closure-builder
Version:
Simple Closure, Soy and JavaScript Build system
529 lines (482 loc) • 20.4 kB
JavaScript
// Copyright 2013 The Closure Library Authors. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS-IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
/**
* @fileoverview The TrustedResourceUrl type and its builders.
*
* TODO(xtof): Link to document stating type contract.
*/
goog.provide('goog.html.TrustedResourceUrl');
goog.require('goog.asserts');
goog.require('goog.html.trustedtypes');
goog.require('goog.i18n.bidi.Dir');
goog.require('goog.i18n.bidi.DirectionalString');
goog.require('goog.string.Const');
goog.require('goog.string.TypedString');
/**
* A URL which is under application control and from which script, CSS, and
* other resources that represent executable code, can be fetched.
*
* Given that the URL can only be constructed from strings under application
* control and is used to load resources, bugs resulting in a malformed URL
* should not have a security impact and are likely to be easily detectable
* during testing. Given the wide number of non-RFC compliant URLs in use,
* stricter validation could prevent some applications from being able to use
* this type.
*
* Instances of this type must be created via the factory method,
* (`fromConstant`, `fromConstants`, `format` or
* `formatWithParams`), and not by invoking its constructor. The constructor
* intentionally takes no parameters and the type is immutable; hence only a
* default instance corresponding to the empty string can be obtained via
* constructor invocation.
*
* @see goog.html.TrustedResourceUrl#fromConstant
* @constructor
* @final
* @struct
* @implements {goog.i18n.bidi.DirectionalString}
* @implements {goog.string.TypedString}
*/
goog.html.TrustedResourceUrl = function() {
/**
* The contained value of this TrustedResourceUrl. The field has a purposely
* ugly name to make (non-compiled) code that attempts to directly access this
* field stand out.
* @private {!TrustedScriptURL|string}
*/
this.privateDoNotAccessOrElseTrustedResourceUrlWrappedValue_ = '';
/**
* Value stored as TrustedURL. TrustedResourceURL corresponds to TrustedURL in
* some context thus we need to store it separately.
* @private {?TrustedURL}
*/
this.trustedURL_ = null;
/**
* A type marker used to implement additional run-time type checking.
* @see goog.html.TrustedResourceUrl#unwrap
* @const {!Object}
* @private
*/
this.TRUSTED_RESOURCE_URL_TYPE_MARKER_GOOG_HTML_SECURITY_PRIVATE_ =
goog.html.TrustedResourceUrl.TYPE_MARKER_GOOG_HTML_SECURITY_PRIVATE_;
};
/**
* @override
* @const
*/
goog.html.TrustedResourceUrl.prototype.implementsGoogStringTypedString = true;
/**
* Returns this TrustedResourceUrl's value as a string.
*
* IMPORTANT: In code where it is security relevant that an object's type is
* indeed `TrustedResourceUrl`, use
* `goog.html.TrustedResourceUrl.unwrap` instead of this method. If in
* doubt, assume that it's security relevant. In particular, note that
* goog.html functions which return a goog.html type do not guarantee that
* the returned instance is of the right type. For example:
*
* <pre>
* var fakeSafeHtml = new String('fake');
* fakeSafeHtml.__proto__ = goog.html.SafeHtml.prototype;
* var newSafeHtml = goog.html.SafeHtml.htmlEscape(fakeSafeHtml);
* // newSafeHtml is just an alias for fakeSafeHtml, it's passed through by
* // goog.html.SafeHtml.htmlEscape() as fakeSafeHtml instanceof
* // goog.html.SafeHtml.
* </pre>
*
* @see goog.html.TrustedResourceUrl#unwrap
* @override
*/
goog.html.TrustedResourceUrl.prototype.getTypedStringValue = function() {
return this.privateDoNotAccessOrElseTrustedResourceUrlWrappedValue_
.toString();
};
/**
* @override
* @const
*/
goog.html.TrustedResourceUrl.prototype.implementsGoogI18nBidiDirectionalString =
true;
/**
* Returns this URLs directionality, which is always `LTR`.
