DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Mercurial (d38398e5144e)

VCS Links

Flags

WrapperOptions

Macros

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385
/* -*- 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 jswrapper_h
#define jswrapper_h

#include "mozilla/Attributes.h"

#include "js/Proxy.h"

namespace js {

/*
 * Helper for Wrapper::New default options.
 *
 * Callers of Wrapper::New() who wish to specify a prototype for the created
 * Wrapper, *MUST* construct a WrapperOptions with a JSContext.
 */
class MOZ_STACK_CLASS WrapperOptions : public ProxyOptions {
  public:
    WrapperOptions() : ProxyOptions(false),
                       proto_()
    {}

    explicit WrapperOptions(JSContext* cx) : ProxyOptions(false),
                                             proto_()
    {
        proto_.emplace(cx);
    }

    inline JSObject* proto() const;
    WrapperOptions& setProto(JSObject* protoArg) {
        MOZ_ASSERT(proto_);
        *proto_ = protoArg;
        return *this;
    }

  private:
    mozilla::Maybe<JS::RootedObject> proto_;
};

/*
 * A wrapper is a proxy with a target object to which it generally forwards
 * operations, but may restrict access to certain operations or augment those
 * operations in various ways.
 *
 * A wrapper can be "unwrapped" in C++, exposing the underlying object.
 * Callers should be careful to avoid unwrapping security wrappers in the wrong
 * context.
 *
 * Important: If you add a method implementation here, you probably also need
 * to add an override in CrossCompartmentWrapper. If you don't, you risk
 * compartment mismatches. See bug 945826 comment 0.
 */
class JS_FRIEND_API(Wrapper) : public BaseProxyHandler
{
    unsigned mFlags;

  public:
    explicit constexpr Wrapper(unsigned aFlags, bool aHasPrototype = false,
                                   bool aHasSecurityPolicy = false)
      : BaseProxyHandler(&family, aHasPrototype, aHasSecurityPolicy),
        mFlags(aFlags)
    { }

    virtual bool finalizeInBackground(const Value& priv) const override;

    /* Standard internal methods. */
    virtual bool getOwnPropertyDescriptor(JSContext* cx, HandleObject proxy, HandleId id,
                                          MutableHandle<PropertyDescriptor> desc) const override;
    virtual bool defineProperty(JSContext* cx, HandleObject proxy, HandleId id,
                                Handle<PropertyDescriptor> desc,
                                ObjectOpResult& result) const override;
    virtual bool ownPropertyKeys(JSContext* cx, HandleObject proxy,
                                 AutoIdVector& props) const override;
    virtual bool delete_(JSContext* cx, HandleObject proxy, HandleId id,
                         ObjectOpResult& result) const override;
    virtual bool enumerate(JSContext* cx, HandleObject proxy,
                           MutableHandleObject objp) const override;
    virtual bool getPrototype(JSContext* cx, HandleObject proxy,
                              MutableHandleObject protop) const override;
    virtual bool setPrototype(JSContext* cx, HandleObject proxy, HandleObject proto,
                              ObjectOpResult& result) const override;
    virtual bool getPrototypeIfOrdinary(JSContext* cx, HandleObject proxy, bool* isOrdinary,
                                        MutableHandleObject protop) const override;
    virtual bool setImmutablePrototype(JSContext* cx, HandleObject proxy,
                                       bool* succeeded) const override;
    virtual bool preventExtensions(JSContext* cx, HandleObject proxy,
                                   ObjectOpResult& result) const override;
    virtual bool isExtensible(JSContext* cx, HandleObject proxy, bool* extensible) const override;
    virtual bool has(JSContext* cx, HandleObject proxy, HandleId id,
                     bool* bp) const override;
    virtual bool get(JSContext* cx, HandleObject proxy, HandleValue receiver,
                     HandleId id, MutableHandleValue vp) const override;
    virtual bool set(JSContext* cx, HandleObject proxy, HandleId id, HandleValue v,
                     HandleValue receiver, ObjectOpResult& result) const override;
    virtual bool call(JSContext* cx, HandleObject proxy, const CallArgs& args) const override;
    virtual bool construct(JSContext* cx, HandleObject proxy, const CallArgs& args) const override;

