Policies.jsm

/* 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 { XPCOMUtils } = ChromeUtils.import(
  "resource://gre/modules/XPCOMUtils.jsm"
);
const { Services } = ChromeUtils.import("resource://gre/modules/Services.jsm");
const { AppConstants } = ChromeUtils.import(
  "resource://gre/modules/AppConstants.jsm"
);

XPCOMUtils.defineLazyServiceGetters(this, {
  gCertDB: ["@mozilla.org/security/x509certdb;1", "nsIX509CertDB"],
  gXulStore: ["@mozilla.org/xul/xulstore;1", "nsIXULStore"],
});

XPCOMUtils.defineLazyModuleGetters(this, {
  AddonManager: "resource://gre/modules/AddonManager.jsm",
  BookmarksPolicies: "resource:///modules/policies/BookmarksPolicies.jsm",
  CustomizableUI: "resource:///modules/CustomizableUI.jsm",
  FileUtils: "resource://gre/modules/FileUtils.jsm",
  ProxyPolicies: "resource:///modules/policies/ProxyPolicies.jsm",
  WebsiteFilter: "resource:///modules/policies/WebsiteFilter.jsm",
});

XPCOMUtils.defineLazyGlobalGetters(this, ["File", "FileReader"]);

const PREF_LOGLEVEL = "browser.policies.loglevel";
const BROWSER_DOCUMENT_URL = AppConstants.BROWSER_CHROME_URL;

XPCOMUtils.defineLazyGetter(this, "log", () => {
  let { ConsoleAPI } = ChromeUtils.import("resource://gre/modules/Console.jsm");
  return new ConsoleAPI({
    prefix: "Policies.jsm",
    // tip: set maxLogLevel to "debug" and use log.debug() to create detailed
    // messages during development. See LOG_LEVELS in Console.jsm for details.
    maxLogLevel: "error",
    maxLogLevelPref: PREF_LOGLEVEL,
  });
});

var EXPORTED_SYMBOLS = ["Policies"];

/*
 * ============================
 * = POLICIES IMPLEMENTATIONS =
 * ============================
 *
 * The Policies object below is where the implementation for each policy
 * happens. An object for each policy should be defined, containing
 * callback functions that will be called by the engine.
 *
 * See the _callbacks object in EnterprisePolicies.js for the list of
 * possible callbacks and an explanation of each.
 *
 * Each callback will be called with two parameters:
 * - manager
 *   This is the EnterprisePoliciesManager singleton object from
 *   EnterprisePolicies.js
 *
 * - param
 *   The parameter defined for this policy in policies-schema.json.
 *   It will be different for each policy. It could be a boolean,
 *   a string, an array or a complex object. All parameters have
 *   been validated according to the schema, and no unknown
 *   properties will be present on them.
 *
 * The callbacks will be bound to their parent policy object.
 */
var Policies = {
  "3rdparty": {
    onBeforeAddons(manager, param) {
      manager.setExtensionPolicies(param.Extensions);
    },
  },

  AppUpdateURL: {
    onBeforeAddons(manager, param) {
      setDefaultPref("app.update.url", param.href);
    },
  },

  Authentication: {
    onBeforeAddons(manager, param) {
      let locked = true;
      if ("Locked" in param) {
        locked = param.Locked;
      }

      if ("SPNEGO" in param) {
        setDefaultPref(
          "network.negotiate-auth.trusted-uris",
          param.SPNEGO.join(", "),
          locked
        );
      }
      if ("Delegated" in param) {
        setDefaultPref(
          "network.negotiate-auth.delegation-uris",
          param.Delegated.join(", "),
          locked
        );
      }
      if ("NTLM" in param) {
        setDefaultPref(
          "network.automatic-ntlm-auth.trusted-uris",
          param.NTLM.join(", "),
          locked
        );
      }
      if ("AllowNonFQDN" in param) {
        if ("NTLM" in param.AllowNonFQDN) {
          setDefaultPref(
            "network.automatic-ntlm-auth.allow-non-fqdn",
            param.AllowNonFQDN.NTLM,
            locked
          );
        }
        if ("SPNEGO" in param.AllowNonFQDN) {
          setDefaultPref(
            "network.negotiate-auth.allow-non-fqdn",
            param.AllowNonFQDN.SPNEGO,
            locked
          );
        }
      }
      if ("AllowProxies" in param) {
        if ("NTLM" in param.AllowProxies) {
          setDefaultPref(
            "network.automatic-ntlm-auth.allow-proxies",
            param.AllowProxies.NTLM,
            locked
          );
        }
        if ("SPNEGO" in param.AllowProxies) {
          setDefaultPref(
            "network.negotiate-auth.allow-proxies",
            param.AllowProxies.SPNEGO,
            locked
          );
        }
      }
    },
  },

