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Diffstat (limited to 'js/src/proxy/ScriptedProxyHandler.cpp')
| -rw-r--r-- | js/src/proxy/ScriptedProxyHandler.cpp | 1577 |
1 files changed, 1577 insertions, 0 deletions
diff --git a/js/src/proxy/ScriptedProxyHandler.cpp b/js/src/proxy/ScriptedProxyHandler.cpp new file mode 100644 index 0000000000..43ba8de0a3 --- /dev/null +++ b/js/src/proxy/ScriptedProxyHandler.cpp @@ -0,0 +1,1577 @@ +/* -*- 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 "proxy/ScriptedProxyHandler.h" + +#include "mozilla/Maybe.h" + +#include "jsapi.h" + +#include "builtin/Object.h" +#include "js/CallAndConstruct.h" // JS::Construct, JS::IsCallable +#include "js/CharacterEncoding.h" +#include "js/friend/ErrorMessages.h" // js::GetErrorMessage, JSMSG_* +#include "js/PropertyDescriptor.h" // JS::FromPropertyDescriptor +#include "vm/EqualityOperations.h" // js::SameValue +#include "vm/Interpreter.h" // js::Call +#include "vm/JSFunction.h" +#include "vm/JSObject.h" +#include "vm/PlainObject.h" // js::PlainObject + +#include "vm/JSObject-inl.h" +#include "vm/NativeObject-inl.h" + +using namespace js; + +using JS::IsArrayAnswer; + +using mozilla::Maybe; + +// ES2022 rev 33fe30f9a6b0dc81826f2f217167a89c025779a0 +// IsCompatiblePropertyDescriptor. BUT that method just calls +// ValidateAndApplyPropertyDescriptor with two additional constant arguments. +// Therefore step numbering is from the latter method, and resulting dead code +// has been removed. + +// If an exception should be thrown, we will set errorDetails. +static bool IsCompatiblePropertyDescriptor( + JSContext* cx, bool extensible, Handle<PropertyDescriptor> desc, + Handle<Maybe<PropertyDescriptor>> current, const char** errorDetails) { + // precondition: we won't set details if checks pass, so it must be null + // here. + MOZ_ASSERT(*errorDetails == nullptr); + + // Step 2. + if (current.isNothing()) { + // Step 2.a-b,e. As |O| is always undefined, steps 2.c-d fall away. + if (!extensible) { + static const char DETAILS_NOT_EXTENSIBLE[] = + "proxy can't report an extensible object as non-extensible"; + *errorDetails = DETAILS_NOT_EXTENSIBLE; + } + return true; + } + + current->assertComplete(); + + // Step 3. + if (!desc.hasValue() && !desc.hasWritable() && !desc.hasGetter() && + !desc.hasSetter() && !desc.hasEnumerable() && !desc.hasConfigurable()) { + return true; + } + + // Step 4. + if (!current->configurable()) { + // Step 4.a. + if (desc.hasConfigurable() && desc.configurable()) { + static const char DETAILS_CANT_REPORT_NC_AS_C[] = + "proxy can't report an existing non-configurable property as " + "configurable"; + *errorDetails = DETAILS_CANT_REPORT_NC_AS_C; + return true; + } + + // Step 4.b. + if (desc.hasEnumerable() && desc.enumerable() != current->enumerable()) { + static const char DETAILS_ENUM_DIFFERENT[] = + "proxy can't report a different 'enumerable' from target when target " + "is not configurable"; + *errorDetails = DETAILS_ENUM_DIFFERENT; + return true; + } + } + + // Step 5. + if (desc.isGenericDescriptor()) { + return true; + } + + // Step 6. + if (current->isDataDescriptor() != desc.isDataDescriptor()) { + // Steps 6.a., 10. As |O| is always undefined, steps 6.b-c fall away. + if (!current->configurable()) { + static const char DETAILS_CURRENT_NC_DIFF_TYPE[] = + "proxy can't report a different descriptor type when target is not " + "configurable"; + *errorDetails = DETAILS_CURRENT_NC_DIFF_TYPE; + } + return true; + } + + // Step 7. + if (current->isDataDescriptor()) { + MOZ_ASSERT(desc.isDataDescriptor()); // by step 6 + // Step 7.a. + if (!current->configurable() && !current->writable()) { + // Step 7.a.i. + if (desc.hasWritable() && desc.writable()) { + static const char DETAILS_CANT_REPORT_NW_AS_W[] = + "proxy can't report a non-configurable, non-writable property as " + "writable"; + *errorDetails = DETAILS_CANT_REPORT_NW_AS_W; + return true; + } + + // Step 7.a.ii. + if (desc.hasValue()) { + RootedValue value(cx, current->value()); + bool same; + if (!SameValue(cx, desc.value(), value, &same)) { + return false; + } + if (!same) { + static const char DETAILS_DIFFERENT_VALUE[] = + "proxy must report the same value for the non-writable, " + "non-configurable property"; + *errorDetails = DETAILS_DIFFERENT_VALUE; + return true; + } + } + } + + // Step 7.a.ii, 10. + return true; + } + + // Step 8. + + // Step 8.a. + MOZ_ASSERT(current->isAccessorDescriptor()); // by step 7 + MOZ_ASSERT(desc.isAccessorDescriptor()); // by step 6 + + // Step 8.b. + if (current->configurable()) { + return true; + } + // Steps 8.b.i-ii. + if (desc.hasSetter() && desc.setter() != current->setter()) { + static const char DETAILS_SETTERS_DIFFERENT[] = + "proxy can't report different setters for a currently non-configurable " + "property"; + *errorDetails = DETAILS_SETTERS_DIFFERENT; + } else if (desc.hasGetter() && desc.getter() != current->getter()) { + static const char DETAILS_GETTERS_DIFFERENT[] = + "proxy can't report different getters for a currently non-configurable " + "property"; + *errorDetails = DETAILS_GETTERS_DIFFERENT; + } + + // Step 9. + // |O| is always undefined. + + // Step 10. + return true; +} + +// Get the [[ProxyHandler]] of a scripted proxy. +/* static */ +JSObject* ScriptedProxyHandler::handlerObject(const JSObject* proxy) { + MOZ_ASSERT(proxy->as<ProxyObject>().handler() == + &ScriptedProxyHandler::singleton); + return proxy->as<ProxyObject>() + .reservedSlot(ScriptedProxyHandler::HANDLER_EXTRA) + .toObjectOrNull(); +} + +// ES8 rev 0c1bd3004329336774cbc90de727cd0cf5f11e93 +// 7.3.9 GetMethod, reimplemented for proxy handler trap-getting to produce +// better error messages. +static bool GetProxyTrap(JSContext* cx, HandleObject handler, + Handle<PropertyName*> name, MutableHandleValue func) { + // Steps 2, 5. + if (!GetProperty(cx, handler, handler, name, func)) { + return false; + } + + // Step 3. + if (func.isUndefined()) { + return true; + } + + if (func.isNull()) { + func.setUndefined(); + return true; + } + + // Step 4. + if (!IsCallable(func)) { + UniqueChars bytes = EncodeAscii(cx, name); + if (!bytes) { + return false; + } + + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_BAD_TRAP, + bytes.get()); + return false; + } + + return true; +} + +// ES8 rev 0c1bd3004329336774cbc90de727cd0cf5f11e93 +// 9.5.1 Proxy.[[GetPrototypeOf]]. +bool ScriptedProxyHandler::getPrototype(JSContext* cx, HandleObject proxy, + MutableHandleObject protop) const { + // Steps 1-3. + RootedObject handler(cx, ScriptedProxyHandler::handlerObject(proxy)); + if (!handler) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, + JSMSG_PROXY_REVOKED); + return false; + } + + // Step 4. + RootedObject target(cx, proxy->as<ProxyObject>().target()); + MOZ_ASSERT(target); + + // Step 5. + RootedValue trap(cx); + if (!GetProxyTrap(cx, handler, cx->names().getPrototypeOf, &trap)) { + return false; + } + + // Step 6. + if (trap.isUndefined()) { + return GetPrototype(cx, target, protop); + } + + // Step 7. + RootedValue handlerProto(cx); + { + FixedInvokeArgs<1> args(cx); + + args[0].setObject(*target); + + handlerProto.setObject(*handler); + + if (!js::Call(cx, trap, handlerProto, args, &handlerProto)) { + return false; + } + } + + // Step 8. + if (!handlerProto.isObjectOrNull()) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, + JSMSG_BAD_GETPROTOTYPEOF_TRAP_RETURN); + return false; + } + + // Step 9. + bool extensibleTarget; + if (!IsExtensible(cx, target, &extensibleTarget)) { + return false; + } + + // Step 10. + if (extensibleTarget) { + protop.set(handlerProto.toObjectOrNull()); + return true; + } + + // Step 11. + RootedObject targetProto(cx); + if (!GetPrototype(cx, target, &targetProto)) { + return false; + } + + // Step 12. + if (handlerProto.toObjectOrNull() != targetProto) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, + JSMSG_INCONSISTENT_GETPROTOTYPEOF_TRAP); + return false; + } + + // Step 13. + protop.set(handlerProto.toObjectOrNull()); + return true; +} + +// ES8 rev 0c1bd3004329336774cbc90de727cd0cf5f11e93 +// 9.5.2 Proxy.[[SetPrototypeOf]]. +bool ScriptedProxyHandler::setPrototype(JSContext* cx, HandleObject proxy, + HandleObject proto, + ObjectOpResult& result) const { + // Steps 1-4. + RootedObject handler(cx, ScriptedProxyHandler::handlerObject(proxy)); + if (!handler) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, + JSMSG_PROXY_REVOKED); + return false; + } + + // Step 5. + RootedObject target(cx, proxy->as<ProxyObject>().target()); + MOZ_ASSERT(target); + + // Step 6. + RootedValue trap(cx); + if (!GetProxyTrap(cx, handler, cx->names().setPrototypeOf, &trap)) { + return false; + } + + // Step 7. + if (trap.isUndefined()) { + return SetPrototype(cx, target, proto, result); + } + + // Step 8. + bool booleanTrapResult; + { + FixedInvokeArgs<2> args(cx); + + args[0].setObject(*target); + args[1].setObjectOrNull(proto); + + RootedValue hval(cx, ObjectValue(*handler)); + if (!js::Call(cx, trap, hval, args, &hval)) { + return false; + } + + booleanTrapResult = ToBoolean(hval); + } + + // Step 9. + if (!booleanTrapResult) { + return result.fail(JSMSG_PROXY_SETPROTOTYPEOF_RETURNED_FALSE); + } + + // Step 10. + bool extensibleTarget; + if (!IsExtensible(cx, target, &extensibleTarget)) { + return false; + } + + // Step 11. + if (extensibleTarget) { + return result.succeed(); + } + + // Step 12. + RootedObject targetProto(cx); + if (!GetPrototype(cx, target, &targetProto)) { + return false; + } + + // Step 13. + if (proto != targetProto) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, + JSMSG_INCONSISTENT_SETPROTOTYPEOF_TRAP); + return false; + } + + // Step 14. + return result.succeed(); +} + +bool ScriptedProxyHandler::getPrototypeIfOrdinary( + JSContext* cx, HandleObject proxy, bool* isOrdinary, + MutableHandleObject protop) const { + *isOrdinary = false; + return true; +} + +// Not yet part of ES6, but hopefully to be standards-tracked -- and needed to +// handle revoked proxies in any event. +bool ScriptedProxyHandler::setImmutablePrototype(JSContext* cx, + HandleObject proxy, + bool* succeeded) const { + RootedObject target(cx, proxy->as<ProxyObject>().target()); + if (!target) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, + JSMSG_PROXY_REVOKED); + return false; + } + + return SetImmutablePrototype(cx, target, succeeded); +} + +// ES8 rev 0c1bd3004329336774cbc90de727cd0cf5f11e93 +// 9.5.4 Proxy.