* @override
*/
goog.html.TrustedResourceUrl.prototype.getDirection = function() {
return goog.i18n.bidi.Dir.LTR;
};
/**
* Creates a new TrustedResourceUrl with params added to URL. Both search and
* hash params can be specified.
*
* @param {string|?Object<string, *>|undefined} searchParams Search parameters
* to add to URL. See goog.html.TrustedResourceUrl.stringifyParams_ for
* exact format definition.
* @param {(string|?Object<string, *>)=} opt_hashParams Hash parameters to add
* to URL. See goog.html.TrustedResourceUrl.stringifyParams_ for exact
* format definition.
* @return {!goog.html.TrustedResourceUrl} New TrustedResourceUrl with params.
*/
goog.html.TrustedResourceUrl.prototype.cloneWithParams = function(
searchParams, opt_hashParams) {
var url = goog.html.TrustedResourceUrl.unwrap(this);
var parts = goog.html.TrustedResourceUrl.URL_PARAM_PARSER_.exec(url);
var urlBase = parts[1];
var urlSearch = parts[2] || '';
var urlHash = parts[3] || '';
return goog.html.TrustedResourceUrl
.createTrustedResourceUrlSecurityPrivateDoNotAccessOrElse(
urlBase +
goog.html.TrustedResourceUrl.stringifyParams_(
'?', urlSearch, searchParams) +
goog.html.TrustedResourceUrl.stringifyParams_(
'#', urlHash, opt_hashParams));
};
if (goog.DEBUG) {
/**
* Returns a debug string-representation of this value.
*
* To obtain the actual string value wrapped in a TrustedResourceUrl, use
* `goog.html.TrustedResourceUrl.unwrap`.
*
* @see goog.html.TrustedResourceUrl#unwrap
* @override
*/
goog.html.TrustedResourceUrl.prototype.toString = function() {
return 'TrustedResourceUrl{' +
this.privateDoNotAccessOrElseTrustedResourceUrlWrappedValue_ + '}';
};
}
/**
* Performs a runtime check that the provided object is indeed a
* TrustedResourceUrl object, and returns its value.
*
* @param {!goog.html.TrustedResourceUrl} trustedResourceUrl The object to
* extract from.
* @return {string} The trustedResourceUrl object's contained string, unless
* the run-time type check fails. In that case, `unwrap` returns an
* innocuous string, or, if assertions are enabled, throws
* `goog.asserts.AssertionError`.
*/
goog.html.TrustedResourceUrl.unwrap = function(trustedResourceUrl) {
return goog.html.TrustedResourceUrl.unwrapTrustedScriptURL(trustedResourceUrl)
.toString();
};
/**
* Unwraps value as TrustedScriptURL if supported or as a string if not.
* @param {!goog.html.TrustedResourceUrl} trustedResourceUrl
* @return {!TrustedScriptURL|string}
* @see goog.html.TrustedResourceUrl.unwrap
*/
goog.html.TrustedResourceUrl.unwrapTrustedScriptURL = function(
trustedResourceUrl) {
// Perform additional Run-time type-checking to ensure that
// trustedResourceUrl is indeed an instance of the expected type. This
// provides some additional protection against security bugs due to
// application code that disables type checks.
// Specifically, the following checks are performed:
// 1. The object is an instance of the expected type.
// 2. The object is not an instance of a subclass.
// 3. The object carries a type marker for the expected type. "Faking" an
// object requires a reference to the type marker, which has names intended
// to stand out in code reviews.
if (trustedResourceUrl instanceof goog.html.TrustedResourceUrl &&
trustedResourceUrl.constructor === goog.html.TrustedResourceUrl &&
trustedResourceUrl
.TRUSTED_RESOURCE_URL_TYPE_MARKER_GOOG_HTML_SECURITY_PRIVATE_ ===
goog.html.TrustedResourceUrl
.TYPE_MARKER_GOOG_HTML_SECURITY_PRIVATE_) {
return trustedResourceUrl
.privateDoNotAccessOrElseTrustedResourceUrlWrappedValue_;
} else {
goog.asserts.fail('expected object of type TrustedResourceUrl, got \'' +
trustedResourceUrl + '\' of type ' + goog.typeOf(trustedResourceUrl));
return 'type_error:TrustedResourceUrl';
}
};
/**
* Unwraps value as TrustedURL if supported or as a string if not.
