1 files changed, 467 insertions, 0 deletions
diff --git a/toolkit/mozapps/webextensions/internal/ProductAddonChecker.jsm b/toolkit/mozapps/webextensions/internal/ProductAddonChecker.jsm
new file mode 100644
index 000000000..f98dd2a94
--- /dev/null
+++ b/toolkit/mozapps/webextensions/internal/ProductAddonChecker.jsm
@@ -0,0 +1,467 @@
+/* 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/. */
+
+"use strict";
+
+const { classes: Cc, interfaces: Ci, utils: Cu } = Components;
+
+const LOCAL_EME_SOURCES = [{
+  "id": "gmp-eme-adobe",
+  "src": "chrome://global/content/gmp-sources/eme-adobe.json"
+}, {
+  "id": "gmp-gmpopenh264",
+  "src": "chrome://global/content/gmp-sources/openh264.json"
+}, {
+  "id": "gmp-widevinecdm",
+  "src": "chrome://global/content/gmp-sources/widevinecdm.json"
+}];
+
+this.EXPORTED_SYMBOLS = [ "ProductAddonChecker" ];
+
+Cu.importGlobalProperties(["XMLHttpRequest"]);
+
+Cu.import("resource://gre/modules/XPCOMUtils.jsm");
+Cu.import("resource://gre/modules/Services.jsm");
+Cu.import("resource://gre/modules/Task.jsm");
+Cu.import("resource://gre/modules/Log.jsm");
+Cu.import("resource://gre/modules/CertUtils.jsm");
+/* globals checkCert, BadCertHandler*/
+Cu.import("resource://gre/modules/FileUtils.jsm");
+Cu.import("resource://gre/modules/NetUtil.jsm");
+Cu.import("resource://gre/modules/osfile.jsm");
+
+/* globals GMPPrefs */
+XPCOMUtils.defineLazyModuleGetter(this, "GMPPrefs",
+                                  "resource://gre/modules/GMPUtils.jsm");
+
+/* globals OS */
+
+XPCOMUtils.defineLazyModuleGetter(this, "UpdateUtils",
+                                  "resource://gre/modules/UpdateUtils.jsm");
+
+XPCOMUtils.defineLazyModuleGetter(this, "ServiceRequest",
+                                  "resource://gre/modules/ServiceRequest.jsm");
+
+// This exists so that tests can override the XHR behaviour for downloading
+// the addon update XML file.
+var CreateXHR = function() {
+  return Cc["@mozilla.org/xmlextras/xmlhttprequest;1"].
+  createInstance(Ci.nsISupports);
+}
+
+var logger = Log.repository.getLogger("addons.productaddons");
+
+/**
+ * Number of milliseconds after which we need to cancel `downloadXML`.
+ *
+ * Bug 1087674 suggests that the XHR we use in `downloadXML` may
+ * never terminate in presence of network nuisances (e.g. strange
+ * antivirus behavior). This timeout is a defensive measure to ensure
+ * that we fail cleanly in such case.
+ */
+const TIMEOUT_DELAY_MS = 20000;
+// Chunk size for the incremental downloader
+const DOWNLOAD_CHUNK_BYTES_SIZE = 300000;
+// Incremental downloader interval
+const DOWNLOAD_INTERVAL  = 0;
+// How much of a file to read into memory at a time for hashing
+const HASH_CHUNK_SIZE = 8192;
+
+/**
+ * Gets the status of an XMLHttpRequest either directly or from its underlying
+ * channel.
+ *
+ * @param  request
+ *         The XMLHttpRequest.
+ * @return an integer status value.
+ */
+function getRequestStatus(request) {
+  let status = null;
+  try {
+    status = request.status;
+  }
+  catch (e) {
+  }
+
+  if (status != null) {
+    return status;
+  }
+
+  return request.channel.QueryInterface(Ci.nsIRequest).status;
+}
+
+/**
+ * Downloads an XML document from a URL optionally testing the SSL certificate
+ * for certain attributes.
+ *
+ * @param  url
+ *         The url to download from.
+ * @param  allowNonBuiltIn
+ *         Whether to trust SSL certificates without a built-in CA issuer.
