|
| 1 | +// Adapted from SES/Caja - Copyright (C) 2011 Google Inc. |
| 2 | +// Copyright (C) 2018 Agoric |
| 3 | + |
| 4 | +// Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | +// you may not use this file except in compliance with the License. |
| 6 | +// You may obtain a copy of the License at |
| 7 | +// |
| 8 | +// http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | +// |
| 10 | +// Unless required by applicable law or agreed to in writing, software |
| 11 | +// distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | +// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | +// See the License for the specific language governing permissions and |
| 14 | +// limitations under the License. |
| 15 | +// SPDX-License-Identifier: MIT |
| 16 | + |
| 17 | +// based upon: |
| 18 | +// https://github.com/google/caja/blob/master/src/com/google/caja/ses/startSES.js |
| 19 | +// https://github.com/google/caja/blob/master/src/com/google/caja/ses/repairES5.js |
| 20 | +// https://github.com/tc39/proposal-frozen-realms/blob/91ac390e3451da92b5c27e354b39e52b7636a437/shim/src/deep-freeze.js |
| 21 | + |
| 22 | +/* global WebAssembly, SharedArrayBuffer, console */ |
| 23 | +'use strict'; |
| 24 | +module.exports = function() { |
| 25 | + |
| 26 | + const intrinsics = [ |
| 27 | + // Anonymous Intrinsics |
| 28 | + // ThrowTypeError |
| 29 | + Object.getOwnPropertyDescriptor(Function.prototype, 'caller').get, |
| 30 | + // IteratorPrototype |
| 31 | + Object.getPrototypeOf( |
| 32 | + Object.getPrototypeOf(new Array()[Symbol.iterator]()) |
| 33 | + ), |
| 34 | + // ArrayIteratorPrototype |
| 35 | + Object.getPrototypeOf(new Array()[Symbol.iterator]()), |
| 36 | + // StringIteratorPrototype |
| 37 | + Object.getPrototypeOf(new String()[Symbol.iterator]()), |
| 38 | + // MapIteratorPrototype |
| 39 | + Object.getPrototypeOf(new Map()[Symbol.iterator]()), |
| 40 | + // SetIteratorPrototype |
| 41 | + Object.getPrototypeOf(new Set()[Symbol.iterator]()), |
| 42 | + // GeneratorFunction |
| 43 | + Object.getPrototypeOf(function* () {}), |
| 44 | + // AsyncFunction |
| 45 | + Object.getPrototypeOf(async function() {}), |
| 46 | + // AsyncGeneratorFunction |
| 47 | + Object.getPrototypeOf(async function* () {}), |
| 48 | + // TypedArray |
| 49 | + Object.getPrototypeOf(Uint8Array), |
| 50 | + |
| 51 | + // 18 The Global Object |
| 52 | + eval, |
| 53 | + isFinite, |
| 54 | + isNaN, |
| 55 | + parseFloat, |
| 56 | + parseInt, |
| 57 | + decodeURI, |
| 58 | + decodeURIComponent, |
| 59 | + encodeURI, |
| 60 | + encodeURIComponent, |
| 61 | + |
| 62 | + // 19 Fundamental Objects |
| 63 | + Object, // 19.1 |
| 64 | + Function, // 19.2 |
| 65 | + Boolean, // 19.3 |
| 66 | + Symbol, // 19.4 |
| 67 | + |
| 68 | + // Disabled pending stack trace mutation handling |
| 69 | + // Error, // 19.5 |
| 70 | + // EvalError, |
| 71 | + // RangeError, |
| 72 | + // ReferenceError, |
| 73 | + // SyntaxError, |
| 74 | + // TypeError, |
| 75 | + // URIError, |
| 76 | + |
| 77 | + // 20 Numbers and Dates |
| 78 | + Number, // 20.1 |
| 79 | + Math, // 20.2 |
| 80 | + Date, // 20.3 |
| 81 | + |
| 82 | + // 21 Text Processing |
| 83 | + String, // 21.1 |
| 84 | + RegExp, // 21.2 |
| 85 | + |
| 86 | + // 22 Indexed Collections |
| 87 | + Array, // 22.1 |
| 88 | + |
| 89 | + Int8Array, |
| 90 | + Uint8Array, |
| 91 | + Uint8ClampedArray, |
| 92 | + Int16Array, |
| 93 | + Uint16Array, |
| 94 | + Int32Array, |
| 95 | + Uint32Array, |
| 96 | + Float32Array, |
| 97 | + Float64Array, |
| 98 | + BigInt64Array, |
| 99 | + BigUint64Array, |
| 100 | + |
| 101 | + // 23 Keyed Collections |
| 102 | + Map, // 23.1 |
| 103 | + Set, // 23.2 |
| 104 | + WeakMap, // 23.3 |
| 105 | + WeakSet, // 23.4 |
| 106 | + |
| 107 | + // 24 Structured Data |
| 108 | + ArrayBuffer, // 24.1 |
| 109 | + DataView, // 24.3 |
| 110 | + JSON, // 24.5 |
| 111 | + Promise, // 25.4 |
| 112 | + |
| 113 | + // 26 Reflection |
| 114 | + Reflect, // 26.1 |
| 115 | + Proxy, // 26.2 |
| 116 | + |
| 117 | + // B.2.1 |
| 118 | + escape, |
| 119 | + unescape, |
| 120 | + |
| 121 | + // Web compatibility |
| 122 | + clearImmediate, |
| 123 | + clearInterval, |
| 124 | + clearTimeout, |
| 125 | + decodeURI, |
| 126 | + decodeURIComponent, |
| 127 | + encodeURI, |
| 128 | + encodeURIComponent, |
| 129 | + setImmediate, |
| 130 | + setInterval, |
| 131 | + setTimeout, |
| 132 | + |