  BlockAboutAddons: {
    onBeforeUIStartup(manager, param) {
      if (param) {
        blockAboutPage(manager, "about:addons", true);
      }
    },
  },

  BlockAboutConfig: {
    onBeforeUIStartup(manager, param) {
      if (param) {
        blockAboutPage(manager, "about:config");
        setAndLockPref("devtools.chrome.enabled", false);
      }
    },
  },

  BlockAboutProfiles: {
    onBeforeUIStartup(manager, param) {
      if (param) {
        blockAboutPage(manager, "about:profiles");
      }
    },
  },

  BlockAboutSupport: {
    onBeforeUIStartup(manager, param) {
      if (param) {
        blockAboutPage(manager, "about:support");
      }
    },
  },

  Bookmarks: {
    onAllWindowsRestored(manager, param) {
      BookmarksPolicies.processBookmarks(param);
    },
  },

  CaptivePortal: {
    onBeforeAddons(manager, param) {
      setAndLockPref("network.captive-portal-service.enabled", param);
    },
  },

  Certificates: {
    onBeforeAddons(manager, param) {
      if ("ImportEnterpriseRoots" in param) {
        setAndLockPref(
          "security.enterprise_roots.enabled",
          param.ImportEnterpriseRoots
        );
      }
      if ("Install" in param) {
        (async () => {
          let dirs = [];
          let platform = AppConstants.platform;
          if (platform == "win") {
            dirs = [
              // Ugly, but there is no official way to get %USERNAME\AppData\Roaming\Mozilla.
              Services.dirsvc.get("XREUSysExt", Ci.nsIFile).parent,
              // Even more ugly, but there is no official way to get %USERNAME\AppData\Local\Mozilla.
              Services.dirsvc.get("DefProfLRt", Ci.nsIFile).parent.parent,
            ];
          } else if (platform == "macosx" || platform == "linux") {
            dirs = [
              // These two keys are named wrong. They return the Mozilla directory.
              Services.dirsvc.get("XREUserNativeManifests", Ci.nsIFile),
              Services.dirsvc.get("XRESysNativeManifests", Ci.nsIFile),
            ];
          }
          dirs.unshift(Services.dirsvc.get("XREAppDist", Ci.nsIFile));
          for (let certfilename of param.Install) {
            let certfile;
            try {
              certfile = Cc["@mozilla.org/file/local;1"].createInstance(
                Ci.nsIFile
              );
              certfile.initWithPath(certfilename);
            } catch (e) {
              for (let dir of dirs) {
                certfile = dir.clone();
                certfile.append(
                  platform == "linux" ? "certificates" : "Certificates"
                );
                certfile.append(certfilename);
                if (certfile.exists()) {
                  break;
                }
              }
            }
            let file;
            try {
              file = await File.createFromNsIFile(certfile);
            } catch (e) {
              log.error(`Unable to find certificate - ${certfilename}`);
              continue;
            }
            let reader = new FileReader();
            reader.onloadend = function() {
              if (reader.readyState != reader.DONE) {
                log.error(`Unable to read certificate - ${certfile.path}`);
                return;
              }
              let certFile = reader.result;
              let cert;
              try {
                cert = gCertDB.constructX509(certFile);
              } catch (e) {
                try {
                  // It might be PEM instead of DER.
                  cert = gCertDB.constructX509FromBase64(pemToBase64(certFile));
                } catch (ex) {
                  log.error(`Unable to add certificate - ${certfile.path}`);
                }
              }
              let now = Date.now() / 1000;
              if (cert) {
                gCertDB.asyncVerifyCertAtTime(
                  cert,
                  0x0008 /* certificateUsageSSLCA */,
                  0,
                  null,
                  now,
                  (aPRErrorCode, aVerifiedChain, aHasEVPolicy) => {
                    if (aPRErrorCode == Cr.NS_OK) {
                      // Certificate is already installed.
                      return;
                    }
                    try {
                      gCertDB.addCert(certFile, "CT,CT,");
                    } catch (e) {
                      // It might be PEM instead of DER.
                      gCertDB.addCertFromBase64(
                        pemToBase64(certFile),
                        "CT,CT,"
                      );
                    }
                  }
                );
              }
            };
            reader.readAsBinaryString(file);
          }
        })();
      }
    },
  },