[[PreventExtensions]]() +bool ScriptedProxyHandler::preventExtensions(JSContext* cx, HandleObject proxy, + ObjectOpResult& result) const { + // Steps 1-3. + RootedObject handler(cx, ScriptedProxyHandler::handlerObject(proxy)); + if (!handler) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, + JSMSG_PROXY_REVOKED); + return false; + } + + // Step 4. + RootedObject target(cx, proxy->as<ProxyObject>().target()); + MOZ_ASSERT(target); + + // Step 5. + RootedValue trap(cx); + if (!GetProxyTrap(cx, handler, cx->names().preventExtensions, &trap)) { + return false; + } + + // Step 6. + if (trap.isUndefined()) { + return PreventExtensions(cx, target, result); + } + + // Step 7. + bool booleanTrapResult; + { + RootedValue arg(cx, ObjectValue(*target)); + RootedValue trapResult(cx); + if (!Call(cx, trap, handler, arg, &trapResult)) { + return false; + } + + booleanTrapResult = ToBoolean(trapResult); + } + + // Step 8. + if (booleanTrapResult) { + // Step 8a. + bool targetIsExtensible; + if (!IsExtensible(cx, target, &targetIsExtensible)) { + return false; + } + + if (targetIsExtensible) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, + JSMSG_CANT_REPORT_AS_NON_EXTENSIBLE); + return false; + } + + // Step 9. + return result.succeed(); + } + + // Also step 9. + return result.fail(JSMSG_PROXY_PREVENTEXTENSIONS_RETURNED_FALSE); +} + +// ES8 rev 0c1bd3004329336774cbc90de727cd0cf5f11e93 +// 9.5.3 Proxy.[[IsExtensible]]() +bool ScriptedProxyHandler::isExtensible(JSContext* cx, HandleObject proxy, + bool* extensible) const { + // Steps 1-3. + RootedObject handler(cx, ScriptedProxyHandler::handlerObject(proxy)); + if (!handler) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, + JSMSG_PROXY_REVOKED); + return false; + } + + // Step 4. + RootedObject target(cx, proxy->as<ProxyObject>().target()); + MOZ_ASSERT(target); + + // Step 5. + RootedValue trap(cx); + if (!GetProxyTrap(cx, handler, cx->names().isExtensible, &trap)) { + return false; + } + + // Step 6. + if (trap.isUndefined()) { + return IsExtensible(cx, target, extensible); + } + + // Step 7. + bool booleanTrapResult; + { + RootedValue arg(cx, ObjectValue(*target)); + RootedValue trapResult(cx); + if (!Call(cx, trap, handler, arg, &trapResult)) { + return false; + } + + booleanTrapResult = ToBoolean(trapResult); + } + + // Steps 8. + bool targetResult; + if (!IsExtensible(cx, target, &targetResult)) { + return false; + } + + // Step 9. + if (targetResult != booleanTrapResult) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, + JSMSG_PROXY_EXTENSIBILITY); + return false; + } + + // Step 10. + *extensible = booleanTrapResult; + return true; +} + +// ES8 rev 0c1bd3004329336774cbc90de727cd0cf5f11e93 +// 9.5.5 Proxy.[[GetOwnProperty]](P) +bool ScriptedProxyHandler::getOwnPropertyDescriptor( + JSContext* cx, HandleObject proxy, HandleId id, + MutableHandle<mozilla::Maybe<PropertyDescriptor>> desc) const { + // Steps 2-4. + RootedObject handler(cx, ScriptedProxyHandler::handlerObject(proxy)); + if (!handler) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, + JSMSG_PROXY_REVOKED); + return false; + } + + // Step 5. + RootedObject target(cx, proxy->as<ProxyObject>().target()); + MOZ_ASSERT(target); + + // Step 6. + RootedValue trap(cx); + if (!GetProxyTrap(cx, handler, cx->names().getOwnPropertyDescriptor, &trap)) { + return false; + } + + // Step 7. + if (trap.isUndefined()) { + return GetOwnPropertyDescriptor(cx, target, id, desc); + } + + // Step 8. + RootedValue propKey(cx); + if (!IdToStringOrSymbol(cx, id, &propKey)) { + return false; + } + + RootedValue trapResult(cx); + RootedValue targetVal(cx, ObjectValue(*target)); + if (!Call(cx, trap, handler, targetVal, propKey, &trapResult)) { + return false; + } + + // Step 9. + if (!trapResult.isUndefined() && !trapResult.isObject()) { + return js::Throw(cx, id, JSMSG_PROXY_GETOWN_OBJORUNDEF); + } + + // Step 10. + Rooted<Maybe<PropertyDescriptor>> targetDesc(cx); + if (!GetOwnPropertyDescriptor(cx, target, id, &targetDesc)) { + return false; + } + + // Step 11. + if (trapResult.isUndefined()) { + // Step 11a. + if (targetDesc.isNothing()) { + desc.reset(); + return true; + } + + // Step 11b. + if (!targetDesc->configurable()) { + return js::Throw(cx, id, JSMSG_CANT_REPORT_NC_AS_NE); + } + + // Steps 