/* -*- 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/. */ #include "proxy/ScriptedProxyHandler.h" #include "jsapi.h" #include "vm/Interpreter.h" // For InstanceOfOperator #include "jsobjinlines.h" #include "vm/NativeObject-inl.h" using namespace js; using JS::IsArrayAnswer; using mozilla::ArrayLength; // ES8 rev 0c1bd3004329336774cbc90de727cd0cf5f11e93 // 9.1.6.2 IsCompatiblePropertyDescriptor. BUT that method just calls // 9.1.6.3 ValidateAndApplyPropertyDescriptor with two additional constant // arguments. Therefore step numbering is from the latter method, and // resulting dead code has been removed. static bool IsCompatiblePropertyDescriptor(JSContext* cx, bool extensible, Handle desc, Handle current, bool* bp) { // Step 2. if (!current.object()) { // Step 2a-b,e. As |O| is always undefined, steps 2c-d fall away. *bp = extensible; return true; } // Step 3. if (!desc.hasValue() && !desc.hasWritable() && !desc.hasGetterObject() && !desc.hasSetterObject() && !desc.hasEnumerable() && !desc.hasConfigurable()) { *bp = true; return true; } // Step 4. if ((!desc.hasWritable() || (current.hasWritable() && desc.writable() == current.writable())) && (!desc.hasGetterObject() || desc.getter() == current.getter()) && (!desc.hasSetterObject() || desc.setter() == current.setter()) && (!desc.hasEnumerable() || desc.enumerable() == current.enumerable()) && (!desc.hasConfigurable() || desc.configurable() == current.configurable())) { if (!desc.hasValue()) { *bp = true; return true; } bool same = false; if (!SameValue(cx, desc.value(), current.value(), &same)) return false; if (same) { *bp = true; return true; } } // Step 5. if (!current.configurable()) { // Step 5a. if (desc.hasConfigurable() && desc.configurable()) { *bp = false; return true; } // Step 5b. if (desc.hasEnumerable() && desc.enumerable() != current.enumerable()) { *bp = false; return true; } } // Step 6. if (desc.isGenericDescriptor()) { *bp = true; return true; } // Step 7. if (current.isDataDescriptor() != desc.isDataDescriptor()) { // Steps 7a, 11. As |O| is always undefined, steps 2b-c fall away. *bp = current.configurable(); return true; } // Step 8. if (current.isDataDescriptor()) { MOZ_ASSERT(desc.isDataDescriptor()); // by step 7 if (!current.configurable() && !current.writable()) { if (desc.hasWritable() && desc.writable()) { *bp = false; return true; } if (desc.hasValue()) { bool same; if (!SameValue(cx, desc.value(), current.value(), &same)) return false; if (!same) { *bp = false; return true; } } } *bp = true; return true; } // Step 9. MOZ_ASSERT(current.isAccessorDescriptor()); // by step 8 MOZ_ASSERT(desc.isAccessorDescriptor()); // by step 7 *bp = (current.configurable() || ((!desc.hasSetterObject() || desc.setter() == current.setter()) && (!desc.hasGetterObject() || desc.getter() == current.getter()))); return true; } // Get the [[ProxyHandler]] of a scripted proxy. /* static */ JSObject* ScriptedProxyHandler::handlerObject(const JSObject* proxy) { MOZ_ASSERT(proxy->as().handler() == &ScriptedProxyHandler::singleton); return proxy->as().extra(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, HandlePropertyName 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)) { JSAutoByteString bytes(cx, name); if (!bytes) return false; JS_ReportErrorNumberLatin1(cx, GetErrorMessage, nullptr, JSMSG_BAD_TRAP, bytes.ptr()); 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().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().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().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().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().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 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().