  Cookies: {
    onBeforeUIStartup(manager, param) {
      addAllowDenyPermissions("cookie", param.Allow, param.Block);

      if (param.Block) {
        const hosts = param.Block.map(url => url.hostname)
          .sort()
          .join("\n");
        runOncePerModification("clearCookiesForBlockedHosts", hosts, () => {
          for (let blocked of param.Block) {
            Services.cookies.removeCookiesWithOriginAttributes(
              "{}",
              blocked.hostname
            );
          }
        });
      }

      if (
        param.Default !== undefined ||
        param.AcceptThirdParty !== undefined ||
        param.RejectTracker !== undefined ||
        param.Locked
      ) {
        const ACCEPT_COOKIES = 0;
        const REJECT_THIRD_PARTY_COOKIES = 1;
        const REJECT_ALL_COOKIES = 2;
        const REJECT_UNVISITED_THIRD_PARTY = 3;
        const REJECT_TRACKER = 4;

        let newCookieBehavior = ACCEPT_COOKIES;
        if (param.Default !== undefined && !param.Default) {
          newCookieBehavior = REJECT_ALL_COOKIES;
        } else if (param.AcceptThirdParty) {
          if (param.AcceptThirdParty == "never") {
            newCookieBehavior = REJECT_THIRD_PARTY_COOKIES;
          } else if (param.AcceptThirdParty == "from-visited") {
            newCookieBehavior = REJECT_UNVISITED_THIRD_PARTY;
          }
        } else if (param.RejectTracker !== undefined && param.RejectTracker) {
          newCookieBehavior = REJECT_TRACKER;
        }

        setDefaultPref(
          "network.cookie.cookieBehavior",
          newCookieBehavior,
          param.Locked
        );
      }

      const KEEP_COOKIES_UNTIL_EXPIRATION = 0;
      const KEEP_COOKIES_UNTIL_END_OF_SESSION = 2;

      if (param.ExpireAtSessionEnd !== undefined || param.Locked) {
        let newLifetimePolicy = KEEP_COOKIES_UNTIL_EXPIRATION;
        if (param.ExpireAtSessionEnd) {
          newLifetimePolicy = KEEP_COOKIES_UNTIL_END_OF_SESSION;
        }

        setDefaultPref(
          "network.cookie.lifetimePolicy",
          newLifetimePolicy,
          param.Locked
        );
      }
    },
  },

  DefaultDownloadDirectory: {
    onBeforeAddons(manager, param) {
      setDefaultPref("browser.download.dir", replacePathVariables(param));
      // If a custom download directory is being used, just lock folder list to 2.
      setAndLockPref("browser.download.folderList", 2);
    },
  },

  DisableAppUpdate: {
    onBeforeAddons(manager, param) {
      if (param) {
        manager.disallowFeature("appUpdate");
      }
    },
  },

  DisableBuiltinPDFViewer: {
    onBeforeAddons(manager, param) {
      if (param) {
        setAndLockPref("pdfjs.disabled", true);
      }
    },
  },

  DisableDeveloperTools: {
    onBeforeAddons(manager, param) {
      if (param) {
        setAndLockPref("devtools.policy.disabled", true);
        setAndLockPref("devtools.chrome.enabled", false);

        manager.disallowFeature("devtools");
        blockAboutPage(manager, "about:devtools");
        blockAboutPage(manager, "about:debugging");
        blockAboutPage(manager, "about:devtools-toolbox");
      }
    },
  },

  DisableFeedbackCommands: {
    onBeforeUIStartup(manager, param) {
      if (param) {
        manager.disallowFeature("feedbackCommands");
      }
    },
  },

