(nsACString& aOrigin) override;
virtual bool AddonHasPermission(const nsAtom* aPerm);
virtual bool IsCodebasePrincipal() const { return false; };
static BasePrincipal* Cast(nsIPrincipal* aPrin) {
return static_cast<BasePrincipal*>(aPrin);
}
static const BasePrincipal* Cast(const nsIPrincipal* aPrin) {
return static_cast<const BasePrincipal*>(aPrin);
}
static already_AddRefed<BasePrincipal> CreateCodebasePrincipal(
const nsACString& aOrigin);
// These following method may not create a codebase principal in case it's
// not possible to generate a correct origin from the passed URI. If this
// happens, a NullPrincipal is returned.
static already_AddRefed<BasePrincipal> CreateCodebasePrincipal(
nsIURI* aURI, const OriginAttributes& aAttrs);
const OriginAttributes& OriginAttributesRef() final {
return mOriginAttributes;
}
uint32_t AppId() const { return mOriginAttributes.mAppId; }
extensions::WebExtensionPolicy* AddonPolicy();
uint32_t UserContextId() const { return mOriginAttributes.mUserContextId; }
uint32_t PrivateBrowsingId() const {
return mOriginAttributes.mPrivateBrowsingId;
}
bool IsInIsolatedMozBrowserElement() const {
return mOriginAttributes.mInIsolatedMozBrowser;
}
PrincipalKind Kind() const { return mKind; }
already_AddRefed<BasePrincipal>
CloneStrippingUserContextIdAndFirstPartyDomain();
// If this is an add-on content script principal, returns its AddonPolicy.
// Otherwise returns null.
extensions::WebExtensionPolicy* ContentScriptAddonPolicy();
// Helper to check whether this principal is associated with an addon that
// allows unprivileged code to load aURI. aExplicit == true will prevent
// use of all_urls permission, requiring the domain in its permissions.
bool AddonAllowsLoad(nsIURI* aURI, bool aExplicit = false);
// Call these to avoid the cost of virtual dispatch.
inline bool FastEquals(nsIPrincipal* aOther);
inline bool FastEqualsConsideringDomain(nsIPrincipal* aOther);
inline bool FastSubsumes(nsIPrincipal* aOther);
inline bool FastSubsumesConsideringDomain(nsIPrincipal* aOther);
inline bool FastSubsumesIgnoringFPD(nsIPrincipal* aOther);
inline bool FastSubsumesConsideringDomainIgnoringFPD(nsIPrincipal* aOther);
// Fast way to check whether we have a system principal.
inline bool IsSystemPrincipal() const;
// Returns the principal to inherit when a caller with this principal loads
// the given URI.
//
// For most principal types, this returns the principal itself. For expanded
// principals, it returns the first sub-principal which subsumes the given URI
// (or, if no URI is given, the last allowlist principal).
nsIPrincipal* PrincipalToInherit(nsIURI* aRequestedURI = nullptr);
/**
* Returns true if this principal's CSP should override a document's CSP for
* loads that it triggers. Currently true for system principal, for expanded
* principals which subsume the document principal, and add-on codebase
* principals regardless of whether they subsume the document principal.
*/
bool OverridesCSP(nsIPrincipal* aDocumentPrincipal) {
// SystemPrincipal can override the page's CSP by definition.
if (mKind == eSystemPrincipal) {
return true;
}
// Expanded principals override CSP if and only if they subsume the document
// principal.
if (mKind == eExpandedPrincipal) {
return FastSubsumes(aDocumentPrincipal);
}
// Extension principals always override the CSP non-extension principals.
// This is primarily for the sake of their stylesheets, which are usually
// loaded from channels and cannot have expanded principals.
return (AddonPolicy() &&
!BasePrincipal::Cast(aDocumentPrincipal)->AddonPolicy());
}
uint32_t GetOriginNoSuffixHash() const { return mOriginNoSuffix->hash(); }
virtual nsresult GetSiteIdentifier(SiteIdentifier& aSite) = 0;
protected:
virtual ~BasePrincipal();
// Note that this does not check OriginAttributes. Callers that depend on
// those must call Subsumes instead.
virtual bool SubsumesInternal(nsIPrincipal* aOther,
DocumentDomainConsideration aConsider) = 0;
// Internal, side-effect-free check to determine whether the concrete
// principal would allow the load ignoring any common behavior implemented in
// BasePrincipal::CheckMayLoad.
