gecko/js/xpconnect/wrappers/XrayWrapper.h
2014-09-15 16:52:11 +02:00

539 lines
24 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* vim: set ts=8 sts=4 et sw=4 tw=99: */
/* 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 XrayWrapper_h
#define XrayWrapper_h
#include "mozilla/Attributes.h"
#include "WrapperFactory.h"
#include "jswrapper.h"
// Xray wrappers re-resolve the original native properties on the native
// object and always directly access to those properties.
// Because they work so differently from the rest of the wrapper hierarchy,
// we pull them out of the Wrapper inheritance hierarchy and create a
// little world around them.
class nsIPrincipal;
class XPCWrappedNative;
namespace xpc {
namespace XrayUtils {
bool IsXPCWNHolderClass(const JSClass *clasp);
bool CloneExpandoChain(JSContext *cx, JSObject *src, JSObject *dst);
bool
IsTransparent(JSContext *cx, JS::HandleObject wrapper, JS::HandleId id);
JSObject *
GetNativePropertiesObject(JSContext *cx, JSObject *wrapper);
bool
HasNativeProperty(JSContext *cx, JS::HandleObject wrapper, JS::HandleId id,
bool *hasProp);
}
enum XrayType {
XrayForDOMObject,
XrayForWrappedNative,
XrayForJSObject,
XrayForOpaqueObject,
NotXray
};
class XrayTraits
{
public:
XrayTraits() {}
static JSObject* getTargetObject(JSObject *wrapper) {
return js::UncheckedUnwrap(wrapper, /* stopAtOuter = */ false);
}
virtual bool resolveNativeProperty(JSContext *cx, JS::HandleObject wrapper,
JS::HandleObject holder, JS::HandleId id,
JS::MutableHandle<JSPropertyDescriptor> desc) = 0;
// NB: resolveOwnProperty may decide whether or not to cache what it finds
// on the holder. If the result is not cached, the lookup will happen afresh
// for each access, which is the right thing for things like dynamic NodeList
// properties.
virtual bool resolveOwnProperty(JSContext *cx, const js::Wrapper &jsWrapper,
JS::HandleObject wrapper, JS::HandleObject holder,
JS::HandleId id, JS::MutableHandle<JSPropertyDescriptor> desc);
bool delete_(JSContext *cx, JS::HandleObject wrapper, JS::HandleId id, bool *bp) {
*bp = true;
return true;
}
static const char *className(JSContext *cx, JS::HandleObject wrapper, const js::Wrapper& baseInstance) {
return baseInstance.className(cx, wrapper);
}
virtual void preserveWrapper(JSObject *target) = 0;
JSObject* getExpandoObject(JSContext *cx, JS::HandleObject target,
JS::HandleObject consumer);
JSObject* ensureExpandoObject(JSContext *cx, JS::HandleObject wrapper,
JS::HandleObject target);
JSObject* getHolder(JSObject *wrapper);
JSObject* ensureHolder(JSContext *cx, JS::HandleObject wrapper);
virtual JSObject* createHolder(JSContext *cx, JSObject *wrapper) = 0;
JSObject* getExpandoChain(JS::HandleObject obj);
bool setExpandoChain(JSContext *cx, JS::HandleObject obj, JS::HandleObject chain);
bool cloneExpandoChain(JSContext *cx, JS::HandleObject dst, JS::HandleObject src);
private:
bool expandoObjectMatchesConsumer(JSContext *cx, JS::HandleObject expandoObject,
nsIPrincipal *consumerOrigin,
JS::HandleObject exclusiveGlobal);
JSObject* getExpandoObjectInternal(JSContext *cx, JS::HandleObject target,
nsIPrincipal *origin,
JSObject *exclusiveGlobal);
JSObject* attachExpandoObject(JSContext *cx, JS::HandleObject target,
nsIPrincipal *origin,
JS::HandleObject exclusiveGlobal);
XrayTraits(XrayTraits &) MOZ_DELETE;
const XrayTraits& operator=(XrayTraits &) MOZ_DELETE;
};
class XPCWrappedNativeXrayTraits : public XrayTraits
{
public:
enum {
HasPrototype = 0
};