+ * @param  allowedCerts
+ *         The list of certificate attributes to match the SSL certificate
+ *         against or null to skip checks.
+ * @return a promise that resolves to the DOM document downloaded or rejects
+ *         with a JS exception in case of error.
+ */
+function downloadXML(url, allowNonBuiltIn = false, allowedCerts = null) {
+  return new Promise((resolve, reject) => {
+    let request = CreateXHR();
+    // This is here to let unit test code override XHR
+    if (request.wrappedJSObject) {
+      request = request.wrappedJSObject;
+    }
+    request.open("GET", url, true);
+    request.channel.notificationCallbacks = new BadCertHandler(allowNonBuiltIn);
+    // Prevent the request from reading from the cache.
+    request.channel.loadFlags |= Ci.nsIRequest.LOAD_BYPASS_CACHE;
+    // Prevent the request from writing to the cache.
+    request.channel.loadFlags |= Ci.nsIRequest.INHIBIT_CACHING;
+    // Use conservative TLS settings. See bug 1325501.
+    // TODO move to ServiceRequest.
+    if (request.channel instanceof Ci.nsIHttpChannelInternal) {
+      request.channel.QueryInterface(Ci.nsIHttpChannelInternal).beConservative = true;
+    }
+    request.timeout = TIMEOUT_DELAY_MS;
+
+    request.overrideMimeType("text/xml");
+    // The Cache-Control header is only interpreted by proxies and the
+    // final destination. It does not help if a resource is already
+    // cached locally.
+    request.setRequestHeader("Cache-Control", "no-cache");
+    // HTTP/1.0 servers might not implement Cache-Control and
+    // might only implement Pragma: no-cache
+    request.setRequestHeader("Pragma", "no-cache");
+
+    let fail = (event) => {
+      let request = event.target;
+      let status = getRequestStatus(request);
+      let message = "Failed downloading XML, status: " + status +  ", reason: " + event.type;
+      logger.warn(message);
+      let ex = new Error(message);
+      ex.status = status;
+      reject(ex);
+    };
+
+    let success = (event) => {
+      logger.info("Completed downloading document");
+      let request = event.target;
+
+      try {
+        checkCert(request.channel, allowNonBuiltIn, allowedCerts);
+      } catch (ex) {
+        logger.error("Request failed certificate checks: " + ex);
+        ex.status = getRequestStatus(request);
+        reject(ex);
+        return;
+      }
+
+      resolve(request.responseXML);
+    };
+
+    request.addEventListener("error", fail, false);
+    request.addEventListener("abort", fail, false);
+    request.addEventListener("timeout", fail, false);
+    request.addEventListener("load", success, false);
+
+    logger.info("sending request to: " + url);
+    request.send(null);
+  });
+}
+
+function downloadJSON(uri) {
+  logger.info("fetching config from: " + uri);
+  return new Promise((resolve, reject) => {
+    let xmlHttp = new ServiceRequest({mozAnon: true});
+
+    xmlHttp.onload = function(aResponse) {
+      resolve(JSON.parse(this.responseText));
+    };
+
+    xmlHttp.onerror = function(e) {
+      reject("Fetching " + uri + " results in error code: " + e.target.status);
+    };
+
+    xmlHttp.open("GET", uri);
+    xmlHttp.overrideMimeType("application/json");
+    xmlHttp.send();
+  });
+}
+
+
+/**
+ * Parses a list of add-ons from a DOM document.
+ *
+ * @param  document
+ *         The DOM document to parse.
+ * @return null if there is no <addons> element otherwise an object containing
+ *         an array of the addons listed and a field notifying whether the
+ *         fallback was used.