    /* SpiderMonkey extensions. */
    virtual bool getPropertyDescriptor(JSContext* cx, HandleObject proxy, HandleId id,
                                       MutableHandle<PropertyDescriptor> desc) const override;
    virtual bool hasOwn(JSContext* cx, HandleObject proxy, HandleId id,
                        bool* bp) const override;
    virtual bool getOwnEnumerablePropertyKeys(JSContext* cx, HandleObject proxy,
                                              AutoIdVector& props) const override;
    virtual bool nativeCall(JSContext* cx, IsAcceptableThis test, NativeImpl impl,
                            const CallArgs& args) const override;
    virtual bool hasInstance(JSContext* cx, HandleObject proxy, MutableHandleValue v,
                             bool* bp) const override;
    virtual bool getBuiltinClass(JSContext* cx, HandleObject proxy, ESClass* cls) const override;
    virtual bool isArray(JSContext* cx, HandleObject proxy,
                         JS::IsArrayAnswer* answer) const override;
    virtual const char* className(JSContext* cx, HandleObject proxy) const override;
    virtual JSString* fun_toString(JSContext* cx, HandleObject proxy,
                                   unsigned indent) const override;
    virtual bool regexp_toShared(JSContext* cx, HandleObject proxy,
                                 RegExpGuard* g) const override;
    virtual bool boxedValue_unbox(JSContext* cx, HandleObject proxy,
                                  MutableHandleValue vp) const override;
    virtual bool isCallable(JSObject* obj) const override;
    virtual bool isConstructor(JSObject* obj) const override;
    virtual JSObject* weakmapKeyDelegate(JSObject* proxy) const override;

  public:
    using BaseProxyHandler::Action;

    enum Flags {
        CROSS_COMPARTMENT = 1 << 0,
        LAST_USED_FLAG = CROSS_COMPARTMENT
    };

    static JSObject* New(JSContext* cx, JSObject* obj, const Wrapper* handler,
                         const WrapperOptions& options = WrapperOptions());

    static JSObject* Renew(JSObject* existing, JSObject* obj, const Wrapper* handler);

    static const Wrapper* wrapperHandler(JSObject* wrapper);

    static JSObject* wrappedObject(JSObject* wrapper);

    unsigned flags() const {
        return mFlags;
    }

    static const char family;
    static const Wrapper singleton;
    static const Wrapper singletonWithPrototype;

    static JSObject* defaultProto;
};

inline JSObject*
WrapperOptions::proto() const
{
    return proto_ ? *proto_ : Wrapper::defaultProto;
}

/* Base class for all cross compartment wrapper handlers. */
class JS_FRIEND_API(CrossCompartmentWrapper) : public Wrapper
{
  public:
    explicit constexpr CrossCompartmentWrapper(unsigned aFlags, bool aHasPrototype = false,
                                                   bool aHasSecurityPolicy = false)
      : Wrapper(CROSS_COMPARTMENT | aFlags, aHasPrototype, aHasSecurityPolicy)
    { }

    /* Standard internal methods. */
    virtual bool getOwnPropertyDescriptor(JSContext* cx, HandleObject wrapper, HandleId id,
                                          MutableHandle<PropertyDescriptor> desc) const override;
    virtual bool defineProperty(JSContext* cx, HandleObject wrapper, HandleId id,
                                Handle<PropertyDescriptor> desc,
                                ObjectOpResult& result) const override;
    virtual bool ownPropertyKeys(JSContext* cx, HandleObject wrapper,
                                 AutoIdVector& props) const override;
    virtual bool delete_(JSContext* cx, HandleObject wrapper, HandleId id,
                         ObjectOpResult& result) const override;
    virtual bool enumerate(JSContext* cx, HandleObject wrapper, MutableHandleObject objp) const override;
    virtual bool getPrototype(JSContext* cx, HandleObject proxy,
                              MutableHandleObject protop) const override;
    virtual bool setPrototype(JSContext* cx, HandleObject proxy, HandleObject proto,
                              ObjectOpResult& result) const override;

    virtual bool getPrototypeIfOrdinary(JSContext* cx, HandleObject proxy, bool* isOrdinary,
                                        MutableHandleObject protop) const override;
    virtual bool setImmutablePrototype(JSContext* cx, HandleObject proxy,
                                       bool* succeeded) const override;
    virtual bool preventExtensions(JSContext* cx, HandleObject wrapper,
                                   ObjectOpResult& result) const override;
    virtual bool isExtensible(JSContext* cx, HandleObject wrapper, bool* extensible) const override;
    virtual bool has(JSContext* cx, HandleObject wrapper, HandleId id, bool* bp) const override;
    virtual bool get(JSContext* cx, HandleObject wrapper, HandleValue receiver,
                     HandleId id, MutableHandleValue vp) const override;
    virtual bool set(JSContext* cx, HandleObject wrapper, HandleId id, HandleValue v,
                     HandleValue receiver, ObjectOpResult& result) const override;
    virtual bool call(JSContext* cx, HandleObject wrapper, const CallArgs& args) const override;
    virtual bool construct(JSContext* cx, HandleObject wrapper, const CallArgs& args) const override;