11c-d. + bool extensibleTarget; + if (!IsExtensible(cx, target, &extensibleTarget)) { + return false; + } + + // Step 11e. + if (!extensibleTarget) { + return js::Throw(cx, id, JSMSG_CANT_REPORT_E_AS_NE); + } + + // Step 11f. + desc.reset(); + return true; + } + + // Step 12. + bool extensibleTarget; + if (!IsExtensible(cx, target, &extensibleTarget)) { + return false; + } + + // Step 13. + Rooted<PropertyDescriptor> resultDesc(cx); + if (!ToPropertyDescriptor(cx, trapResult, true, &resultDesc)) { + return false; + } + + // Step 14. + CompletePropertyDescriptor(&resultDesc); + + // Step 15. + const char* errorDetails = nullptr; + if (!IsCompatiblePropertyDescriptor(cx, extensibleTarget, resultDesc, + targetDesc, &errorDetails)) + return false; + + // Step 16. + if (errorDetails) { + return js::Throw(cx, id, JSMSG_CANT_REPORT_INVALID, errorDetails); + } + + // Step 17. + if (!resultDesc.configurable()) { + if (targetDesc.isNothing()) { + return js::Throw(cx, id, JSMSG_CANT_REPORT_NE_AS_NC); + } + + if (targetDesc->configurable()) { + return js::Throw(cx, id, JSMSG_CANT_REPORT_C_AS_NC); + } + + if (resultDesc.hasWritable() && !resultDesc.writable()) { + if (targetDesc->writable()) { + return js::Throw(cx, id, JSMSG_CANT_REPORT_W_AS_NW); + } + } + } + + // Step 18. + desc.set(mozilla::Some(resultDesc.get())); + return true; +} + +// ES8 rev 0c1bd3004329336774cbc90de727cd0cf5f11e93 +// 9.5.6 Proxy.[[DefineOwnProperty]](P, Desc) +bool ScriptedProxyHandler::defineProperty(JSContext* cx, HandleObject proxy, + HandleId id, + Handle<PropertyDescriptor> desc, + ObjectOpResult& result) const { + // Steps 2-4. + RootedObject handler(cx, ScriptedProxyHandler::handlerObject(proxy)); + if (!handler) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, + JSMSG_PROXY_REVOKED); + return false; + } + + // Step 5. + RootedObject target(cx, proxy->as<ProxyObject>().target()); + MOZ_ASSERT(target); + + // Step 6. + RootedValue trap(cx); + if (!GetProxyTrap(cx, handler, cx->names().defineProperty, &trap)) { + return false; + } + + // Step 7. + if (trap.isUndefined()) { + return DefineProperty(cx, target, id, desc, result); + } + + // Step 8. + RootedValue descObj(cx); + if (!FromPropertyDescriptorToObject(cx, desc, &descObj)) { + return false; + } + + // Step 9. + RootedValue propKey(cx); + if (!IdToStringOrSymbol(cx, id, &propKey)) { + return false; + } + + RootedValue trapResult(cx); + { + FixedInvokeArgs<3> args(cx); + + args[0].setObject(*target); + args[1].set(propKey); + args[2].set(descObj); + + RootedValue thisv(cx, ObjectValue(*handler)); + if (!Call(cx, trap, thisv, args, &trapResult)) { + return false; + } + } + + // Step 10. + if (!ToBoolean(trapResult)) { + return result.fail(JSMSG_PROXY_DEFINE_RETURNED_FALSE); + } + + // Step 11. + Rooted<Maybe<PropertyDescriptor>> targetDesc(cx); + if (!GetOwnPropertyDescriptor(cx, target, id, &targetDesc)) { + return false; + } + + // Step 12. + bool extensibleTarget; + if (!IsExtensible(cx, target, &extensibleTarget)) { + return false; + } + + // Steps 13-14. + bool settingConfigFalse = desc.hasConfigurable() && !desc.configurable(); + + // Steps 15-16. + if (targetDesc.isNothing()) { + // Step 15a. + if (!extensibleTarget) { + return js::Throw(cx, id, JSMSG_CANT_DEFINE_NEW); + } + + // Step 15b. + if (settingConfigFalse) { + return js::Throw(cx, id, JSMSG_CANT_DEFINE_NE_AS_NC); + } + } else { + // Step 16a. + const char* errorDetails = nullptr; + if (!IsCompatiblePropertyDescriptor(cx, extensibleTarget, desc, targetDesc, + &errorDetails)) + return false; + + if (errorDetails) { + return js::Throw(cx, id, JSMSG_CANT_DEFINE_INVALID, errorDetails); + } + + // Step 16b. + if (settingConfigFalse && targetDesc->configurable()) { + static const char DETAILS_CANT_REPORT_C_AS_NC[] = + "proxy can't define an existing configurable property as " + "non-configurable"; + return js::Throw(cx, id, JSMSG_CANT_DEFINE_INVALID, + DETAILS_CANT_REPORT_C_AS_NC); + } + + if (targetDesc->isDataDescriptor() && !targetDesc->configurable() && + targetDesc->writable()) { + if (desc.hasWritable() && !desc.writable()) { + static const char DETAILS_CANT_DEFINE_NW[] = + "proxy can't define an existing non-configurable writable property " + "as non-writable"; + return js::Throw(cx, id, JSMSG_CANT_DEFINE_INVALID, + DETAILS_CANT_DEFINE_NW); + } + } + } + + // Step 17. + return result.succeed(); +} + +// ES8 rev 0c1bd3004329336774cbc90de727cd0cf5f11e93 +// 7.3.17 CreateListFromArrayLike with elementTypes fixed to symbol/string. +static bool CreateFilteredListFromArrayLike(JSContext* cx, HandleValue v, + MutableHandleIdVector props) { + // Step 2. + RootedObject obj(cx, RequireObject(cx, JSMSG_OBJECT_REQUIRED_RET_OWNKEYS, + JSDVG_IGNORE_STACK, v)); + if (!obj) { + return false; + } + + // Step 3. + uint64_t len; + if (!GetLengthProperty(cx, obj, &len)) { + return false; + } + + // Steps 4-6. + RootedValue next(cx); + RootedId id(cx); + uint64_t index = 0; + while (index < len) { + // Steps 6a-b. + if (!GetElementLargeIndex(cx, obj, obj, index, &next)) { + return false; + } + + // Step 6c. + if (!next.isString() && !next.isSymbol()) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, + JSMSG_OWNKEYS_STR_SYM); + return false; + } + + if (!PrimitiveValueToId<CanGC>(cx, next, &id)) { + return false; + } + + // Step 6d. + if (!props.append(id)) { + return false; + } + + // Step 6e. + index++; + } + + // Step 7. + return true; +} + +// ES2018 draft rev aab1ea3bd4d03c85d6f4a91503b4169346ab7271 +// 9.5.11 Proxy.