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|
'use strict';
const {
ArrayIsArray,
Map,
MapPrototypeSet,
ObjectCreate,
ObjectEntries,
ObjectFreeze,
ObjectKeys,
ObjectSetPrototypeOf,
RegExpPrototypeTest,
SafeMap,
SafeSet,
Symbol,
uncurryThis,
} = primordials;
const {
canBeRequiredByUsers
} = require('internal/bootstrap/loaders').NativeModule;
const {
ERR_MANIFEST_ASSERT_INTEGRITY,
ERR_MANIFEST_INTEGRITY_MISMATCH,
ERR_MANIFEST_INVALID_RESOURCE_FIELD,
ERR_MANIFEST_UNKNOWN_ONERROR,
} = require('internal/errors').codes;
let debug = require('internal/util/debuglog').debuglog('policy', (fn) => {
debug = fn;
});
const SRI = require('internal/policy/sri');
const crypto = require('crypto');
const { Buffer } = require('buffer');
const { URL } = require('internal/url');
const { createHash, timingSafeEqual } = crypto;
const HashUpdate = uncurryThis(crypto.Hash.prototype.update);
const HashDigest = uncurryThis(crypto.Hash.prototype.digest);
const BufferToString = uncurryThis(Buffer.prototype.toString);
const kRelativeURLStringPattern = /^\.{0,2}\//;
const { getOptionValue } = require('internal/options');
const shouldAbortOnUncaughtException =
getOptionValue('--abort-on-uncaught-exception');
const { abort, exit, _rawDebug } = process;
// From https://url.spec.whatwg.org/#special-scheme
const SPECIAL_SCHEMES = new SafeSet([
'file:',
'ftp:',
'http:',
'https:',
'ws:',
'wss:',
]);
const kCascade = Symbol('cascade');
function REACTION_THROW(error) {
throw error;
}
function REACTION_EXIT(error) {
REACTION_LOG(error);
if (shouldAbortOnUncaughtException) {
abort();
}
exit(1);
}
function REACTION_LOG(error) {
_rawDebug(error.stack);
}
/**
* @typedef {(specifier: string) => true | URL} DependencyMapper
* @typedef {Record<string, string> | true} DependencyMap
* @typedef {true | string | SRI[]} Integrity
*/
class Manifest {
/**
* @type {Map<string, DependencyMapper>}
*
* Used to compare a resource to the content body at the resource.
* `true` is used to signify that all integrities are allowed, otherwise,
* SRI strings are parsed to compare with the body.
*
* Separate from #resourceDependencies due to conflicts with things like
* `blob:` being both a scope and a resource potentially as well as
* `file:` being parsed to `file:///` instead of remaining host neutral.
*/
#scopeDependencies = new SafeMap();
/**
* @type {Map<string, true | null | 'cascade'>}
*
* Used to allow arbitrary loading within a scope
*/
#scopeIntegrities = new SafeMap();
/**
* @type {Map<string, Integrity>}
*
* Used to compare a resource to the content body at the resource.
* `true` is used to signify that all integrities are allowed, otherwise,
* SRI strings are parsed to compare with the body.
*
* This stores strings instead of eagerly parsing SRI strings
* and only converts them to SRI data structures when needed.
* This avoids needing to parse all SRI strings at startup even
* if some never end up being used.
*/
#resourceIntegrities = new SafeMap();
/**
* @type {Map<string, DependencyMapper>}
*
* Used to find where a dependency is located.
*
* This stores functions to lazily calculate locations as needed.
* `true` is used to signify that the location is not specified
* by the manifest and default resolution should be allowed.
*
* The functions return `null` to signify that a dependency is
* not found
*/
#resourceDependencies = new SafeMap();
/**
* @type {(err: Error) => void}
*
* Performs default action for what happens when a manifest encounters
* a violation such as abort()ing or exiting the process, throwing the error,
* or logging the error.
*/
#reaction = null;
/**
* `obj` should match the policy file format described in the docs
* it is expected to not have prototype pollution issues either by reassigning
* the prototype to `null` for values or by running prior to any user code.
*
* `manifestURL` is a URL to resolve relative locations against.