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()) { JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_PROXY_GETOWN_OBJORUNDEF); return false; } // Step 10. Rooted targetDesc(cx); if (!GetOwnPropertyDescriptor(cx, target, id, &targetDesc)) return false; // Step 11. if (trapResult.isUndefined()) { // Step 11a. if (!targetDesc.object()) { desc.object().set(nullptr); return true; } // Step 11b. if (!targetDesc.configurable()) { JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_CANT_REPORT_NC_AS_NE); return false; } // Steps 11c-d. bool extensibleTarget; if (!IsExtensible(cx, target, &extensibleTarget)) return false; // Step 11e. if (!extensibleTarget) { JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_CANT_REPORT_E_AS_NE); return false; } // Step 11f. desc.object().set(nullptr); return true; } // Step 12. bool extensibleTarget; if (!IsExtensible(cx, target, &extensibleTarget)) return false; // Step 13. Rooted resultDesc(cx); if (!ToPropertyDescriptor(cx, trapResult, true, &resultDesc)) return false; // Step 14. CompletePropertyDescriptor(&resultDesc); // Step 15. bool valid; if (!IsCompatiblePropertyDescriptor(cx, extensibleTarget, resultDesc, targetDesc, &valid)) return false; // Step 16. if (!valid) { JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_CANT_REPORT_INVALID); return false; } // Step 17. if (!resultDesc.configurable()) { if (!targetDesc.object()) { JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_CANT_REPORT_NE_AS_NC); return false; } if (targetDesc.configurable()) { JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_CANT_REPORT_C_AS_NC); return false; } } // Step 18. desc.set(resultDesc); desc.object().set(proxy); return true; } // ES8 rev 0c1bd3004329336774cbc90de727cd0cf5f11e93 9.5.6 Proxy.[[DefineOwnProperty]](P, Desc) bool ScriptedProxyHandler::defineProperty(JSContext* cx, HandleObject proxy, HandleId id, Handle 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().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 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.object()) { // Step 15a. if (!extensibleTarget) { JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_CANT_DEFINE_NEW); return false; } // Step 15b. if (settingConfigFalse) { JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_CANT_DEFINE_NE_AS_NC); return false; } } else { // Steps 16a-b. bool valid; if (!IsCompatiblePropertyDescriptor(cx, extensibleTarget, desc, targetDesc, &valid)) return false; if (!valid || (settingConfigFalse && targetDesc.configurable())) { JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_CANT_DEFINE_INVALID); return false; } } // 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, AutoIdVector& props) { // Step 2. RootedObject obj(cx, NonNullObject(cx, v)); if (!obj) return false; // Step 3. uint32_t len; if (!GetLengthProperty(cx, obj, &len)) return false; // Steps 4-6. RootedValue next(cx); RootedId id(cx); uint32_t index = 0; while (index < len) { // Steps 6a-b. if (!GetElement(cx, obj, obj, index, &next)) return false; // Step 6c. if (!next.isString() && !next.isSymbol()) { JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_ONWKEYS_STR_SYM); return false; } if (!ValueToId(cx, next, &id)) return false; // Step 6d. if (!props.append(id)) return false; // Step 6e. index++; } // Step 7. return true; } // ES8 rev 0c1bd3004329336774cbc90de727cd0cf5f11e93 9.5.11 Proxy.[[OwnPropertyKeys]]() bool ScriptedProxyHandler::ownPropertyKeys(JSContext* cx, HandleObject proxy, AutoIdVector& 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().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. AutoIdVector trapResult(cx); if (!CreateFilteredListFromArrayLike(cx, trapResultArray, trapResult)) return false; // Step 9. bool extensibleTarget; if (!IsExtensible(cx, target, &extensibleTarget)) return false; // Steps 10-11. AutoIdVector targetKeys(cx); if (!GetPropertyKeys(cx, target, JSITER_OWNONLY | JSITER_HIDDEN | JSITER_SYMBOLS, &targetKeys)) return false; // Steps 12-13. AutoIdVector targetConfigurableKeys(cx); AutoIdVector targetNonconfigurableKeys(cx); // Step 14. Rooted desc(cx); for (size_t i = 0; i < targetKeys.length(); ++i) { // Step 14a. if (!GetOwnPropertyDescriptor(cx, target, targetKeys[i], &desc)) return false; // Steps 14b-c. if (desc.object() && !desc.configurable()) { if (!targetNonconfigurableKeys.append(targetKeys[i])) return false; } else { if (!targetConfigurableKeys.append(targetKeys[i])) return false; } } // Step 15. if (extensibleTarget && targetNonconfigurableKeys.empty()) return props.appendAll(trapResult); // Step 16. // The algorithm below always removes all occurences of the same key // at once, so we can use a set here. Rooted> uncheckedResultKeys(cx, GCHashSet(cx)); if (!uncheckedResultKeys.init(trapResult.length())) return false; for (size_t i = 0, len = trapResult.length(); i < len; i++) { MOZ_ASSERT(!JSID_IS_VOID(trapResult[i])); if (!uncheckedResultKeys.put(trapResult[i])) return false; } // Step 17. for (size_t i = 0; i < targetNonconfigurableKeys.length(); ++i) { MOZ_ASSERT(!JSID_IS_VOID(targetNonconfigurableKeys[i])); auto ptr = uncheckedResultKeys.lookup(targetNonconfigurableKeys[i]); // Step 17a. if (!ptr) { JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_CANT_SKIP_NC); return false; } // Step 17b. uncheckedResultKeys.remove(ptr); } // Step 18. if (extensibleTarget) return props.appendAll(trapResult); // Step 19. for (size_t i = 0; i < targetConfigurableKeys.length(); ++i) { MOZ_ASSERT(!JSID_IS_VOID(targetConfigurableKeys[i])); auto ptr = uncheckedResultKeys.lookup(targetConfigurableKeys[i]); // Step 19a. if (!ptr) { JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_CANT_REPORT_E_AS_NE); return false; } // Step 19b. uncheckedResultKeys.remove(ptr); } // Step 20. if (!uncheckedResultKeys.empty()) { JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_CANT_REPORT_NEW); return false; } // Step 21. return props.appendAll(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().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 desc(cx); if (!GetOwnPropertyDescriptor(cx, target, id, &desc)) return false; // Step 12. if (desc.object() && !desc.configurable()) { RootedValue v(cx, IdToValue(id)); ReportValueError(cx, JSMSG_CANT_DELETE, JSDVG_IGNORE_STACK, v, nullptr); return false; } // Steps 11,13. 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().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 desc(cx); if (!GetOwnPropertyDescriptor(cx, target, id, &desc)) return false; // Step 9b. if (desc.object()) { // Step 9b(i). if (!desc.configurable()) { JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_CANT_REPORT_NC_AS_NE); return false; } // Step 9b(ii). bool extensible; if (!IsExtensible(cx, target, &extensible)) return false; // Step 9b(iii). if (!extensible) { JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_CANT_REPORT_E_AS_NE); return false; } } } // 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().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 desc(cx); if (!GetOwnPropertyDescriptor(cx, target, id, &desc)) return false; // Step 10. if (desc.object()) { // Step 10a. if (desc.isDataDescriptor() && !desc.configurable() && !desc.writable()) { bool same; if (!SameValue(cx, trapResult, desc.value(), &same)) return false; if (!same) { JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_MUST_REPORT_SAME_VALUE); return false; } } // Step 10b. if (desc.isAccessorDescriptor() && !desc.configurable() && desc.getterObject() == nullptr) { if (!trapResult.isUndefined()) { JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_MUST_REPORT_UNDEFINED); return false; } } } // 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().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 desc(cx); if (!GetOwnPropertyDescriptor(cx, target, id, &desc)) return false; // Step 11. if (desc.object()) { // Step 11a. if (desc.isDataDescriptor() && !desc.configurable() && !desc.writable()) { bool same; if (!SameValue(cx, v, desc.value(), &same)) return false; if (!same) { JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_CANT_SET_NW_NC); return false; } } // Step 11b. if (desc.isAccessorDescriptor() && !desc.configurable() && desc.setterObject() == nullptr) { JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_CANT_SET_WO_SETTER); return false; } } // 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().