* @param {!goog.html.TrustedResourceUrl} trustedResourceUrl
* @return {!TrustedURL|string}
* @see goog.html.TrustedResourceUrl.unwrap
*/
goog.html.TrustedResourceUrl.unwrapTrustedURL = function(trustedResourceUrl) {
return trustedResourceUrl.trustedURL_ ?
trustedResourceUrl.trustedURL_ :
goog.html.TrustedResourceUrl.unwrap(trustedResourceUrl);
};
/**
* Creates a TrustedResourceUrl from a format string and arguments.
*
* The arguments for interpolation into the format string map labels to values.
* Values of type `goog.string.Const` are interpolated without modifcation.
* Values of other types are cast to string and encoded with
* encodeURIComponent.
*
* `%{<label>}` markers are used in the format string to indicate locations
* to be interpolated with the valued mapped to the given label. `<label>`
* must contain only alphanumeric and `_` characters.
*
* The format string must start with one of the following:
* - `https://<origin>/`
* - `//<origin>/`
* - `/<pathStart>`
* - `about:blank#`
*
* `<origin>` must contain only alphanumeric or any of the following: `-.:[]`.
* `<pathStart>` is any character except `/` and `\`.
*
* Example usage:
*
* var url = goog.html.TrustedResourceUrl.format(goog.string.Const.from(
* 'https://www.google.com/search?q=%{query}'), {'query': searchTerm});
*
* var url = goog.html.TrustedResourceUrl.format(goog.string.Const.from(
* '//www.youtube.com/v/%{videoId}?hl=en&fs=1%{autoplay}'), {
* 'videoId': videoId,
* 'autoplay': opt_autoplay ?
* goog.string.Const.from('&autoplay=1') : goog.string.Const.EMPTY
* });
*
* While this function can be used to create a TrustedResourceUrl from only
* constants, fromConstant() and fromConstants() are generally preferable for
* that purpose.
*
* @param {!goog.string.Const} format The format string.
* @param {!Object<string, (string|number|!goog.string.Const)>} args Mapping
* of labels to values to be interpolated into the format string.
* goog.string.Const values are interpolated without encoding.
* @return {!goog.html.TrustedResourceUrl}
* @throws {!Error} On an invalid format string or if a label used in the
* the format string is not present in args.
*/
goog.html.TrustedResourceUrl.format = function(format, args) {
var formatStr = goog.string.Const.unwrap(format);
if (!goog.html.TrustedResourceUrl.BASE_URL_.test(formatStr)) {
throw new Error('Invalid TrustedResourceUrl format: ' + formatStr);
}
var result = formatStr.replace(
goog.html.TrustedResourceUrl.FORMAT_MARKER_, function(match, id) {
if (!Object.prototype.hasOwnProperty.call(args, id)) {
throw new Error(
'Found marker, "' + id + '", in format string, "' + formatStr +
'", but no valid label mapping found ' +
'in args: ' + JSON.stringify(args));
}
var arg = args[id];
if (arg instanceof goog.string.Const) {
return goog.string.Const.unwrap(arg);
} else {
return encodeURIComponent(String(arg));
}
});
return goog.html.TrustedResourceUrl
.createTrustedResourceUrlSecurityPrivateDoNotAccessOrElse(result);
};
/**
* @private @const {!RegExp}
*/
goog.html.TrustedResourceUrl.FORMAT_MARKER_ = /%{(\w+)}/g;
/**
* The URL must be absolute, scheme-relative or path-absolute. So it must
* start with:
* - https:// followed by allowed origin characters.