*
* @param {object} obj
* @param {string} manifestURL
*/
constructor(obj, manifestURL) {
const scopes = this.#scopeDependencies;
const integrities = this.#resourceIntegrities;
const dependencies = this.#resourceDependencies;
let reaction = REACTION_THROW;
if (obj.onerror) {
const behavior = obj.onerror;
if (behavior === 'throw') {
} else if (behavior === 'exit') {
reaction = REACTION_EXIT;
} else if (behavior === 'log') {
reaction = REACTION_LOG;
} else {
throw new ERR_MANIFEST_UNKNOWN_ONERROR(behavior);
}
}
this.#reaction = reaction;
const jsonResourcesEntries = ObjectEntries(obj.resources ?? {});
const jsonScopesEntries = ObjectEntries(obj.scopes ?? {});
function searchDependencies(resourceHREF, target, conditions) {
if (
target &&
typeof target === 'object' &&
!ArrayIsArray(target)
) {
const keys = ObjectKeys(target);
for (let i = 0; i < keys.length; i++) {
const key = keys[i];
if (conditions.has(key)) {
const ret = searchDependencies(
resourceHREF,
target[key],
conditions);
if (ret != null) {
return ret;
}
}
}
} else if (typeof target === 'string') {
return target;
} else if (target === true) {
return target;
} else {
throw new ERR_MANIFEST_INVALID_RESOURCE_FIELD(
resourceHREF,
'dependencies');
}
return null;
}
/**
* @param {string} resourceHREF
* @param {{[key: string]: string | true}} dependencyMap
* @param {boolean} cascade
* @returns {DependencyMapper}
*/
const createDependencyMapper = (
resourceHREF,
dependencyMap,
cascade
) => {
let parentDeps;
return (toSpecifier, conditions) => {
if (toSpecifier in dependencyMap !== true) {
if (cascade === true) {
let scopeHREF;
if (typeof parentDeps === 'undefined') {
do {
scopeHREF = this.#findScopeHREF(resourceHREF);
} while (
scopeHREF !== null &&
scopes.has(scopeHREF) !== true
);
}
if (scopeHREF === null) {
parentDeps = () => null;
} else {
parentDeps = scopes.get(scopeHREF);
}
return parentDeps(toSpecifier);
}
return null;
}
const to = searchDependencies(
resourceHREF,
dependencyMap[toSpecifier],
conditions);
if (to === true) {
return true;
}
if (parsedURLs.has(to)) {
return parsedURLs.get(to);
} else if (canBeRequiredByUsers(to)) {
const href = `node:${to}`;
const resolvedURL = new URL(href);
parsedURLs.set(to, resolvedURL);
parsedURLs.set(href, resolvedURL);
return resolvedURL;
} else if (RegExpPrototypeTest(kRelativeURLStringPattern, to)) {
const resolvedURL = new URL(to, manifestURL);
const href = resourceHREF;
parsedURLs.set(to, resolvedURL);
parsedURLs.set(href, resolvedURL);
return resolvedURL;
}
const resolvedURL = new URL(to);
const href = resourceHREF;
parsedURLs.set(to, resolvedURL);
parsedURLs.set(href, resolvedURL);
return resolvedURL;
};
};
/**
* Stores URLs keyed by string specifier relative to the manifest
* @type {Map<string, URL>}
*/
const parsedURLs = new SafeMap();
/**
* Resolves a valid url string against the manifest
* @param {string} originalHREF
* @returns {string}
*/
const resolve = (originalHREF) => {
if (parsedURLs.has(originalHREF)) {
return parsedURLs.get(originalHREF).href;
} else if (
RegExpPrototypeTest(kRelativeURLStringPattern, originalHREF)
) {
const resourceURL = new URL(originalHREF, manifestURL);
const resourceHREF = resourceURL.href;
parsedURLs.set(originalHREF, resourceURL);
parsedURLs.set(resourceURL.href, resourceURL);
return resourceHREF;
}
const resourceURL = new URL(originalHREF);
const resourceHREF = resourceURL.href;
parsedURLs.set(originalHREF, resourceURL);
return resourceHREF;
};
/**
* @param {string} resourceHREF
* @param {DependencyMap} dependencyMap
* @param {boolean} cascade
* @param {Map<string, DependencyMapper>} store
*/
const insertDependencyMap = (
resourceHREF,
dependencyMap,