[[OwnPropertyKeys]]() +bool ScriptedProxyHandler::ownPropertyKeys(JSContext* cx, HandleObject proxy, + MutableHandleIdVector props) const { + // Steps 1-3. + RootedObject handler(cx, ScriptedProxyHandler::handlerObject(proxy)); + if (!handler) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, + JSMSG_PROXY_REVOKED); + return false; + } + + // Step 4. + RootedObject target(cx, proxy->as<ProxyObject>().target()); + MOZ_ASSERT(target); + + // Step 5. + RootedValue trap(cx); + if (!GetProxyTrap(cx, handler, cx->names().ownKeys, &trap)) { + return false; + } + + // Step 6. + if (trap.isUndefined()) { + return GetPropertyKeys( + cx, target, JSITER_OWNONLY | JSITER_HIDDEN | JSITER_SYMBOLS, props); + } + + // Step 7. + RootedValue trapResultArray(cx); + RootedValue targetVal(cx, ObjectValue(*target)); + if (!Call(cx, trap, handler, targetVal, &trapResultArray)) { + return false; + } + + // Step 8. + RootedIdVector trapResult(cx); + if (!CreateFilteredListFromArrayLike(cx, trapResultArray, &trapResult)) { + return false; + } + + // Steps 9, 18. + Rooted<GCHashSet<jsid>> uncheckedResultKeys( + cx, GCHashSet<jsid>(cx, trapResult.length())); + + for (size_t i = 0, len = trapResult.length(); i < len; i++) { + MOZ_ASSERT(!trapResult[i].isVoid()); + + auto ptr = uncheckedResultKeys.lookupForAdd(trapResult[i]); + if (ptr) { + return js::Throw(cx, trapResult[i], JSMSG_OWNKEYS_DUPLICATE); + } + + if (!uncheckedResultKeys.add(ptr, trapResult[i])) { + return false; + } + } + + // Step 10. + bool extensibleTarget; + if (!IsExtensible(cx, target, &extensibleTarget)) { + return false; + } + + // Steps 11-13. + RootedIdVector targetKeys(cx); + if (!GetPropertyKeys(cx, target, + JSITER_OWNONLY | JSITER_HIDDEN | JSITER_SYMBOLS, + &targetKeys)) { + return false; + } + + // Steps 14-15. + RootedIdVector targetConfigurableKeys(cx); + RootedIdVector targetNonconfigurableKeys(cx); + + // Step 16. + Rooted<Maybe<PropertyDescriptor>> desc(cx); + for (size_t i = 0; i < targetKeys.length(); ++i) { + // Step 16.a. + if (!GetOwnPropertyDescriptor(cx, target, targetKeys[i], &desc)) { + return false; + } + + // Steps 16.b-c. + if (desc.isSome() && !desc->configurable()) { + if (!targetNonconfigurableKeys.append(targetKeys[i])) { + return false; + } + } else { + if (!targetConfigurableKeys.append(targetKeys[i])) { + return false; + } + } + } + + // Step 17. + if (extensibleTarget && targetNonconfigurableKeys.empty()) { + return props.appendAll(std::move(trapResult)); + } + + // Step 19. + for (size_t i = 0; i < targetNonconfigurableKeys.length(); ++i) { + MOZ_ASSERT(!targetNonconfigurableKeys[i].isVoid()); + + auto ptr = uncheckedResultKeys.lookup(targetNonconfigurableKeys[i]); + + // Step 19.a. + if (!ptr) { + return js::Throw(cx, targetNonconfigurableKeys[i], JSMSG_CANT_SKIP_NC); + } + + // Step 19.b. + uncheckedResultKeys.remove(ptr); + } + + // Step 20. + if (extensibleTarget) { + return props.appendAll(std::move(trapResult)); + } + + // Step 21. + for (size_t i = 0; i < targetConfigurableKeys.length(); ++i) { + MOZ_ASSERT(!targetConfigurableKeys[i].isVoid()); + + auto ptr = uncheckedResultKeys.lookup(targetConfigurableKeys[i]); + + // Step 21.a. + if (!ptr) { + return js::Throw(cx, targetConfigurableKeys[i], + JSMSG_CANT_REPORT_E_AS_NE); + } + + // Step 21.b. + uncheckedResultKeys.remove(ptr); + } + + // Step 22. + if (!uncheckedResultKeys.empty()) { + RootedId id(cx, uncheckedResultKeys.all().front()); + return js::Throw(cx, id, JSMSG_CANT_REPORT_NEW); + } + + // Step 23. + return props.appendAll(std::move(trapResult)); +} + +// ES8 rev 0c1bd3004329336774cbc90de727cd0cf5f11e93 +// 9.5.10 Proxy.