1 files changed, 180 insertions, 0 deletions
diff --git a/toolkit/modules/ServiceRequest.sys.mjs b/toolkit/modules/ServiceRequest.sys.mjs
new file mode 100644
index 0000000000..a88ba9c324
--- /dev/null
+++ b/toolkit/modules/ServiceRequest.sys.mjs
@@ -0,0 +1,180 @@
+/* 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/. */
+
+/**
+ * This module consolidates various code and data update requests, so flags
+ * can be set, Telemetry collected, etc. in a central place.
+ */
+
+import { XPCOMUtils } from "resource://gre/modules/XPCOMUtils.sys.mjs";
+
+const lazy = {};
+
+XPCOMUtils.defineLazyServiceGetter(
+  lazy,
+  "ProxyService",
+  "@mozilla.org/network/protocol-proxy-service;1",
+  "nsIProtocolProxyService"
+);
+
+ChromeUtils.defineESModuleGetters(lazy, {
+  ExtensionPreferencesManager:
+    "resource://gre/modules/ExtensionPreferencesManager.sys.mjs",
+});
+
+XPCOMUtils.defineLazyServiceGetter(
+  lazy,
+  "CaptivePortalService",
+  "@mozilla.org/network/captive-portal-service;1",
+  "nsICaptivePortalService"
+);
+
+XPCOMUtils.defineLazyServiceGetter(
+  lazy,
+  "gNetworkLinkService",
+  "@mozilla.org/network/network-link-service;1",
+  "nsINetworkLinkService"
+);
+
+const PROXY_CONFIG_TYPES = [
+  "direct",
+  "manual",
+  "pac",
+  "unused", // nsIProtocolProxyService.idl skips index 3.
+  "wpad",
+  "system",
+];
+
+function recordEvent(service, source = {}) {
+  try {
+    Services.telemetry.setEventRecordingEnabled("service_request", true);
+    Services.telemetry.recordEvent(
+      "service_request",
+      "bypass",
+      "proxy_info",
+      service,
+      source
+    );
+  } catch (err) {
+    // If the telemetry throws just log the error so it doesn't break any
+    // functionality.
+    console.error(err);
+  }
+}
+
+// If proxy.settings is used to change the proxy, an extension will
+// be "in control".  This returns the id of that extension.
+async function getControllingExtension() {
+  if (
+    !WebExtensionPolicy.getActiveExtensions().some(p =>
+      p.permissions.includes("proxy")
+    )
+  ) {
+    return undefined;
+  }
+  // Is this proxied by an extension that set proxy prefs?
+  let setting = await lazy.ExtensionPreferencesManager.getSetting(
+    "proxy.settings"
+  );
+  return setting?.id;
+}
+
+async function getProxySource(proxyInfo) {
+  // sourceId is set when using proxy.onRequest
+  if (proxyInfo.sourceId) {
+    return {
+      source: proxyInfo.sourceId,
+      type: "api",
+    };
+  }
+  let type = PROXY_CONFIG_TYPES[lazy.ProxyService.proxyConfigType] || "unknown";
+
+  // If we have a policy it will have set the prefs.
+  if (
+    Services.policies &&
+    Services.policies.status === Services.policies.ACTIVE
+  ) {
+    let policies = Services.policies.getActivePolicies()?.filter(p => p.Proxy);
+    if (policies?.length) {
+      return {
+        source: "policy",
+        type,
+      };
+    }
+  }
+
+  let source = await getControllingExtension();
+  return {
+    source: source || "prefs",
+    type,
+  };
+}
+
+/**
+ * ServiceRequest is intended to be a drop-in replacement for current users
+ * of XMLHttpRequest.
+ *
+ * @param {Object} options - Options for underlying XHR, e.g. { mozAnon: bool }
+ */
+export class ServiceRequest extends XMLHttpRequest {
+  constructor(options) {
+    super(options);
+  }
+  /**
+   * Opens an XMLHttpRequest, and sets the NSS "beConservative" flag.
+   * Requests are always async.
+   *
+   * @param {String} method - HTTP method to use, e.g. "GET".
+   * @param {String} url - URL to open.
+   * @param {Object} options - Additional options { bypassProxy: bool }.
+   */
+  open(method, url, options) {
+    super.open(method, url, true);
+
+    if (super.channel instanceof Ci.nsIHttpChannelInternal) {
+      let internal = super.channel.QueryInterface(Ci.nsIHttpChannelInternal);
+      // Disable cutting edge features, like TLS 1.3, where middleboxes might brick us
+      internal.beConservative = true;
+      // Disable use of proxy for this request if necessary.
+      if (options?.bypassProxy && this.bypassProxyEnabled) {
+        internal.bypassProxy = true;
+      }
+    }
+  }
+
+  get bypassProxy() {
+    let { channel } = this;
+    return channel.QueryInterface(Ci.nsIHttpChannelInternal).bypassProxy;
+  }
+
+  get isProxied() {
+    let { channel } = this;
+    return !!(channel instanceof Ci.nsIProxiedChannel && channel.proxyInfo);
+  }
+
+  get bypassProxyEnabled() {
+    return Services.prefs.getBoolPref("network.proxy.allow_bypass", true);
+  }
+
+  static async logProxySource(channel, service) {
+    if (channel.proxyInfo) {
+      let source = await getProxySource(channel.proxyInfo);
+      recordEvent(service, source);
+    }
+  }
+
+  static get isOffline() {
+    try {
+      return (
+        Services.io.offline ||
+        lazy.CaptivePortalService.state ==
+          lazy.CaptivePortalService.LOCKED_PORTAL ||
+        !lazy.gNetworkLinkService.isLinkUp
+      );
+    } catch (ex) {
+      // we cannot get state, assume the best.
+    }
+    return false;
+  }
+}