cascade,
store
) => {
if (cascade !== undefined && typeof cascade !== 'boolean') {
throw new ERR_MANIFEST_INVALID_RESOURCE_FIELD(
resourceHREF,
'cascade');
}
if (dependencyMap === null || dependencyMap === undefined) {
dependencyMap = ObjectCreate(null);
}
if (
typeof dependencyMap === 'object' &&
!ArrayIsArray(dependencyMap)
) {
const dependencyRedirectList = createDependencyMapper(
resourceHREF,
dependencyMap,
cascade);
store.set(resourceHREF, dependencyRedirectList);
return;
} else if (dependencyMap === true) {
const arbitraryDependencies = /** @type {()=>true} */() => true;
store.set(resourceHREF, arbitraryDependencies);
return;
}
throw new ERR_MANIFEST_INVALID_RESOURCE_FIELD(
resourceHREF,
'dependencies');
};
/**
* Does a special allowance for scopes to be non-valid URLs
* that are only protocol strings
* @param {string} resourceHREF
* @returns {string}
*/
const protocolOrResolve = (resourceHREF) => {
if (resourceHREF.endsWith(':')) {
// URL parse will trim these anyway, save the compute
resourceHREF = resourceHREF.replace(
// eslint-disable-next-line
/^[\x00-\x1F\x20]|\x09\x0A\x0D|[\x00-\x1F\x20]$/g,
''
);
if (/^[a-zA-Z][a-zA-Z+\-.]*:$/.test(resourceHREF)) {
return resourceHREF;
}
}
return resolve(resourceHREF);
};
for (let i = 0; i < jsonResourcesEntries.length; i++) {
const [originalHREF, resourceDescriptor] = jsonResourcesEntries[i];
const cascade = resourceDescriptor.cascade;
const dependencyMap = resourceDescriptor.dependencies;
const resourceHREF = resolve(originalHREF);
const integrity = resourceDescriptor.integrity;
if (typeof integrity !== 'undefined') {
debug('Manifest contains integrity for resource %s', originalHREF);
if (integrities.has(resourceHREF)) {
if (integrities.get(resourceHREF) !== integrity) {
throw new ERR_MANIFEST_INTEGRITY_MISMATCH(resourceHREF);
}
}
if (typeof integrity === 'string') {
integrities.set(resourceHREF, integrity);
} else if (integrity === true) {
integrities.set(resourceHREF, true);
} else {
throw new ERR_MANIFEST_INVALID_RESOURCE_FIELD(
resourceHREF,
'integrity');
}
} else {
integrities.set(resourceHREF, cascade ? kCascade : null);
}
insertDependencyMap(resourceHREF, dependencyMap, cascade, dependencies);
}
const scopeIntegrities = this.#scopeIntegrities;
for (let i = 0; i < jsonScopesEntries.length; i++) {
const [originalHREF, scopeDescriptor] = jsonScopesEntries[i];
const integrity = scopeDescriptor.integrity;
const cascade = scopeDescriptor.cascade;
const dependencyMap = scopeDescriptor.dependencies;
const resourceHREF = protocolOrResolve(originalHREF);
if (typeof integrity !== 'undefined') {
debug('Manifest contains integrity for scope %s', originalHREF);
if (scopeIntegrities.has(resourceHREF)) {
if (scopeIntegrities.get(resourceHREF) !== integrity) {
throw new ERR_MANIFEST_INTEGRITY_MISMATCH(resourceHREF);
}
}
if (integrity === true) {
scopeIntegrities.set(resourceHREF, true);
} else {
throw new ERR_MANIFEST_INVALID_RESOURCE_FIELD(
resourceHREF,
'integrity');
}
} else {
scopeIntegrities.set(resourceHREF, cascade ? kCascade : null);
}
insertDependencyMap(resourceHREF, dependencyMap, cascade, scopes);
}
ObjectFreeze(this);
}
/**
* Finds the longest key within `this.#scopeDependencies` that covers a
* specific HREF
* @param {string} href
* @returns {null | string}
*/
#findScopeHREF = (href) => {
let currentURL = new URL(href);
let protocol = currentURL.protocol;
// Non-opaque blobs adopt origins
if (protocol === 'blob:' && currentURL.origin !== 'null') {
currentURL = new URL(currentURL.origin);
protocol = currentURL.protocol;
}
// Only a few schemes are hierarchical
if (SPECIAL_SCHEMES.has(currentURL.protocol)) {
// Make first '..' act like '.'