  DisableFirefoxAccounts: {
    onBeforeAddons(manager, param) {
      if (param) {
        setAndLockPref("identity.fxaccounts.enabled", false);
        setAndLockPref("trailhead.firstrun.branches", "nofirstrun");
      }
    },
  },

  DisableFirefoxScreenshots: {
    onBeforeAddons(manager, param) {
      if (param) {
        setAndLockPref("extensions.screenshots.disabled", true);
      }
    },
  },

  DisableFirefoxStudies: {
    onBeforeAddons(manager, param) {
      if (param) {
        manager.disallowFeature("Shield");
        setAndLockPref(
          "browser.newtabpage.activity-stream.asrouter.userprefs.cfr.addons",
          false
        );
        setAndLockPref(
          "browser.newtabpage.activity-stream.asrouter.userprefs.cfr.features",
          false
        );
      }
    },
  },

  DisableForgetButton: {
    onProfileAfterChange(manager, param) {
      if (param) {
        setAndLockPref("privacy.panicButton.enabled", false);
      }
    },
  },

  DisableFormHistory: {
    onBeforeUIStartup(manager, param) {
      if (param) {
        setAndLockPref("browser.formfill.enable", false);
      }
    },
  },

  DisableMasterPasswordCreation: {
    onBeforeUIStartup(manager, param) {
      if (param) {
        manager.disallowFeature("createMasterPassword");
      }
    },
  },

  DisablePasswordReveal: {
    onBeforeUIStartup(manager, param) {
      if (param) {
        manager.disallowFeature("passwordReveal");
      }
    },
  },

  DisablePocket: {
    onBeforeAddons(manager, param) {
      if (param) {
        setAndLockPref("extensions.pocket.enabled", false);
      }
    },
  },

  DisablePrivateBrowsing: {
    onBeforeAddons(manager, param) {
      if (param) {
        manager.disallowFeature("privatebrowsing");
        blockAboutPage(manager, "about:privatebrowsing", true);
        setAndLockPref("browser.privatebrowsing.autostart", false);
      }
    },
  },

  DisableProfileImport: {
    onBeforeUIStartup(manager, param) {
      if (param) {
        manager.disallowFeature("profileImport");
        setAndLockPref(
          "browser.newtabpage.activity-stream.migrationExpired",
          true
        );
      }
    },
  },

  DisableProfileRefresh: {
    onBeforeUIStartup(manager, param) {
      if (param) {
        manager.disallowFeature("profileRefresh");
        setAndLockPref("browser.disableResetPrompt", true);
      }
    },
  },

  DisableSafeMode: {
    onBeforeUIStartup(manager, param) {
      if (param) {
        manager.disallowFeature("safeMode");
      }
    },
  },

  DisableSecurityBypass: {
    onBeforeUIStartup(manager, param) {
      if ("InvalidCertificate" in param) {
        setAndLockPref(
          "security.certerror.hideAddException",
          param.InvalidCertificate
        );
      }

      if ("SafeBrowsing" in param) {
        setAndLockPref(
          "browser.safebrowsing.allowOverride",
          !param.SafeBrowsing
        );
      }
    },
  },

  DisableSetDesktopBackground: {
    onBeforeUIStartup(manager, param) {
      if (param) {
        manager.disallowFeature("setDesktopBackground");
      }
    },
  },

  DisableSystemAddonUpdate: {
    onBeforeAddons(manager, param) {
      if (param) {
        manager.disallowFeature("SysAddonUpdate");
      }
    },
  },

  DisableTelemetry: {
    onBeforeAddons(manager, param) {
      if (param) {
        setAndLockPref("datareporting.healthreport.uploadEnabled", false);
        setAndLockPref("datareporting.policy.dataSubmissionEnabled", false);
        blockAboutPage(manager, "about:telemetry");
      }
    },
  },

  DisplayBookmarksToolbar: {
    onBeforeUIStartup(manager, param) {
      let value = (!param).toString();
      // This policy is meant to change the default behavior, not to force it.
      // If this policy was alreay applied and the user chose to re-hide the
      // bookmarks toolbar, do not show it again.
      runOncePerModification("displayBookmarksToolbar", value, () => {
        gXulStore.setValue(
          BROWSER_DOCUMENT_URL,
          "PersonalToolbar",
          "collapsed",
          value
        );
      });
    },
  },