* - // followed by allowed origin characters.
* - Any absolute or relative path.
*
* Based on
* https://url.spec.whatwg.org/commit-snapshots/56b74ce7cca8883eab62e9a12666e2fac665d03d/#url-parsing
* an initial / which is not followed by another / or \ will end up in the "path
* state" and from there it can only go to "fragment state" and "query state".
*
* We don't enforce a well-formed domain name. So '.' or '1.2' are valid.
* That's ok because the origin comes from a compile-time constant.
*
* A regular expression is used instead of goog.uri for several reasons:
* - Strictness. E.g. we don't want any userinfo component and we don't
* want '/./, nor \' in the first path component.
* - Small trusted base. goog.uri is generic and might need to change,
* reasoning about all the ways it can parse a URL now and in the future
* is error-prone.
* - Code size. We expect many calls to .format(), many of which might
* not be using goog.uri.
* - Simplicity. Using goog.uri would likely not result in simpler nor shorter
* code.
* @private @const {!RegExp}
*/
goog.html.TrustedResourceUrl.BASE_URL_ = new RegExp(
'^((https:)?//[0-9a-z.:[\\]-]+/' // Origin.
+ '|/[^/\\\\]' // Absolute path.
+ '|[^:/\\\\%]+/' // Relative path.
+ '|[^:/\\\\%]*[?#]' // Query string or fragment.
+ '|about:blank#' // about:blank with fragment.
+ ')',
'i');
/**
* RegExp for splitting a URL into the base, search field, and hash field.
*
* @private @const {!RegExp}
*/
goog.html.TrustedResourceUrl.URL_PARAM_PARSER_ =
/^([^?#]*)(\?[^#]*)?(#[\s\S]*)?/;
/**
* Formats the URL same as TrustedResourceUrl.format and then adds extra URL
* parameters.
*
* Example usage:
*
* // Creates '//www.youtube.com/v/abc?autoplay=1' for videoId='abc' and
* // opt_autoplay=1. Creates '//www.youtube.com/v/abc' for videoId='abc'
* // and opt_autoplay=undefined.
* var url = goog.html.TrustedResourceUrl.formatWithParams(
* goog.string.Const.from('//www.youtube.com/v/%{videoId}'),
* {'videoId': videoId},
* {'autoplay': opt_autoplay});
*
* @param {!goog.string.Const} format The format string.
* @param {!Object<string, (string|number|!goog.string.Const)>} args Mapping
* of labels to values to be interpolated into the format string.
* goog.string.Const values are interpolated without encoding.
* @param {string|?Object<string, *>|undefined} searchParams Parameters to add
* to URL. See goog.html.TrustedResourceUrl.stringifyParams_ for exact
* format definition.
* @param {(string|?Object<string, *>)=} opt_hashParams Hash parameters to add
* to URL. See goog.html.TrustedResourceUrl.stringifyParams_ for exact
* format definition.
* @return {!goog.html.TrustedResourceUrl}
* @throws {!Error} On an invalid format string or if a label used in the
* the format string is not present in args.
*/
goog.html.TrustedResourceUrl.formatWithParams = function(
format, args, searchParams, opt_hashParams) {
var url = goog.html.TrustedResourceUrl.format(format, args);
return url.cloneWithParams(searchParams, opt_hashParams);
};
/**
* Creates a TrustedResourceUrl object from a compile-time constant string.
*
* Compile-time constant strings are inherently program-controlled and hence
* trusted.
*
* @param {!goog.string.Const} url A compile-time-constant string from which to
* create a TrustedResourceUrl.
* @return {!goog.html.TrustedResourceUrl} A TrustedResourceUrl object
* initialized to `url`.
*/
goog.html.TrustedResourceUrl.fromConstant = function(url) {
return goog.html.TrustedResourceUrl
.createTrustedResourceUrlSecurityPrivateDoNotAccessOrElse(
goog.string.Const.unwrap(url));
};
/**
* Creates a TrustedResourceUrl object from a compile-time constant strings.