static const XrayType Type = XrayForWrappedNative;
virtual bool resolveNativeProperty(JSContext *cx, JS::HandleObject wrapper,
JS::HandleObject holder, JS::HandleId id,
JS::MutableHandle<JSPropertyDescriptor> desc) MOZ_OVERRIDE;
virtual bool resolveOwnProperty(JSContext *cx, const js::Wrapper &jsWrapper, JS::HandleObject wrapper,
JS::HandleObject holder, JS::HandleId id,
JS::MutableHandle<JSPropertyDescriptor> desc) MOZ_OVERRIDE;
bool defineProperty(JSContext *cx, JS::HandleObject wrapper, JS::HandleId id,
JS::MutableHandle<JSPropertyDescriptor> desc,
JS::Handle<JSPropertyDescriptor> existingDesc, bool *defined);
virtual bool enumerateNames(JSContext *cx, JS::HandleObject wrapper, unsigned flags,
JS::AutoIdVector &props);
static bool call(JSContext *cx, JS::HandleObject wrapper,
const JS::CallArgs &args, const js::Wrapper& baseInstance);
static bool construct(JSContext *cx, JS::HandleObject wrapper,
const JS::CallArgs &args, const js::Wrapper& baseInstance);
static bool resolveDOMCollectionProperty(JSContext *cx, JS::HandleObject wrapper,
JS::HandleObject holder, JS::HandleId id,
JS::MutableHandle<JSPropertyDescriptor> desc);
static XPCWrappedNative* getWN(JSObject *wrapper);
virtual void preserveWrapper(JSObject *target) MOZ_OVERRIDE;
virtual JSObject* createHolder(JSContext *cx, JSObject *wrapper) MOZ_OVERRIDE;
static const JSClass HolderClass;
static XPCWrappedNativeXrayTraits singleton;
};
class DOMXrayTraits : public XrayTraits
{
public:
enum {
HasPrototype = 1
};
static const XrayType Type = XrayForDOMObject;
virtual bool resolveNativeProperty(JSContext *cx, JS::HandleObject wrapper,
JS::HandleObject holder, JS::HandleId id,
JS::MutableHandle<JSPropertyDescriptor> desc) MOZ_OVERRIDE
{
// Xrays for DOM binding objects have a prototype chain that consists of
// Xrays for the prototypes of the DOM binding object (ignoring changes
// in the prototype chain made by script, plugins or XBL). All properties for
// these Xrays are really own properties, either of the instance object or
// of the prototypes.
// FIXME https://bugzilla.mozilla.org/show_bug.cgi?id=1072482
// This should really be:
// MOZ_CRASH("resolveNativeProperty hook should never be called with HasPrototype = 1");
// but we can't do that yet because XrayUtils::HasNativeProperty calls this.
return true;
}
virtual bool resolveOwnProperty(JSContext *cx, const js::Wrapper &jsWrapper, JS::HandleObject wrapper,
JS::HandleObject holder, JS::HandleId id,
JS::MutableHandle<JSPropertyDescriptor> desc) MOZ_OVERRIDE;
bool defineProperty(JSContext *cx, JS::HandleObject wrapper, JS::HandleId id,
JS::MutableHandle<JSPropertyDescriptor> desc,
JS::Handle<JSPropertyDescriptor> existingDesc, bool *defined);
virtual bool enumerateNames(JSContext *cx, JS::HandleObject wrapper, unsigned flags,
JS::AutoIdVector &props);
static bool call(JSContext *cx, JS::HandleObject wrapper,
const JS::CallArgs &args, const js::Wrapper& baseInstance);
static bool construct(JSContext *cx, JS::HandleObject wrapper,
const JS::CallArgs &args, const js::Wrapper& baseInstance);
static bool getPrototypeOf(JSContext *cx, JS::HandleObject wrapper,
JS::HandleObject target,
JS::MutableHandleObject protop);
virtual void preserveWrapper(JSObject *target) MOZ_OVERRIDE;
virtual JSObject* createHolder(JSContext *cx, JSObject *wrapper) MOZ_OVERRIDE;
static DOMXrayTraits singleton;
};
class JSXrayTraits : public XrayTraits
{
public:
enum {
HasPrototype = 1
};
static const XrayType Type = XrayForJSObject;