    /* SpiderMonkey extensions. */
    virtual bool getPropertyDescriptor(JSContext* cx, HandleObject wrapper, HandleId id,
                                       MutableHandle<PropertyDescriptor> desc) const override;
    virtual bool hasOwn(JSContext* cx, HandleObject wrapper, HandleId id, bool* bp) const override;
    virtual bool getOwnEnumerablePropertyKeys(JSContext* cx, HandleObject wrapper,
                                              AutoIdVector& props) const override;
    virtual bool nativeCall(JSContext* cx, IsAcceptableThis test, NativeImpl impl,
                            const CallArgs& args) const override;
    virtual bool hasInstance(JSContext* cx, HandleObject wrapper, MutableHandleValue v,
                             bool* bp) const override;
    virtual const char* className(JSContext* cx, HandleObject proxy) const override;
    virtual JSString* fun_toString(JSContext* cx, HandleObject wrapper,
                                   unsigned indent) const override;
    virtual bool regexp_toShared(JSContext* cx, HandleObject proxy, RegExpGuard* g) const override;
    virtual bool boxedValue_unbox(JSContext* cx, HandleObject proxy, MutableHandleValue vp) const override;

    // Allocate CrossCompartmentWrappers in the nursery.
    virtual bool canNurseryAllocate() const override { return true; }

    static const CrossCompartmentWrapper singleton;
    static const CrossCompartmentWrapper singletonWithPrototype;
};

class JS_FRIEND_API(OpaqueCrossCompartmentWrapper) : public CrossCompartmentWrapper
{
  public:
    explicit constexpr OpaqueCrossCompartmentWrapper() : CrossCompartmentWrapper(0)
    { }

    /* Standard internal methods. */
    virtual bool getOwnPropertyDescriptor(JSContext* cx, HandleObject wrapper, HandleId id,
                                          MutableHandle<PropertyDescriptor> desc) const override;
    virtual bool defineProperty(JSContext* cx, HandleObject wrapper, HandleId id,
                                Handle<PropertyDescriptor> desc,
                                ObjectOpResult& result) const override;
    virtual bool ownPropertyKeys(JSContext* cx, HandleObject wrapper,
                                 AutoIdVector& props) const override;
    virtual bool delete_(JSContext* cx, HandleObject wrapper, HandleId id,
                         ObjectOpResult& result) const override;
    virtual bool enumerate(JSContext* cx, HandleObject wrapper,
                           MutableHandleObject objp) const override;
    virtual bool getPrototype(JSContext* cx, HandleObject wrapper,
                              MutableHandleObject protop) const override;
    virtual bool setPrototype(JSContext* cx, HandleObject wrapper, HandleObject proto,
                              ObjectOpResult& result) const override;
    virtual bool getPrototypeIfOrdinary(JSContext* cx, HandleObject wrapper, bool* isOrdinary,
                                        MutableHandleObject protop) const override;
    virtual bool setImmutablePrototype(JSContext* cx, HandleObject wrapper,
                                       bool* succeeded) const override;
    virtual bool preventExtensions(JSContext* cx, HandleObject wrapper,
                                   ObjectOpResult& result) const override;
    virtual bool isExtensible(JSContext* cx, HandleObject wrapper, bool* extensible) const override;
    virtual bool has(JSContext* cx, HandleObject wrapper, HandleId id,
                     bool* bp) const override;
    virtual bool get(JSContext* cx, HandleObject wrapper, HandleValue receiver,
                     HandleId id, MutableHandleValue vp) const override;
    virtual bool set(JSContext* cx, HandleObject wrapper, HandleId id, HandleValue v,
                     HandleValue receiver, ObjectOpResult& result) const override;
    virtual bool call(JSContext* cx, HandleObject wrapper, const CallArgs& args) const override;
    virtual bool construct(JSContext* cx, HandleObject wrapper, const CallArgs& args) const override;

    /* SpiderMonkey extensions. */
    virtual bool getPropertyDescriptor(JSContext* cx, HandleObject wrapper, HandleId id,
                                       MutableHandle<PropertyDescriptor> desc) const override;
    virtual bool hasOwn(JSContext* cx, HandleObject wrapper, HandleId id,
                        bool* bp) const override;
    virtual bool getOwnEnumerablePropertyKeys(JSContext* cx, HandleObject wrapper,
                                              AutoIdVector& props) const override;
    virtual bool getBuiltinClass(JSContext* cx, HandleObject wrapper, ESClass* cls) const override;
    virtual bool isArray(JSContext* cx, HandleObject obj,
                         JS::IsArrayAnswer* answer) const override;
    virtual const char* className(JSContext* cx, HandleObject wrapper) const override;
    virtual JSString* fun_toString(JSContext* cx, HandleObject proxy, unsigned indent) const override;

    static const OpaqueCrossCompartmentWrapper singleton;
};