*
* Compile-time constant strings are inherently program-controlled and hence
* trusted.
*
* @param {!Array<!goog.string.Const>} parts Compile-time-constant strings from
* which to create a TrustedResourceUrl.
* @return {!goog.html.TrustedResourceUrl} A TrustedResourceUrl object
* initialized to concatenation of `parts`.
*/
goog.html.TrustedResourceUrl.fromConstants = function(parts) {
var unwrapped = '';
for (var i = 0; i < parts.length; i++) {
unwrapped += goog.string.Const.unwrap(parts[i]);
}
return goog.html.TrustedResourceUrl
.createTrustedResourceUrlSecurityPrivateDoNotAccessOrElse(unwrapped);
};
/**
* Type marker for the TrustedResourceUrl type, used to implement additional
* run-time type checking.
* @const {!Object}
* @private
*/
goog.html.TrustedResourceUrl.TYPE_MARKER_GOOG_HTML_SECURITY_PRIVATE_ = {};
/**
* Package-internal utility method to create TrustedResourceUrl instances.
*
* @param {string} url The string to initialize the TrustedResourceUrl object
* with.
* @return {!goog.html.TrustedResourceUrl} The initialized TrustedResourceUrl
* object.
* @package
*/
goog.html.TrustedResourceUrl
.createTrustedResourceUrlSecurityPrivateDoNotAccessOrElse = function(url) {
var trustedResourceUrl = new goog.html.TrustedResourceUrl();
trustedResourceUrl.privateDoNotAccessOrElseTrustedResourceUrlWrappedValue_ =
goog.html.trustedtypes.PRIVATE_DO_NOT_ACCESS_OR_ELSE_POLICY ?
goog.html.trustedtypes.PRIVATE_DO_NOT_ACCESS_OR_ELSE_POLICY
.createScriptURL(url) :
url;
if (goog.html.trustedtypes.PRIVATE_DO_NOT_ACCESS_OR_ELSE_POLICY) {
trustedResourceUrl.trustedURL_ =
goog.html.trustedtypes.PRIVATE_DO_NOT_ACCESS_OR_ELSE_POLICY.createURL(
url);
}
return trustedResourceUrl;
};
/**
* Stringifies the passed params to be used as either a search or hash field of
* a URL.
*
* @param {string} prefix The prefix character for the given field ('?' or '#').
* @param {string} currentString The existing field value (including the prefix
* character, if the field is present).
* @param {string|?Object<string, *>|undefined} params The params to set or
* append to the field.
* - If `undefined` or `null`, the field remains unchanged.
* - If a string, then the string will be escaped and the field will be
* overwritten with that value.
* - If an Object, that object is treated as a set of key-value pairs to be
* appended to the current field. Note that JavaScript doesn't guarantee the
* order of values in an object which might result in non-deterministic order
* of the parameters. However, browsers currently preserve the order. The
* rules for each entry:
* - If an array, it will be processed as if each entry were an additional
* parameter with exactly the same key, following the same logic below.
* - If `undefined` or `null`, it will be skipped.
* - Otherwise, it will be turned into a string, escaped, and appended.
* @return {string}
* @private
*/
goog.html.TrustedResourceUrl.stringifyParams_ = function(
prefix, currentString, params) {
if (params == null) {
// Do not modify the field.
return currentString;
}
if (goog.isString(params)) {
// Set field to the passed string.
return params ? prefix + encodeURIComponent(params) : '';
}
// Add on parameters to field from key-value object.
for (var key in params) {
var value = params[key];
var outputValues = goog.isArray(value) ? value : [value];
for (var i = 0; i < outputValues.length; i++) {
var outputValue = outputValues[i];
if (outputValue != null) {
if (!currentString) {
currentString = prefix;
}
currentString += (currentString.length > prefix.length ? '&' : '') +
encodeURIComponent(key) + '=' +
encodeURIComponent(String(outputValue));
}
}
}
return currentString;
};