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().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::hasInstance(JSContext* cx, HandleObject proxy, MutableHandleValue v, bool* bp) const { return InstanceOfOperator(cx, proxy, v, bp); } 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().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, unsigned indent) const { JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_INCOMPATIBLE_PROTO, js_Function_str, js_toString_str, "object"); return nullptr; } bool ScriptedProxyHandler::regexp_toShared(JSContext* cx, HandleObject proxy, RegExpGuard* g) const { MOZ_CRASH("Should not end up in ScriptedProxyHandler::regexp_toShared"); return false; } 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().handler() == &ScriptedProxyHandler::singleton); uint32_t callConstruct = obj->as().extra(IS_CALLCONSTRUCT_EXTRA).toPrivateUint32(); return !!(callConstruct & IS_CALLABLE); } bool ScriptedProxyHandler::isConstructor(JSObject* obj) const { MOZ_ASSERT(obj->as().handler() == &ScriptedProxyHandler::singleton); uint32_t callConstruct = obj->as().extra(IS_CALLCONSTRUCT_EXTRA).toPrivateUint32(); return !!(callConstruct & IS_CONSTRUCTOR); } const char ScriptedProxyHandler::family = 0; const ScriptedProxyHandler ScriptedProxyHandler::singleton; bool IsRevokedScriptedProxy(JSObject* obj) { obj = CheckedUnwrap(obj); return obj && IsScriptedProxy(obj) && !obj->as().target(); } // ES8 rev 0c1bd3004329336774cbc90de727cd0cf5f11e93 9.5.14 ProxyCreate. static bool ProxyCreate(JSContext* cx, CallArgs& args, const char* callerName) { if (args.length() < 2) { JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_MORE_ARGS_NEEDED, callerName, "1", "s"); return false; } // Step 1. RootedObject target(cx, NonNullObject(cx, args[0])); if (!target) return false; // Step 2. if (IsRevokedScriptedProxy(target)) { JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_PROXY_ARG_REVOKED, "1"); return false; } // Step 3. RootedObject handler(cx, NonNullObject(cx, args[1])); if (!handler) return false; // Step 4. if (IsRevokedScriptedProxy(handler)) { JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_PROXY_ARG_REVOKED, "2"); return false; } // Steps 5-6, 8. RootedValue priv(cx, ObjectValue(*target)); JSObject* proxy_ = NewProxyObject(cx, &ScriptedProxyHandler::singleton, priv, TaggedProto::LazyProto); if (!proxy_) return false; // Step 9 (reordered). Rooted proxy(cx, &proxy_->as()); proxy->setExtra(ScriptedProxyHandler::HANDLER_EXTRA, ObjectValue(*handler)); // Step 7. uint32_t callable = target->isCallable() ? ScriptedProxyHandler::IS_CALLABLE : 0; uint32_t constructor = target->isConstructor() ? ScriptedProxyHandler::IS_CONSTRUCTOR : 0; proxy->setExtra(ScriptedProxyHandler::IS_CALLCONSTRUCT_EXTRA, PrivateUint32Value(callable | constructor)); // Step 10. 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()); RootedObject p(cx, func->getExtendedSlot(ScriptedProxyHandler::REVOKE_SLOT).toObjectOrNull()); if (p) { func->setExtendedSlot(ScriptedProxyHandler::REVOKE_SLOT, NullValue()); MOZ_ASSERT(p->is()); p->as().setSameCompartmentPrivate(NullValue()); p->as().setExtra(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()); RootedObject revoker(cx, NewFunctionByIdWithReserved(cx, RevokeProxy, 0, 0, AtomToId(cx->names().revoke))); if (!revoker) return false; revoker->as().initExtendedSlot(ScriptedProxyHandler::REVOKE_SLOT, proxyVal); RootedPlainObject result(cx, NewBuiltinClassInstance(cx)); if (!result) return false; RootedValue revokeVal(cx, ObjectValue(*revoker)); if (!DefineProperty(cx, result, cx->names().proxy, proxyVal) || !DefineProperty(cx, result, cx->names().revoke, revokeVal)) { return false; } args.rval().setObject(*result); return true; }