virtual bool resolveNativeProperty(JSContext *cx, JS::HandleObject wrapper,
JS::HandleObject holder, JS::HandleId id,
JS::MutableHandle<JSPropertyDescriptor> desc) MOZ_OVERRIDE
{
MOZ_CRASH("resolveNativeProperty hook should never be called with HasPrototype = 1");
}
virtual bool resolveOwnProperty(JSContext *cx, const js::Wrapper &jsWrapper, JS::HandleObject wrapper,
JS::HandleObject holder, JS::HandleId id,
JS::MutableHandle<JSPropertyDescriptor> desc) MOZ_OVERRIDE;
bool delete_(JSContext *cx, JS::HandleObject wrapper, JS::HandleId id, bool *bp);
bool defineProperty(JSContext *cx, JS::HandleObject wrapper, JS::HandleId id,
JS::MutableHandle<JSPropertyDescriptor> desc,
JS::Handle<JSPropertyDescriptor> existingDesc, bool *defined);
virtual bool enumerateNames(JSContext *cx, JS::HandleObject wrapper, unsigned flags,
JS::AutoIdVector &props);
static bool call(JSContext *cx, JS::HandleObject wrapper,
const JS::CallArgs &args, const js::Wrapper& baseInstance)
{
JSXrayTraits &self = JSXrayTraits::singleton;
JS::RootedObject holder(cx, self.ensureHolder(cx, wrapper));
if (self.getProtoKey(holder) == JSProto_Function)
return baseInstance.call(cx, wrapper, args);
JS::RootedValue v(cx, JS::ObjectValue(*wrapper));
js_ReportIsNotFunction(cx, v);
return false;
}
static bool construct(JSContext *cx, JS::HandleObject wrapper,
const JS::CallArgs &args, const js::Wrapper& baseInstance)
{
JSXrayTraits &self = JSXrayTraits::singleton;
JS::RootedObject holder(cx, self.ensureHolder(cx, wrapper));
if (self.getProtoKey(holder) == JSProto_Function)
return baseInstance.construct(cx, wrapper, args);
JS::RootedValue v(cx, JS::ObjectValue(*wrapper));
js_ReportIsNotFunction(cx, v);
return false;
}
bool getPrototypeOf(JSContext *cx, JS::HandleObject wrapper,
JS::HandleObject target,
JS::MutableHandleObject protop)
{
JS::RootedObject holder(cx, ensureHolder(cx, wrapper));
JSProtoKey key = getProtoKey(holder);
if (isPrototype(holder)) {
JSProtoKey parentKey = js::ParentKeyForStandardClass(key);
if (parentKey == JSProto_Null) {
protop.set(nullptr);
return true;
}
key = parentKey;
}
{
JSAutoCompartment ac(cx, target);
if (!JS_GetClassPrototype(cx, key, protop))
return false;
}
return JS_WrapObject(cx, protop);
}
virtual void preserveWrapper(JSObject *target) MOZ_OVERRIDE {
// In the case of pure JS objects, there is no underlying object, and
// the target is the canonical representation of state. If it gets
// collected, then expandos and such should be collected too. So there's
// nothing to do here.
}
enum {
SLOT_PROTOKEY = 0,
SLOT_ISPROTOTYPE,
SLOT_CONSTRUCTOR_FOR,
SLOT_COUNT
};
virtual JSObject* createHolder(JSContext *cx, JSObject *wrapper) MOZ_OVERRIDE;
static JSProtoKey getProtoKey(JSObject *holder) {
int32_t key = js::GetReservedSlot(holder, SLOT_PROTOKEY).toInt32();
return static_cast<JSProtoKey>(key);
}
static bool isPrototype(JSObject *holder) {
return js::GetReservedSlot(holder, SLOT_ISPROTOTYPE).toBoolean();
}
static JSProtoKey constructorFor(JSObject *holder) {
int32_t key = js::GetReservedSlot(holder, SLOT_CONSTRUCTOR_FOR).toInt32();
return static_cast<JSProtoKey>(key);
}
static bool getOwnPropertyFromTargetIfSafe(JSContext *cx,
JS::HandleObject target,
JS::HandleObject wrapper,
JS::HandleId id,
JS::MutableHandle<JSPropertyDescriptor> desc);
static const JSClass HolderClass;
static JSXrayTraits singleton;
};
// These traits are used when the target is not Xrayable and we therefore want
// to make it opaque modulo the usual Xray machinery (like expandos and
// .wrappedJSObject).