| 133 | + // Other APIs |
| 134 | + console, |
| 135 | + BigInt, |
| 136 | + Atomics, |
| 137 | + WebAssembly, |
| 138 | + SharedArrayBuffer |
| 139 | + ]; |
| 140 | + |
| 141 | + if (typeof Intl !== 'undefined') |
| 142 | + intrinsics.push(Intl); |
| 143 | + |
| 144 | + intrinsics.forEach(deepFreeze); |
| 145 | + |
| 146 | + function deepFreeze(root) { |
| 147 | + |
| 148 | + const { freeze, getOwnPropertyDescriptors, getPrototypeOf } = Object; |
| 149 | + const { ownKeys } = Reflect; |
| 150 | + |
| 151 | + // Objects that are deeply frozen. |
| 152 | + // It turns out that Error is reachable from WebAssembly so it is |
| 153 | + // explicitly added here to ensure it is not frozen |
| 154 | + const frozenSet = new WeakSet([Error, Error.prototype]); |
| 155 | + |
| 156 | + /** |
| 157 | + * "innerDeepFreeze()" acts like "Object.freeze()", except that: |
| 158 | + * |
| 159 | + * To deepFreeze an object is to freeze it and all objects transitively |
| 160 | + * reachable from it via transitive reflective property and prototype |
| 161 | + * traversal. |
| 162 | + */ |
| 163 | + function innerDeepFreeze(node) { |
| 164 | + // Objects that we have frozen in this round. |
| 165 | + const freezingSet = new Set(); |
| 166 | + |
| 167 | + // If val is something we should be freezing but aren't yet, |
| 168 | + // add it to freezingSet. |
| 169 | + function enqueue(val) { |
| 170 | + if (Object(val) !== val) { |
| 171 | + // ignore primitives |
| 172 | + return; |
| 173 | + } |
| 174 | + const type = typeof val; |
| 175 | + if (type !== 'object' && type !== 'function') { |
| 176 | + // NB: handle for any new cases in future |
| 177 | + } |
| 178 | + if (frozenSet.has(val) || freezingSet.has(val)) { |
| 179 | + // todo use uncurried form |
| 180 | + // Ignore if already frozen or freezing |
| 181 | + return; |
| 182 | + } |
| 183 | + freezingSet.add(val); // todo use uncurried form |
| 184 | + } |
| 185 | + |
| 186 | + function doFreeze(obj) { |
| 187 | + // Immediately freeze the object to ensure reactive |
| 188 | + // objects such as proxies won't add properties |
| 189 | + // during traversal, before they get frozen. |
| 190 | + |
| 191 | + // Object are verified before being enqueued, |
| 192 | + // therefore this is a valid candidate. |
| 193 | + // Throws if this fails (strict mode). |
| 194 | + freeze(obj); |
| 195 | + |
| 196 | + // We rely upon certain commitments of Object.freeze and proxies here |
| 197 | + |
| 198 | + // Get stable/immutable outbound links before a Proxy has a chance to do |
| 199 | + // something sneaky. |
| 200 | + const proto = getPrototypeOf(obj); |
| 201 | + const descs = getOwnPropertyDescriptors(obj); |
| 202 | + enqueue(proto); |
| 203 | + ownKeys(descs).forEach((name) => { |
| 204 | + // todo uncurried form |
| 205 | + // todo: getOwnPropertyDescriptors is guaranteed to return well-formed |
| 206 | + // descriptors, but they still inherit from Object.prototype. If |
| 207 | + // someone has poisoned Object.prototype to add 'value' or 'get' |
| 208 | + // properties, then a simple 'if ("value" in desc)' or 'desc.value' |
| 209 | + // test could be confused. We use hasOwnProperty to be sure about |
| 210 | + // whether 'value' is present or not, which tells us for sure that |
| 211 | + // this is a data property. |
| 212 | + const desc = descs[name]; |
| 213 | + if ('value' in desc) { |
| 214 | + // todo uncurried form |
| 215 | + enqueue(desc.value); |
| 216 | + } else { |
| 217 | + enqueue(desc.get); |
| 218 | + enqueue(desc.set); |
| 219 | + } |
| 220 | + }); |
| 221 | + } |
| 222 | + |
| 223 | + function dequeue() { |
| 224 | + // New values added before forEach() has finished will be visited. |
| 225 | + freezingSet.forEach(doFreeze); // todo curried forEach |
| 226 | + } |
| 227 | + |
| 228 | + function commit() { |
| 229 | + // todo curried forEach |
| 230 | + // we capture the real WeakSet.prototype.add above, in case someone |
| 231 | + // changes it. The two-argument form of forEach passes the second |
| 232 | + // argument as the 'this' binding, so we add to the correct set. |
| 233 | + freezingSet.forEach(frozenSet.add, frozenSet); |
| 234 | + } |
| 235 | + |
| 236 | + enqueue(node); |
| 237 | + dequeue(); |
| 238 | + commit(); |
| 239 | + } |
| 240 | + |
| 241 | + innerDeepFreeze(root); |
| 242 | + return root; |
| 243 | + } |
| 244 | +}; |
0 commit comments