[[Delete]](P) +bool ScriptedProxyHandler::delete_(JSContext* cx, HandleObject proxy, + HandleId id, ObjectOpResult& result) const { + // Steps 2-4. + RootedObject handler(cx, ScriptedProxyHandler::handlerObject(proxy)); + if (!handler) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, + JSMSG_PROXY_REVOKED); + return false; + } + + // Step 5. + RootedObject target(cx, proxy->as<ProxyObject>().target()); + MOZ_ASSERT(target); + + // Step 6. + RootedValue trap(cx); + if (!GetProxyTrap(cx, handler, cx->names().deleteProperty, &trap)) { + return false; + } + + // Step 7. + if (trap.isUndefined()) { + return DeleteProperty(cx, target, id, result); + } + + // Step 8. + bool booleanTrapResult; + { + RootedValue value(cx); + if (!IdToStringOrSymbol(cx, id, &value)) { + return false; + } + + RootedValue targetVal(cx, ObjectValue(*target)); + RootedValue trapResult(cx); + if (!Call(cx, trap, handler, targetVal, value, &trapResult)) { + return false; + } + + booleanTrapResult = ToBoolean(trapResult); + } + + // Step 9. + if (!booleanTrapResult) { + return result.fail(JSMSG_PROXY_DELETE_RETURNED_FALSE); + } + + // Step 10. + Rooted<Maybe<PropertyDescriptor>> desc(cx); + if (!GetOwnPropertyDescriptor(cx, target, id, &desc)) { + return false; + } + + // Step 11. + if (desc.isNothing()) { + return result.succeed(); + } + + // Step 12. + if (!desc->configurable()) { + return Throw(cx, id, JSMSG_CANT_DELETE); + } + + bool extensible; + if (!IsExtensible(cx, target, &extensible)) { + return false; + } + + if (!extensible) { + return Throw(cx, id, JSMSG_CANT_DELETE_NON_EXTENSIBLE); + } + + // Step 13. + return result.succeed(); +} + +// ES8 rev 0c1bd3004329336774cbc90de727cd0cf5f11e93 +// 9.5.7 Proxy.[[HasProperty]](P) +bool ScriptedProxyHandler::has(JSContext* cx, HandleObject proxy, HandleId id, + bool* bp) const { + // Steps 2-4. + RootedObject handler(cx, ScriptedProxyHandler::handlerObject(proxy)); + if (!handler) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, + JSMSG_PROXY_REVOKED); + return false; + } + + // Step 5. + RootedObject target(cx, proxy->as<ProxyObject>().target()); + MOZ_ASSERT(target); + + // Step 6. + RootedValue trap(cx); + if (!GetProxyTrap(cx, handler, cx->names().has, &trap)) { + return false; + } + + // Step 7. + if (trap.isUndefined()) { + return HasProperty(cx, target, id, bp); + } + + // Step 8. + RootedValue value(cx); + if (!IdToStringOrSymbol(cx, id, &value)) { + return false; + } + + RootedValue trapResult(cx); + RootedValue targetVal(cx, ObjectValue(*target)); + if (!Call(cx, trap, handler, targetVal, value, &trapResult)) { + return false; + } + + bool booleanTrapResult = ToBoolean(trapResult); + + // Step 9. + if (!booleanTrapResult) { + // Step 9a. + Rooted<Maybe<PropertyDescriptor>> desc(cx); + if (!GetOwnPropertyDescriptor(cx, target, id, &desc)) { + return false; + } + + // Step 9b. + if (desc.isSome()) { + // Step 9b(i). + if (!desc->configurable()) { + return js::Throw(cx, id, JSMSG_CANT_REPORT_NC_AS_NE); + } + + // Step 9b(ii). + bool extensible; + if (!IsExtensible(cx, target, &extensible)) { + return false; + } + + // Step 9b(iii). + if (!extensible) { + return js::Throw(cx, id, JSMSG_CANT_REPORT_E_AS_NE); + } + } + } + + // Step 10. + *bp = booleanTrapResult; + return true; +} + +// ES8 rev 0c1bd3004329336774cbc90de727cd0cf5f11e93 +// 9.5.8 Proxy.[[GetP]](P, Receiver) +bool ScriptedProxyHandler::get(JSContext* cx, HandleObject proxy, + HandleValue receiver, HandleId id, + MutableHandleValue vp) const { + // Steps 2-4. + RootedObject handler(cx, ScriptedProxyHandler::handlerObject(proxy)); + if (!handler) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, + JSMSG_PROXY_REVOKED); + return false; + } + + // Step 5. + RootedObject target(cx, proxy->as<ProxyObject>().target()); + MOZ_ASSERT(target); + + // Steps 6. + RootedValue trap(cx); + if (!GetProxyTrap(cx, handler, cx->names().get, &trap)) { + return false; + } + + // Step 7. + if (trap.isUndefined()) { + return GetProperty(cx, target, receiver, id, vp); + } + + // Step 8. + RootedValue value(cx); + if (!IdToStringOrSymbol(cx, id, &value)) { + return false; + } + + RootedValue trapResult(cx); + { + FixedInvokeArgs<3> args(cx); + + args[0].setObject(*target); + args[1].set(value); + args[2].set(receiver); + + RootedValue thisv(cx, ObjectValue(*handler)); + if (!Call(cx, trap, thisv, args, &trapResult)) { + return false; + } + } + + // Step 9. + Rooted<Maybe<PropertyDescriptor>> desc(cx); + if (!GetOwnPropertyDescriptor(cx, target, id, &desc)) { + return false; + } + + // Step 10. + if (desc.isSome()) { + // Step 10a. + if (desc->isDataDescriptor() && !desc->configurable() && + !desc->writable()) { + RootedValue value(cx, desc->value()); + bool same; + if (!SameValue(cx, trapResult, value, &same)) { + return false; + } + if (!same) { + return js::Throw(cx, id, JSMSG_MUST_REPORT_SAME_VALUE); + } + } + + // Step 10b. + if (desc->isAccessorDescriptor() && !desc->configurable() && + (desc->getter() == nullptr) && !trapResult.isUndefined()) { + return js::Throw(cx, id, JSMSG_MUST_REPORT_UNDEFINED); + } + } + + // Step 11. + vp.set(trapResult); + return true; +} + +// ES8 rev 0c1bd3004329336774cbc90de727cd0cf5f11e93 +// 9.5.9 Proxy.