class OpaqueXrayTraits : public XrayTraits
{
public:
enum {
HasPrototype = 1
};
static const XrayType Type = XrayForOpaqueObject;
virtual bool resolveNativeProperty(JSContext *cx, JS::HandleObject wrapper,
JS::HandleObject holder, JS::HandleId id,
JS::MutableHandle<JSPropertyDescriptor> desc) MOZ_OVERRIDE
{
MOZ_CRASH("resolveNativeProperty hook should never be called with HasPrototype = 1");
}
virtual bool resolveOwnProperty(JSContext *cx, const js::Wrapper &jsWrapper, JS::HandleObject wrapper,
JS::HandleObject holder, JS::HandleId id,
JS::MutableHandle<JSPropertyDescriptor> desc) MOZ_OVERRIDE;
bool defineProperty(JSContext *cx, JS::HandleObject wrapper, JS::HandleId id,
JS::MutableHandle<JSPropertyDescriptor> desc,
JS::Handle<JSPropertyDescriptor> existingDesc, bool *defined)
{
*defined = false;
return true;
}
virtual bool enumerateNames(JSContext *cx, JS::HandleObject wrapper, unsigned flags,
JS::AutoIdVector &props)
{
return true;
}
static bool call(JSContext *cx, JS::HandleObject wrapper,
const JS::CallArgs &args, const js::Wrapper& baseInstance)
{
JS::RootedValue v(cx, JS::ObjectValue(*wrapper));
js_ReportIsNotFunction(cx, v);
return false;
}
static bool construct(JSContext *cx, JS::HandleObject wrapper,
const JS::CallArgs &args, const js::Wrapper& baseInstance)
{
JS::RootedValue v(cx, JS::ObjectValue(*wrapper));
js_ReportIsNotFunction(cx, v);
return false;
}
bool getPrototypeOf(JSContext *cx, JS::HandleObject wrapper,
JS::HandleObject target,
JS::MutableHandleObject protop)
{
// Opaque wrappers just get targetGlobal.Object.prototype as their
// prototype. This is preferable to using a null prototype because it
// lets things like |toString| and |__proto__| work.
{
JSAutoCompartment ac(cx, target);
if (!JS_GetClassPrototype(cx, JSProto_Object, protop))
return false;
}
return JS_WrapObject(cx, protop);
}
static const char *className(JSContext *cx, JS::HandleObject wrapper, const js::Wrapper& baseInstance) {
return "Opaque";
}
virtual void preserveWrapper(JSObject *target) MOZ_OVERRIDE { }
virtual JSObject* createHolder(JSContext *cx, JSObject *wrapper) MOZ_OVERRIDE
{
JS::RootedObject global(cx, JS_GetGlobalForObject(cx, wrapper));
return JS_NewObjectWithGivenProto(cx, nullptr, JS::NullPtr(), global);
}
static OpaqueXrayTraits singleton;
};
XrayType GetXrayType(JSObject *obj);
XrayTraits* GetXrayTraits(JSObject *obj);
// NB: Base *must* derive from JSProxyHandler
template <typename Base, typename Traits = XPCWrappedNativeXrayTraits >
class XrayWrapper : public Base {
public:
MOZ_CONSTEXPR explicit XrayWrapper(unsigned flags)
: Base(flags | WrapperFactory::IS_XRAY_WRAPPER_FLAG, Traits::HasPrototype)
{ };
/* Fundamental proxy traps. */
virtual bool isExtensible(JSContext *cx, JS::Handle<JSObject*> wrapper, bool *extensible) const MOZ_OVERRIDE;
virtual bool preventExtensions(JSContext *cx, JS::Handle<JSObject*> wrapper) const MOZ_OVERRIDE;
virtual bool getPropertyDescriptor(JSContext *cx, JS::Handle<JSObject*> wrapper, JS::Handle<jsid> id,