/*
 * Base class for security wrappers. A security wrapper is potentially hiding
 * all or part of some wrapped object thus SecurityWrapper defaults to denying
 * access to the wrappee. This is the opposite of Wrapper which tries to be
 * completely transparent.
 *
 * NB: Currently, only a few ProxyHandler operations are overridden to deny
 * access, relying on derived SecurityWrapper to block access when necessary.
 */
template <class Base>
class JS_FRIEND_API(SecurityWrapper) : public Base
{
  public:
    explicit constexpr SecurityWrapper(unsigned flags, bool hasPrototype = false)
      : Base(flags, hasPrototype, /* hasSecurityPolicy = */ true)
    { }

    virtual bool enter(JSContext* cx, HandleObject wrapper, HandleId id, Wrapper::Action act,
                       bool mayThrow, bool* bp) const override;

    virtual bool defineProperty(JSContext* cx, HandleObject wrapper, HandleId id,
                                Handle<PropertyDescriptor> desc,
                                ObjectOpResult& result) const override;
    virtual bool isExtensible(JSContext* cx, HandleObject wrapper, bool* extensible) const override;
    virtual bool preventExtensions(JSContext* cx, HandleObject wrapper,
                                   ObjectOpResult& result) const override;
    virtual bool setPrototype(JSContext* cx, HandleObject proxy, HandleObject proto,
                              ObjectOpResult& result) const override;
    virtual bool setImmutablePrototype(JSContext* cx, HandleObject proxy, bool* succeeded) const override;

    virtual bool nativeCall(JSContext* cx, IsAcceptableThis test, NativeImpl impl,
                            const CallArgs& args) const override;
    virtual bool getBuiltinClass(JSContext* cx, HandleObject wrapper, ESClass* cls) const override;
    virtual bool isArray(JSContext* cx, HandleObject wrapper, JS::IsArrayAnswer* answer) const override;
    virtual bool regexp_toShared(JSContext* cx, HandleObject proxy, RegExpGuard* g) const override;
    virtual bool boxedValue_unbox(JSContext* cx, HandleObject proxy, MutableHandleValue vp) const override;

    // Allow isCallable and isConstructor. They used to be class-level, and so could not be guarded
    // against.

    virtual bool watch(JSContext* cx, JS::HandleObject proxy, JS::HandleId id,
                       JS::HandleObject callable) const override;
    virtual bool unwatch(JSContext* cx, JS::HandleObject proxy, JS::HandleId id) const override;

    /*
     * Allow our subclasses to select the superclass behavior they want without
     * needing to specify an exact superclass.
     */
    typedef Base Permissive;
    typedef SecurityWrapper<Base> Restrictive;
};

typedef SecurityWrapper<CrossCompartmentWrapper> CrossCompartmentSecurityWrapper;

extern JSObject*
TransparentObjectWrapper(JSContext* cx, HandleObject existing, HandleObject obj);

inline bool
IsWrapper(JSObject* obj)
{
    return IsProxy(obj) && GetProxyHandler(obj)->family() == &Wrapper::family;
}

// Given a JSObject, returns that object stripped of wrappers. If
// stopAtWindowProxy is true, then this returns the WindowProxy if it was
// previously wrapped. Otherwise, this returns the first object for
// which JSObject::isWrapper returns false.
JS_FRIEND_API(JSObject*)
UncheckedUnwrap(JSObject* obj, bool stopAtWindowProxy = true, unsigned* flagsp = nullptr);

// Given a JSObject, returns that object stripped of wrappers. At each stage,
// the security wrapper has the opportunity to veto the unwrap. If
// stopAtWindowProxy is true, then this returns the WindowProxy if it was
// previously wrapped.
JS_FRIEND_API(JSObject*)
CheckedUnwrap(JSObject* obj, bool stopAtWindowProxy = true);

// Unwrap only the outermost security wrapper, with the same semantics as
// above. This is the checked version of Wrapper::wrappedObject.
JS_FRIEND_API(JSObject*)
UnwrapOneChecked(JSObject* obj, bool stopAtWindowProxy = true);

void
ReportAccessDenied(JSContext* cx);

JS_FRIEND_API(bool)
IsCrossCompartmentWrapper(JSObject* obj);

void
NukeCrossCompartmentWrapper(JSContext* cx, JSObject* wrapper);

void
RemapWrapper(JSContext* cx, JSObject* wobj, JSObject* newTarget);

JS_FRIEND_API(bool)
RemapAllWrappersForObject(JSContext* cx, JSObject* oldTarget,
                          JSObject* newTarget);

// API to recompute all cross-compartment wrappers whose source and target
// match the given filters.
JS_FRIEND_API(bool)
RecomputeWrappers(JSContext* cx, const CompartmentFilter& sourceFilter,
                  const CompartmentFilter& targetFilter);

} /* namespace js */

#endif /* jswrapper_h */