+ */
+function parseXML(document) {
+  // Check that the root element is correct
+  if (document.documentElement.localName != "updates") {
+    throw new Error("got node name: " + document.documentElement.localName +
+                    ", expected: updates");
+  }
+
+  // Check if there are any addons elements in the updates element
+  let addons = document.querySelector("updates:root > addons");
+  if (!addons) {
+    return null;
+  }
+
+  let results = [];
+  let addonList = document.querySelectorAll("updates:root > addons > addon");
+  for (let addonElement of addonList) {
+    let addon = {};
+
+    for (let name of ["id", "URL", "hashFunction", "hashValue", "version", "size"]) {
+      if (addonElement.hasAttribute(name)) {
+        addon[name] = addonElement.getAttribute(name);
+      }
+    }
+    addon.size = Number(addon.size) || undefined;
+
+    results.push(addon);
+  }
+
+  return {
+    usedFallback: false,
+    gmpAddons: results
+  };
+}
+
+/**
+ * If downloading from the network fails (AUS server is down),
+ * load the sources from local build configuration.
+ */
+function downloadLocalConfig() {
+
+  if (!GMPPrefs.get(GMPPrefs.KEY_UPDATE_ENABLED, true)) {
+    logger.info("Updates are disabled via media.gmp-manager.updateEnabled");
+    return Promise.resolve({usedFallback: true, gmpAddons: []});
+  }
+
+  return Promise.all(LOCAL_EME_SOURCES.map(conf => {
+    return downloadJSON(conf.src).then(addons => {
+
+      let platforms = addons.vendors[conf.id].platforms;
+      let target = Services.appinfo.OS + "_" + UpdateUtils.ABI;
+      let details = null;
+
+      while (!details) {
+        if (!(target in platforms)) {
+          // There was no matching platform so return false, this addon
+          // will be filtered from the results below
+          logger.info("no details found for: " + target);
+          return false;
+        }
+        // Field either has the details of the binary or is an alias
+        // to another build target key that does
+        if (platforms[target].alias) {
+          target = platforms[target].alias;
+        } else {
+          details = platforms[target];
+        }
+      }
+
+      logger.info("found plugin: " + conf.id);
+      return {
+        "id": conf.id,
+        "URL": details.fileUrl,
+        "hashFunction": addons.hashFunction,
+        "hashValue": details.hashValue,
+        "version": addons.vendors[conf.id].version,
+        "size": details.filesize
+      };
+    });
+  })).then(addons => {
+
+    // Some filters may not match this platform so
+    // filter those out
+    addons = addons.filter(x => x !== false);
+
+    return {
+      usedFallback: true,
+      gmpAddons: addons
+    };
+  });
+}
+
+/**
+ * Downloads file from a URL using XHR.
+ *
+ * @param  url
+ *         The url to download from.
+ * @return a promise that resolves to the path of a temporary file or rejects
+ *         with a JS exception in case of error.
+ */
+function downloadFile(url) {
+  return new Promise((resolve, reject) => {
+    let xhr = new XMLHttpRequest();
+    xhr.onload = function(response) {
+      logger.info("downloadXHR File download. status=" + xhr.status);
+      if (xhr.status != 200 && xhr.status != 206) {
+        reject(Components.Exception("File download failed", xhr.status));
+        return;
+      }
+      Task.spawn(function* () {
+        let f = yield OS.File.openUnique(OS.Path.join(OS.Constants.Path.tmpDir, "tmpaddon"));
+        let path = f.path;
+        logger.info(`Downloaded file will be saved to ${path}`);
+        yield f.file.close();
+        yield OS.File.writeAtomic(path, new Uint8Array(xhr.response));
+        return path;
+      }).then(resolve, reject);
+    };
+
+    let fail = (event) => {
+      let request = event.target;
+      let status = getRequestStatus(request);
+      let message = "Failed downloading via XHR, status: " + status +  ", reason: " + event.type;
+      logger.warn(message);
+      let ex = new Error(message);
+      ex.status = status;
+      reject(ex);
+    };
+    xhr.addEventListener("error", fail);
+    xhr.addEventListener("abort", fail);
+
+    xhr.responseType = "arraybuffer";
+    try {
+      xhr.open("GET", url);
+      // Use conservative TLS settings. See bug 1325501.
+      // TODO move to ServiceRequest.
+      if (xhr.channel instanceof Ci.nsIHttpChannelInternal) {
+        xhr.channel.QueryInterface(Ci.nsIHttpChannelInternal).beConservative = true;
+      }
+      xhr.send(null);
+    } catch (ex) {
+      reject(ex);
+    }
+  });
+}
+
+/**
+ * Convert a string containing binary values to hex.