if (currentURL.pathname.slice(-1) !== '/') {
currentURL.pathname += '/';
}
let lastHREF;
let currentHREF = currentURL.href;
do {
if (this.#scopeDependencies.has(currentHREF)) {
return currentHREF;
}
lastHREF = currentHREF;
currentURL = new URL('..', currentURL);
currentHREF = currentURL.href;
} while (lastHREF !== currentHREF);
}
if (this.#scopeDependencies.has(protocol)) {
return protocol;
}
return null;
}
#createResolver = (resolve) => {
return {
resolve: (to, conditions) => resolve(`${to}`, conditions),
reaction: this.#reaction
};
}
/**
* @param {string} requester
*/
getDependencyMapper(requester) {
const requesterHREF = `${requester}`;
const dependencies = this.#resourceDependencies;
if (dependencies.has(requesterHREF)) {
return this.#createResolver(
dependencies.get(requesterHREF) ||
(() => null)
);
}
const scopes = this.#scopeDependencies;
if (scopes.size !== 0) {
const scopeHREF = this.#findScopeHREF(requesterHREF);
if (typeof scopeHREF === 'string') {
return this.#createResolver(scopes.get(scopeHREF));
}
}
return this.#createResolver(() => null);
}
assertIntegrity(url, content) {
const href = `${url}`;
debug('Checking integrity of %s', href);
const realIntegrities = new Map();
const integrities = this.#resourceIntegrities;
function processEntry(href) {
let integrityEntries = integrities.get(href);
if (integrityEntries === true) return true;
if (typeof integrityEntries === 'string') {
const sri = ObjectFreeze(SRI.parse(integrityEntries));
integrities.set(href, sri);
integrityEntries = sri;
}
return integrityEntries;
}
if (integrities.has(href)) {
const integrityEntries = processEntry(href);
if (integrityEntries === true) return true;
if (ArrayIsArray(integrityEntries)) {
// Avoid clobbered Symbol.iterator
for (let i = 0; i < integrityEntries.length; i++) {
const {
algorithm,
value: expected
} = integrityEntries[i];
const hash = createHash(algorithm);
HashUpdate(hash, content);
const digest = HashDigest(hash);
if (digest.length === expected.length &&
timingSafeEqual(digest, expected)) {
return true;
}
MapPrototypeSet(
realIntegrities,
algorithm,
BufferToString(digest, 'base64')
);
}
}
if (integrityEntries !== kCascade) {
const error = new ERR_MANIFEST_ASSERT_INTEGRITY(url, realIntegrities);
this.#reaction(error);
}
}
let scope = this.#findScopeHREF(href);
while (scope !== null) {
if (this.#scopeIntegrities.has(scope)) {
const entry = this.#scopeIntegrities.get(scope);
if (entry === true) {
return true;
} else if (entry === kCascade) {
} else {
break;
}
}
const nextScope = this.#findScopeHREF(new URL('..', scope));
if (!nextScope || nextScope === scope) {
break;
}
scope = nextScope;
}
const error = new ERR_MANIFEST_ASSERT_INTEGRITY(url, realIntegrities);
this.#reaction(error);
}
}
// Lock everything down to avoid problems even if reference is leaked somehow
ObjectSetPrototypeOf(Manifest, null);
ObjectSetPrototypeOf(Manifest.prototype, null);
ObjectFreeze(Manifest);
ObjectFreeze(Manifest.prototype);
module.exports = ObjectFreeze({ Manifest });
|