/* 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/. */
/*
* Manifest.sys.mjs is the top level api for managing installed web applications
*
https://www.w3.org/TR/appmanifest/
*
* It is used to trigger the installation of a web application via .install()
* and to access the manifest data (including icons).
*
* TODO:
* - Trigger appropriate app installed events
*/
import { ManifestObtainer } from "resource://gre/modules/ManifestObtainer.sys.mjs";
import { ManifestIcons } from "resource://gre/modules/ManifestIcons.sys.mjs";
const lazy = {};
ChromeUtils.defineESModuleGetters(lazy, {
JSONFile: "resource://gre/modules/JSONFile.sys.mjs",
});
/**
* Generates an hash for the given string.
*
* @note The generated hash is returned in base64 form. Mind the fact base64
* is case-sensitive if you are going to reuse this code.
*/
function generateHash(aString, hashAlg) {
const cryptoHash = Cc["@mozilla.org/security/hash;1"].createInstance(
Ci.nsICryptoHash
);
cryptoHash.init(hashAlg);
const stringStream = Cc[
"@mozilla.org/io/string-input-stream;1"
].createInstance(Ci.nsIStringInputStream);
stringStream.setByteStringData(aString);
cryptoHash.updateFromStream(stringStream, -1);
// base64 allows the '/' char, but we can't use it for filenames.
return cryptoHash.finish(true).replace(/\//g, "-");
}
/**
* Trims the query parameters from a url
*/
function stripQuery(url) {
return url.split("?")[0];
}
// Folder in which we store the manifest files
const MANIFESTS_DIR = PathUtils.join(PathUtils.profileDir, "manifests");
// We maintain a list of scopes for installed webmanifests so we can determine
// whether a given url is within the scope of a previously installed manifest
const MANIFESTS_FILE = "manifest-scopes.json";
/**
* Manifest object
*/
class Manifest {
constructor(browser, manifestUrl) {
this._manifestUrl = manifestUrl;
// The key for this is the manifests URL that is required to be unique.
// However arbitrary urls are not safe file paths so lets hash it.
const filename =
generateHash(manifestUrl, Ci.nsICryptoHash.SHA256) + ".json";
this._path = PathUtils.join(MANIFESTS_DIR, filename);
this.browser = browser;
}
/**
* See Bug 1871109
* This function is called at the beginning of initialize() to check if a given
* manifest has MD5 based filename, if so we remove it and migrate the content to
* a new file with SHA256 based name.
* This is done due to security concern, as MD5 is an outdated hashing algorithm and
* shouldn't be used anymore
*/
async removeMD5BasedFilename() {
const filenameMD5 =
generateHash(this._manifestUrl, Ci.nsICryptoHash.MD5) + ".json";
const MD5Path = PathUtils.join(MANIFESTS_DIR, filenameMD5);
try {
await IOUtils.copy(MD5Path, this._path, { noOverwrite: true });
} catch (error) {
// we are ignoring the failures returned from copy as it should not stop us from
// installing a new manifest
}
// Remove the old MD5 based file unconditionally to ensure it's no longer used
try {
await IOUtils.remove(MD5Path);
} catch {
// ignore the error in case MD5 based file does not exist
}
}
get browser() {
return this._browser;
}
set browser(aBrowser) {
this._browser = aBrowser;
}
async initialize() {
await this.removeMD5BasedFilename();
this._store = new lazy.JSONFile({ path: this._path, saveDelayMs: 100 });
await this._store.load();
}
async prefetch(browser) {
const manifestData = await ManifestObtainer.browserObtainManifest(browser);
const icon = await ManifestIcons.browserFetchIcon(
browser,
manifestData,
192
);
const data = {
installed: false,
manifest: manifestData,
cached_icon: icon,
};
return data;
}
async install() {
const manifestData = await ManifestObtainer.browserObtainManifest(
this._browser
);
this._store.data = {
installed: true,
manifest: manifestData,
};
Manifests.manifestInstalled(this);
this._store.saveSoon();
}
async icon(expectedSize) {
if ("cached_icon" in this._store.data) {
return this._store.data.cached_icon;
}
const icon = await ManifestIcons.browserFetchIcon(
this._browser,
this._store.data.manifest,
expectedSize
);
// Cache the icon so future requests do not go over the network
this._store.data.cached_icon = icon;
this._store.saveSoon();
return icon;
}
get scope() {
const scope =
this._store.data.manifest.scope || this._store.data.manifest.start_url;
return stripQuery(scope);
}
get name() {
return (
this._store.data.manifest.short_name ||
this._store.data.manifest.name ||
this._store.data.manifest.short_url
);
}
get url() {
return this._manifestUrl;
}
get installed() {
return (this._store.data && this._store.data.installed) || false;
}
get start_url() {
return this._store.data.manifest.start_url;
}
get path() {
return this._path;
}
}
/*
* Manifests maintains the list of installed manifests
*/
export var Manifests = {
async _initialize() {
if (this._readyPromise) {
return this._readyPromise;
}
// Prevent multiple initializations
this._readyPromise = (async () => {
// Make sure the manifests have the folder needed to save into
await IOUtils.makeDirectory(MANIFESTS_DIR, { ignoreExisting: true });
// Ensure any existing scope data we have about manifests is loaded
this._path = PathUtils.join(PathUtils.profileDir, MANIFESTS_FILE);
this._store = new lazy.JSONFile({ path: this._path });
await this._store.load();
// If we don't have any existing data, initialize empty
if (!this._store.data.hasOwnProperty("scopes")) {
this._store.data.scopes = new Map();
}
})();
// Cache the Manifest objects creates as they are references to files
// and we do not want multiple file handles
this.manifestObjs = new Map();
return this._readyPromise;
},
// When a manifest is installed, we save its scope so we can determine if
// future visits fall within this manifests scope
manifestInstalled(manifest) {
this._store.data.scopes[manifest.scope] = manifest.url;
this._store.saveSoon();
},
// Given a url, find if it is within an installed manifests scope and if so
// return that manifests url
findManifestUrl(url) {
for (let scope in this._store.data.scopes) {
if (url.startsWith(scope)) {
return this._store.data.scopes[scope];
}
}
return null;
},
// Get the manifest given a url, or if not look for a manifest that is
// tied to the current page
async getManifest(browser, manifestUrl) {
// Ensure we have all started up
if (!this._readyPromise) {
await this._initialize();
}
// If the client does not already know its manifestUrl, we take the
// url of the client and see if it matches the scope of any installed
// manifests
if (!manifestUrl) {
const url = stripQuery(browser.currentURI.spec);
manifestUrl = this.findManifestUrl(url);
}
// No matches so no manifest
if (manifestUrl === null) {
return null;
}
// If we have already created this manifest return cached
if (this.manifestObjs.has(manifestUrl)) {
const manifest = this.manifestObjs.get(manifestUrl);
if (manifest.browser !== browser) {
manifest.browser = browser;
}
return manifest;
}
// Otherwise create a new manifest object
const manifest = new Manifest(browser, manifestUrl);
this.manifestObjs.set(manifestUrl, manifest);
await manifest.initialize();
return manifest;
},
};