JS::MutableHandle<JSPropertyDescriptor> desc) const MOZ_OVERRIDE;
virtual bool getOwnPropertyDescriptor(JSContext *cx, JS::Handle<JSObject*> wrapper, JS::Handle<jsid> id,
JS::MutableHandle<JSPropertyDescriptor> desc) const MOZ_OVERRIDE;
virtual bool defineProperty(JSContext *cx, JS::Handle<JSObject*> wrapper, JS::Handle<jsid> id,
JS::MutableHandle<JSPropertyDescriptor> desc) const MOZ_OVERRIDE;
virtual bool getOwnPropertyNames(JSContext *cx, JS::Handle<JSObject*> wrapper,
JS::AutoIdVector &props) const MOZ_OVERRIDE;
virtual bool delete_(JSContext *cx, JS::Handle<JSObject*> wrapper,
JS::Handle<jsid> id, bool *bp) const MOZ_OVERRIDE;
virtual bool enumerate(JSContext *cx, JS::Handle<JSObject*> wrapper, JS::AutoIdVector &props) const MOZ_OVERRIDE;
/* Derived proxy traps. */
virtual bool get(JSContext *cx, JS::Handle<JSObject*> wrapper, JS::Handle<JSObject*> receiver,
JS::Handle<jsid> id, JS::MutableHandle<JS::Value> vp) const MOZ_OVERRIDE;
virtual bool set(JSContext *cx, JS::Handle<JSObject*> wrapper, JS::Handle<JSObject*> receiver,
JS::Handle<jsid> id, bool strict, JS::MutableHandle<JS::Value> vp) const MOZ_OVERRIDE;
virtual bool has(JSContext *cx, JS::Handle<JSObject*> wrapper, JS::Handle<jsid> id,
bool *bp) const MOZ_OVERRIDE;
virtual bool hasOwn(JSContext *cx, JS::Handle<JSObject*> wrapper, JS::Handle<jsid> id,
bool *bp) const MOZ_OVERRIDE;
virtual bool keys(JSContext *cx, JS::Handle<JSObject*> wrapper,
JS::AutoIdVector &props) const MOZ_OVERRIDE;
virtual bool iterate(JSContext *cx, JS::Handle<JSObject*> wrapper, unsigned flags,
JS::MutableHandle<JS::Value> vp) const MOZ_OVERRIDE;
virtual bool call(JSContext *cx, JS::Handle<JSObject*> wrapper,
const JS::CallArgs &args) const MOZ_OVERRIDE;
virtual bool construct(JSContext *cx, JS::Handle<JSObject*> wrapper,
const JS::CallArgs &args) const MOZ_OVERRIDE;
virtual const char *className(JSContext *cx, JS::HandleObject proxy) const MOZ_OVERRIDE;
virtual bool defaultValue(JSContext *cx, JS::HandleObject wrapper,
JSType hint, JS::MutableHandleValue vp)
const MOZ_OVERRIDE;
virtual bool getPrototypeOf(JSContext *cx, JS::HandleObject wrapper,
JS::MutableHandleObject protop) const MOZ_OVERRIDE;
virtual bool setPrototypeOf(JSContext *cx, JS::HandleObject wrapper,
JS::HandleObject proto, bool *bp) const MOZ_OVERRIDE;
static const XrayWrapper singleton;
private:
template <bool HasPrototype>
typename mozilla::EnableIf<HasPrototype, bool>::Type
getPrototypeOfHelper(JSContext *cx, JS::HandleObject wrapper,
JS::HandleObject target, JS::MutableHandleObject protop) const
{
return Traits::singleton.getPrototypeOf(cx, wrapper, target, protop);
}
template <bool HasPrototype>
typename mozilla::EnableIf<!HasPrototype, bool>::Type
getPrototypeOfHelper(JSContext *cx, JS::HandleObject wrapper,
JS::HandleObject target, JS::MutableHandleObject protop) const
{
return Base::getPrototypeOf(cx, wrapper, protop);
}
bool getPrototypeOfHelper(JSContext *cx, JS::HandleObject wrapper,