virtual bool MayLoadInternal(nsIURI* aURI) = 0;
friend class ::ExpandedPrincipal;
void SetHasExplicitDomain() { mHasExplicitDomain = true; }
// Either of these functions should be called as the last step of the
// initialization of the principal objects. It's typically called as the
// last step from the Init() method of the child classes.
void FinishInit(const nsACString& aOriginNoSuffix,
const OriginAttributes& aOriginAttributes);
void FinishInit(BasePrincipal* aOther,
const OriginAttributes& aOriginAttributes);
nsCOMPtr<nsIContentSecurityPolicy> mCSP;
nsCOMPtr<nsIContentSecurityPolicy> mPreloadCSP;
private:
static already_AddRefed<BasePrincipal> CreateCodebasePrincipal(
nsIURI* aURI, const OriginAttributes& aAttrs,
const nsACString& aOriginNoSuffix);
inline bool FastSubsumesIgnoringFPD(
nsIPrincipal* aOther, DocumentDomainConsideration aConsideration);
RefPtr<nsAtom> mOriginNoSuffix;
RefPtr<nsAtom> mOriginSuffix;
OriginAttributes mOriginAttributes;
PrincipalKind mKind;
bool mHasExplicitDomain;
bool mInitialized;
};
inline bool BasePrincipal::FastEquals(nsIPrincipal* aOther) {
auto other = Cast(aOther);
if (Kind() != other->Kind()) {
// Principals of different kinds can't be equal.
return false;
}
// Two principals are considered to be equal if their origins are the same.
// If the two principals are codebase principals, their origin attributes
// (aka the origin suffix) must also match.
if (Kind() == eSystemPrincipal) {
return this == other;
}
if (Kind() == eCodebasePrincipal || Kind() == eNullPrincipal) {
return mOriginNoSuffix == other->mOriginNoSuffix &&
mOriginSuffix == other->mOriginSuffix;
}
MOZ_ASSERT(Kind() == eExpandedPrincipal);
return mOriginNoSuffix == other->mOriginNoSuffix;
}
inline bool BasePrincipal::FastEqualsConsideringDomain(nsIPrincipal* aOther) {
// If neither of the principals have document.domain set, we use the fast path
// in Equals(). Otherwise, we fall back to the slow path below.
auto other = Cast(aOther);
if (!mHasExplicitDomain && !other->mHasExplicitDomain) {
return FastEquals(aOther);
}
return Subsumes(aOther, ConsiderDocumentDomain) &&
other->Subsumes(this, ConsiderDocumentDomain);
}
inline bool BasePrincipal::FastSubsumes(nsIPrincipal* aOther) {
// If two principals are equal, then they both subsume each other.
if (FastEquals(aOther)) {
return true;
}
// Otherwise, fall back to the slow path.
return Subsumes(aOther, DontConsiderDocumentDomain);
}
inline bool BasePrincipal::FastSubsumesConsideringDomain(nsIPrincipal* aOther) {
// If neither of the principals have document.domain set, we hand off to
// FastSubsumes() which has fast paths for some special cases. Otherwise, we
// fall back to the slow path below.
if (!mHasExplicitDomain && !Cast(aOther)->mHasExplicitDomain) {
return FastSubsumes(aOther);
}
return Subsumes(aOther, ConsiderDocumentDomain);
}
inline bool BasePrincipal::FastSubsumesIgnoringFPD(
nsIPrincipal* aOther, DocumentDomainConsideration aConsideration) {
if (Kind() == eCodebasePrincipal &&
!dom::ChromeUtils::IsOriginAttributesEqualIgnoringFPD(
mOriginAttributes, Cast(aOther)->mOriginAttributes)) {
return false;
}
return SubsumesInternal(aOther, aConsideration);
}
inline bool BasePrincipal::FastSubsumesIgnoringFPD(nsIPrincipal* aOther) {
return FastSubsumesIgnoringFPD(aOther, DontConsiderDocumentDomain);
}
inline bool BasePrincipal::FastSubsumesConsideringDomainIgnoringFPD(
nsIPrincipal* aOther) {
return FastSubsumesIgnoringFPD(aOther, ConsiderDocumentDomain);
}
inline bool BasePrincipal::IsSystemPrincipal() const {
return Kind() == eSystemPrincipal;
}
} // namespace mozilla
inline bool nsIPrincipal::IsSystemPrincipal() const {
return mozilla::BasePrincipal::Cast(this)->IsSystemPrincipal();
}
#endif /* mozilla_BasePrincipal_h */