+ */
+function binaryToHex(input) {
+  let result = "";
+  for (let i = 0; i < input.length; ++i) {
+    let hex = input.charCodeAt(i).toString(16);
+    if (hex.length == 1) {
+      hex = "0" + hex;
+    }
+    result += hex;
+  }
+  return result;
+}
+
+/**
+ * Calculates the hash of a file.
+ *
+ * @param  hashFunction
+ *         The type of hash function to use, must be supported by nsICryptoHash.
+ * @param  path
+ *         The path of the file to hash.
+ * @return a promise that resolves to hash of the file or rejects with a JS
+ *         exception in case of error.
+ */
+var computeHash = Task.async(function*(hashFunction, path) {
+  let file = yield OS.File.open(path, { existing: true, read: true });
+  try {
+    let hasher = Cc["@mozilla.org/security/hash;1"].
+                 createInstance(Ci.nsICryptoHash);
+    hasher.initWithString(hashFunction);
+
+    let bytes;
+    do {
+      bytes = yield file.read(HASH_CHUNK_SIZE);
+      hasher.update(bytes, bytes.length);
+    } while (bytes.length == HASH_CHUNK_SIZE);
+
+    return binaryToHex(hasher.finish(false));
+  }
+  finally {
+    yield file.close();
+  }
+});
+
+/**
+ * Verifies that a downloaded file matches what was expected.
+ *
+ * @param  properties
+ *         The properties to check, `size` and `hashFunction` with `hashValue`
+ *         are supported. Any properties missing won't be checked.
+ * @param  path
+ *         The path of the file to check.
+ * @return a promise that resolves if the file matched or rejects with a JS
+ *         exception in case of error.
+ */
+var verifyFile = Task.async(function*(properties, path) {
+  if (properties.size !== undefined) {
+    let stat = yield OS.File.stat(path);
+    if (stat.size != properties.size) {
+      throw new Error("Downloaded file was " + stat.size + " bytes but expected " + properties.size + " bytes.");
+    }
+  }
+
+  if (properties.hashFunction !== undefined) {
+    let expectedDigest = properties.hashValue.toLowerCase();
+    let digest = yield computeHash(properties.hashFunction, path);
+    if (digest != expectedDigest) {
+      throw new Error("Hash was `" + digest + "` but expected `" + expectedDigest +  "`.");
+    }
+  }
+});
+
+const ProductAddonChecker = {
+  /**
+   * Downloads a list of add-ons from a URL optionally testing the SSL
+   * certificate for certain attributes.
+   *
+   * @param  url
+   *         The url to download from.
+   * @param  allowNonBuiltIn
+   *         Whether to trust SSL certificates without a built-in CA issuer.
+   * @param  allowedCerts
+   *         The list of certificate attributes to match the SSL certificate
+   *         against or null to skip checks.
+   * @return a promise that resolves to an object containing the list of add-ons
+   *         and whether the local fallback was used, or rejects with a JS
+   *         exception in case of error.
+   */
+  getProductAddonList: function(url, allowNonBuiltIn = false, allowedCerts = null) {
+    if (!GMPPrefs.get(GMPPrefs.KEY_UPDATE_ENABLED, true)) {
+      logger.info("Updates are disabled via media.gmp-manager.updateEnabled");
+      return Promise.resolve({usedFallback: true, gmpAddons: []});
+    }
+
+    return downloadXML(url, allowNonBuiltIn, allowedCerts)
+      .then(parseXML)
+      .catch(downloadLocalConfig);
+  },
+
+  /**
+   * Downloads an add-on to a local file and checks that it matches the expected
+   * file. The caller is responsible for deleting the temporary file returned.
+   *
+   * @param  addon
+   *         The addon to download.
+   * @return a promise that resolves to the temporary file downloaded or rejects
+   *         with a JS exception in case of error.
+   */
+  downloadAddon: Task.async(function*(addon) {
+    let path = yield downloadFile(addon.URL);
+    try {
+      yield verifyFile(addon, path);
+      return path;
+    }
+    catch (e) {
+      yield OS.File.remove(path);
+      throw e;
+    }
+  })
+}