JS::HandleObject target, JS::MutableHandleObject protop) const
{
return getPrototypeOfHelper<Traits::HasPrototype>(cx, wrapper, target,
protop);
}
protected:
bool enumerate(JSContext *cx, JS::Handle<JSObject*> wrapper, unsigned flags,
JS::AutoIdVector &props) const;
};
#define PermissiveXrayXPCWN xpc::XrayWrapper<js::CrossCompartmentWrapper, xpc::XPCWrappedNativeXrayTraits>
#define SecurityXrayXPCWN xpc::XrayWrapper<js::CrossCompartmentSecurityWrapper, xpc::XPCWrappedNativeXrayTraits>
#define PermissiveXrayDOM xpc::XrayWrapper<js::CrossCompartmentWrapper, xpc::DOMXrayTraits>
#define SecurityXrayDOM xpc::XrayWrapper<js::CrossCompartmentSecurityWrapper, xpc::DOMXrayTraits>
#define PermissiveXrayJS xpc::XrayWrapper<js::CrossCompartmentWrapper, xpc::JSXrayTraits>
#define PermissiveXrayOpaque xpc::XrayWrapper<js::CrossCompartmentWrapper, xpc::OpaqueXrayTraits>
#define SCSecurityXrayXPCWN xpc::XrayWrapper<js::SameCompartmentSecurityWrapper, xpc::XPCWrappedNativeXrayTraits>
class SandboxProxyHandler : public js::Wrapper {
public:
MOZ_CONSTEXPR SandboxProxyHandler() : js::Wrapper(0)
{
}
virtual bool getPropertyDescriptor(JSContext *cx, JS::Handle<JSObject*> proxy,
JS::Handle<jsid> id,
JS::MutableHandle<JSPropertyDescriptor> desc) const MOZ_OVERRIDE;
virtual bool getOwnPropertyDescriptor(JSContext *cx, JS::Handle<JSObject*> proxy,
JS::Handle<jsid> id,
JS::MutableHandle<JSPropertyDescriptor> desc) const MOZ_OVERRIDE;
// We just forward the derived traps to the BaseProxyHandler versions which
// implement them in terms of the fundamental traps.
virtual bool has(JSContext *cx, JS::Handle<JSObject*> proxy, JS::Handle<jsid> id,
bool *bp) const MOZ_OVERRIDE;
virtual bool hasOwn(JSContext *cx, JS::Handle<JSObject*> proxy, JS::Handle<jsid> id,
bool *bp) const MOZ_OVERRIDE;
virtual bool get(JSContext *cx, JS::Handle<JSObject*> proxy, JS::Handle<JSObject*> receiver,
JS::Handle<jsid> id, JS::MutableHandle<JS::Value> vp) const MOZ_OVERRIDE;
virtual bool set(JSContext *cx, JS::Handle<JSObject*> proxy, JS::Handle<JSObject*> receiver,
JS::Handle<jsid> id, bool strict, JS::MutableHandle<JS::Value> vp) const MOZ_OVERRIDE;
virtual bool keys(JSContext *cx, JS::Handle<JSObject*> proxy,
JS::AutoIdVector &props) const MOZ_OVERRIDE;
virtual bool iterate(JSContext *cx, JS::Handle<JSObject*> proxy, unsigned flags,
JS::MutableHandle<JS::Value> vp) const MOZ_OVERRIDE;
};
extern const SandboxProxyHandler sandboxProxyHandler;
// A proxy handler that lets us wrap callables and invoke them with
// the correct this object, while forwarding all other operations down
// to them directly.
class SandboxCallableProxyHandler : public js::Wrapper {
public:
MOZ_CONSTEXPR SandboxCallableProxyHandler() : js::Wrapper(0)
{
}
virtual bool call(JSContext *cx, JS::Handle<JSObject*> proxy,
const JS::CallArgs &args) const MOZ_OVERRIDE;
};
extern const SandboxCallableProxyHandler sandboxCallableProxyHandler;
class AutoSetWrapperNotShadowing;
}
#endif