[[Set]](P, V, Receiver) +bool ScriptedProxyHandler::set(JSContext* cx, HandleObject proxy, HandleId id, + HandleValue v, HandleValue receiver, + ObjectOpResult& result) const { + // Steps 2-4. + RootedObject handler(cx, ScriptedProxyHandler::handlerObject(proxy)); + if (!handler) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, + JSMSG_PROXY_REVOKED); + return false; + } + + // Step 5. + RootedObject target(cx, proxy->as<ProxyObject>().target()); + MOZ_ASSERT(target); + + // Step 6. + RootedValue trap(cx); + if (!GetProxyTrap(cx, handler, cx->names().set, &trap)) { + return false; + } + + // Step 7. + if (trap.isUndefined()) { + return SetProperty(cx, target, id, v, receiver, result); + } + + // Step 8. + RootedValue value(cx); + if (!IdToStringOrSymbol(cx, id, &value)) { + return false; + } + + RootedValue trapResult(cx); + { + FixedInvokeArgs<4> args(cx); + + args[0].setObject(*target); + args[1].set(value); + args[2].set(v); + args[3].set(receiver); + + RootedValue thisv(cx, ObjectValue(*handler)); + if (!Call(cx, trap, thisv, args, &trapResult)) { + return false; + } + } + + // Step 9. + if (!ToBoolean(trapResult)) { + return result.fail(JSMSG_PROXY_SET_RETURNED_FALSE); + } + + // Step 10. + Rooted<Maybe<PropertyDescriptor>> desc(cx); + if (!GetOwnPropertyDescriptor(cx, target, id, &desc)) { + return false; + } + + // Step 11. + if (desc.isSome()) { + // Step 11a. + if (desc->isDataDescriptor() && !desc->configurable() && + !desc->writable()) { + RootedValue value(cx, desc->value()); + bool same; + if (!SameValue(cx, v, value, &same)) { + return false; + } + if (!same) { + return js::Throw(cx, id, JSMSG_CANT_SET_NW_NC); + } + } + + // Step 11b. + if (desc->isAccessorDescriptor() && !desc->configurable() && + desc->setter() == nullptr) { + return js::Throw(cx, id, JSMSG_CANT_SET_WO_SETTER); + } + } + + // Step 12. + return result.succeed(); +} + +// ES7 0c1bd3004329336774cbc90de727cd0cf5f11e93 9.5.13 Proxy.[[Call]] +bool ScriptedProxyHandler::call(JSContext* cx, HandleObject proxy, + const CallArgs& args) const { + // Steps 1-3. + RootedObject handler(cx, ScriptedProxyHandler::handlerObject(proxy)); + if (!handler) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, + JSMSG_PROXY_REVOKED); + return false; + } + + // Step 4. + RootedObject target(cx, proxy->as<ProxyObject>().target()); + MOZ_ASSERT(target); + MOZ_ASSERT(target->isCallable()); + + // Step 5. + RootedValue trap(cx); + if (!GetProxyTrap(cx, handler, cx->names().apply, &trap)) { + return false; + } + + // Step 6. + if (trap.isUndefined()) { + InvokeArgs iargs(cx); + if (!FillArgumentsFromArraylike(cx, iargs, args)) { + return false; + } + + RootedValue fval(cx, ObjectValue(*target)); + return js::Call(cx, fval, args.thisv(), iargs, args.rval()); + } + + // Step 7. + RootedObject argArray(cx, + NewDenseCopiedArray(cx, args.length(), args.array())); + if (!argArray) { + return false; + } + + // Step 8. + FixedInvokeArgs<3> iargs(cx); + + iargs[0].setObject(*target); + iargs[1].set(args.thisv()); + iargs[2].setObject(*argArray); + + RootedValue thisv(cx, ObjectValue(*handler)); + return js::Call(cx, trap, thisv, iargs, args.rval()); +} + +// ES7 0c1bd3004329336774cbc90de727cd0cf5f11e93 9.5.14 Proxy.[[Construct]] +bool ScriptedProxyHandler::construct(JSContext* cx, HandleObject proxy, + const CallArgs& args) const { + // Steps 1-3. + RootedObject handler(cx, ScriptedProxyHandler::handlerObject(proxy)); + if (!handler) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, + JSMSG_PROXY_REVOKED); + return false; + } + + // Step 4. + RootedObject target(cx, proxy->as<ProxyObject>().target()); + MOZ_ASSERT(target); + MOZ_ASSERT(target->isConstructor()); + + // Step 5. + RootedValue trap(cx); + if (!GetProxyTrap(cx, handler, cx->names().construct, &trap)) { + return false; + } + + // Step 6. + if (trap.isUndefined()) { + ConstructArgs cargs(cx); + if (!FillArgumentsFromArraylike(cx, cargs, args)) { + return false; + } + + RootedValue targetv(cx, ObjectValue(*target)); + RootedObject obj(cx); + if (!Construct(cx, targetv, cargs, args.newTarget(), &obj)) { + return false; + } + + args.rval().setObject(*obj); + return true; + } + + // Step 7. + RootedObject argArray(cx, + NewDenseCopiedArray(cx, args.length(), args.array())); + if (!argArray) { + return false; + } + + // Steps 8, 10. + { + FixedInvokeArgs<3> iargs(cx); + + iargs[0].setObject(*target); + iargs[1].setObject(*argArray); + iargs[2].set(args.newTarget()); + + RootedValue thisv(cx, ObjectValue(*handler)); + if (!Call(cx, trap, thisv, iargs, args.rval())) { + return false; + } + } + + // Step 9. + if (!args.rval().isObject()) { + JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, + JSMSG_PROXY_CONSTRUCT_OBJECT); + return false; + } + + return true; +} + +bool ScriptedProxyHandler::nativeCall(JSContext* cx, IsAcceptableThis test, + NativeImpl impl, + const CallArgs& args) const { + ReportIncompatible(cx, args); + return false; +} + +bool ScriptedProxyHandler::getBuiltinClass(JSContext* cx, HandleObject proxy, + ESClass* cls) const { + *cls = ESClass::Other; + return true; +} + +bool ScriptedProxyHandler::isArray(JSContext* cx, HandleObject proxy, + IsArrayAnswer* answer) const { + RootedObject target(cx, proxy->as<ProxyObject>().target()); + if (target) { + return JS::IsArray(cx, target, answer); + } + + *answer = IsArrayAnswer::RevokedProxy; + return true; +} + +const char* ScriptedProxyHandler::className(JSContext* cx, + HandleObject proxy) const { + // Right now the caller is not prepared to handle failures. + return BaseProxyHandler::className(cx, proxy); +} + +JSString* ScriptedProxyHandler::fun_toString(JSContext* cx, HandleObject proxy, + bool isToSource) const { + // The BaseProxyHandler has the desired behavior: Throw for non-callable, + // otherwise return [native code]. + return BaseProxyHandler::fun_toString(cx, proxy, isToSource); +} + +RegExpShared* ScriptedProxyHandler::regexp_toShared(JSContext* cx, + HandleObject proxy) const { + MOZ_CRASH("Should not end up in ScriptedProxyHandler::regexp_toShared"); +} + +bool ScriptedProxyHandler::boxedValue_unbox(JSContext* cx, HandleObject proxy, + MutableHandleValue vp) const { + MOZ_CRASH("Should not end up in ScriptedProxyHandler::boxedValue_unbox"); + return false; +} + +bool ScriptedProxyHandler::isCallable(JSObject* obj) const { + MOZ_ASSERT(obj->as<ProxyObject>().handler() == + &ScriptedProxyHandler::singleton); + uint32_t callConstruct = obj->as<ProxyObject>() + .reservedSlot(IS_CALLCONSTRUCT_EXTRA) + .toPrivateUint32(); + return !!(callConstruct & IS_CALLABLE); +} + +bool ScriptedProxyHandler::isConstructor(JSObject* obj) const { + MOZ_ASSERT(obj->as<ProxyObject>().handler() == + &ScriptedProxyHandler::singleton); + uint32_t callConstruct = obj->as<ProxyObject>() + .reservedSlot(IS_CALLCONSTRUCT_EXTRA) + .toPrivateUint32(); + return !!(callConstruct & IS_CONSTRUCTOR); +} + +const char ScriptedProxyHandler::family = 0; +const ScriptedProxyHandler ScriptedProxyHandler::singleton; + +// ES2021 rev c21b280a2c46e92decf3efeca9e9da35d5b9f622 +// Including the changes from: https://github.com/tc39/ecma262/pull/1814 +// 9.5.14 ProxyCreate. +static bool ProxyCreate(JSContext* cx, CallArgs& args, const char* callerName) { + if (!args.requireAtLeast(cx, callerName, 2)) { + return false; + } + + // Step 1. + RootedObject target(cx, + RequireObjectArg(cx, "`target`", callerName, args[0])); + if (!target) { + return false; + } + + // Step 2. + RootedObject handler(cx, + RequireObjectArg(cx, "`handler`", callerName, args[1])); + if (!handler) { + return false; + } + + // Steps 3-4, 6. + RootedValue priv(cx, ObjectValue(*target)); + JSObject* proxy_ = NewProxyObject(cx, &ScriptedProxyHandler::singleton, priv, + TaggedProto::LazyProto); + if (!proxy_) { + return false; + } + + // Step 7 (reordered). + Rooted<ProxyObject*> proxy(cx, &proxy_->as<ProxyObject>()); + proxy->setReservedSlot(ScriptedProxyHandler::HANDLER_EXTRA, + ObjectValue(*handler)); + + // Step 5. + uint32_t callable = + target->isCallable() ? ScriptedProxyHandler::IS_CALLABLE : 0; + uint32_t constructor = + target->isConstructor() ? ScriptedProxyHandler::IS_CONSTRUCTOR : 0; + proxy->setReservedSlot(ScriptedProxyHandler::IS_CALLCONSTRUCT_EXTRA, + PrivateUint32Value(callable | constructor)); + + // Step 8. + args.rval().setObject(*proxy); + return true; +} + +bool js::proxy(JSContext* cx, unsigned argc, Value* vp) { + CallArgs args = CallArgsFromVp(argc, vp); + + if (!ThrowIfNotConstructing(cx, args, "Proxy")) { + return false; + } + + return ProxyCreate(cx, args, "Proxy"); +} + +static bool RevokeProxy(JSContext* cx, unsigned argc, Value* vp) { + CallArgs args = CallArgsFromVp(argc, vp); + + RootedFunction func(cx, &args.callee().as<JSFunction>()); + RootedObject p(cx, func->getExtendedSlot(ScriptedProxyHandler::REVOKE_SLOT) + .toObjectOrNull()); + + if (p) { + func->setExtendedSlot(ScriptedProxyHandler::REVOKE_SLOT, NullValue()); + + MOZ_ASSERT(p->is<ProxyObject>()); + + p->as<ProxyObject>().setSameCompartmentPrivate(NullValue()); + p->as<ProxyObject>().setReservedSlot(ScriptedProxyHandler::HANDLER_EXTRA, + NullValue()); + } + + args.rval().setUndefined(); + return true; +} + +bool js::proxy_revocable(JSContext* cx, unsigned argc, Value* vp) { + CallArgs args = CallArgsFromVp(argc, vp); + + if (!ProxyCreate(cx, args, "Proxy.revocable")) { + return false; + } + + RootedValue proxyVal(cx, args.rval()); + MOZ_ASSERT(proxyVal.toObject().is<ProxyObject>()); + + RootedFunction revoker( + cx, NewNativeFunction(cx, RevokeProxy, 0, nullptr, + gc::AllocKind::FUNCTION_EXTENDED, GenericObject)); + if (!revoker) { + return false; + } + + revoker->initExtendedSlot(ScriptedProxyHandler::REVOKE_SLOT, proxyVal); + + Rooted<PlainObject*> result(cx, NewPlainObject(cx)); + if (!result) { + return false; + } + + RootedValue revokeVal(cx, ObjectValue(*revoker)); + if (!DefineDataProperty(cx, result, cx->names().proxy, proxyVal) || + !DefineDataProperty(cx, result, cx->names().revoke, revokeVal)) { + return false; + } + + args.rval().setObject(*result); + return true; +} |