  DisplayMenuBar: {
    onBeforeUIStartup(manager, param) {
      let value = (!param).toString();
      // This policy is meant to change the default behavior, not to force it.
      // If this policy was alreay applied and the user chose to re-hide the
      // menu bar, do not show it again.
      runOncePerModification("displayMenuBar", value, () => {
        gXulStore.setValue(
          BROWSER_DOCUMENT_URL,
          "toolbar-menubar",
          "autohide",
          value
        );
      });
    },
  },

  DNSOverHTTPS: {
    onBeforeAddons(manager, param) {
      if ("Enabled" in param) {
        let mode = param.Enabled ? 2 : 5;
        setDefaultPref("network.trr.mode", mode, param.Locked);
      }
      if (param.ProviderURL) {
        setDefaultPref("network.trr.uri", param.ProviderURL.href, param.Locked);
      }
    },
  },

  DontCheckDefaultBrowser: {
    onBeforeUIStartup(manager, param) {
      setAndLockPref("browser.shell.checkDefaultBrowser", !param);
    },
  },

  DownloadDirectory: {
    onBeforeAddons(manager, param) {
      setAndLockPref("browser.download.dir", replacePathVariables(param));
      // If a custom download directory is being used, just lock folder list to 2.
      setAndLockPref("browser.download.folderList", 2);
      // Per Chrome spec, user can't choose to download every time
      // if this is set.
      setAndLockPref("browser.download.useDownloadDir", true);
    },
  },

  EnableTrackingProtection: {
    onBeforeUIStartup(manager, param) {
      if (param.Value) {
        setDefaultPref(
          "privacy.trackingprotection.enabled",
          true,
          param.Locked
        );
        setDefaultPref(
          "privacy.trackingprotection.pbmode.enabled",
          true,
          param.Locked
        );
      } else {
        setAndLockPref("privacy.trackingprotection.enabled", false);
        setAndLockPref("privacy.trackingprotection.pbmode.enabled", false);
      }
      if ("Cryptomining" in param) {
        setDefaultPref(
          "privacy.trackingprotection.cryptomining.enabled",
          param.Cryptomining,
          param.Locked
        );
      }
      if ("Fingerprinting" in param) {
        setDefaultPref(
          "privacy.trackingprotection.fingerprinting.enabled",
          param.Fingerprinting,
          param.Locked
        );
      }
    },
  },

  Extensions: {
    onBeforeUIStartup(manager, param) {
      let uninstallingPromise = Promise.resolve();
      if ("Uninstall" in param) {
        uninstallingPromise = runOncePerModification(
          "extensionsUninstall",
          JSON.stringify(param.Uninstall),
          async () => {
            // If we're uninstalling add-ons, re-run the extensionsInstall runOnce even if it hasn't
            // changed, which will allow add-ons to be updated.
            Services.prefs.clearUserPref(
              "browser.policies.runOncePerModification.extensionsInstall"
            );
            let addons = await AddonManager.getAddonsByIDs(param.Uninstall);
            for (let addon of addons) {
              if (addon) {
                try {
                  await addon.uninstall();
                } catch (e) {
                  // This can fail for add-ons that can't be uninstalled.
                  log.debug(`Add-on ID (${addon.id}) couldn't be uninstalled.`);
                }
              }
            }
          }
        );
      }
      if ("Install" in param) {
        runOncePerModification(
          "extensionsInstall",
          JSON.stringify(param.Install),
          async () => {
            await uninstallingPromise;
            for (let location of param.Install) {
              let uri;
              try {
                // We need to try as a file first because
                // Windows paths are valid URIs.
                // This is done for legacy support (old API)
                let xpiFile = new FileUtils.File(location);
                uri = Services.io.newFileURI(xpiFile);
              } catch (e) {
                uri = Services.io.newURI(location);
              }
              installAddonFromURL(uri.spec);
            }
          }
        );
      }
      if ("Locked" in param) {
        for (let ID of param.Locked) {
          manager.disallowFeature(`uninstall-extension:${ID}`);
          manager.disallowFeature(`disable-extension:${ID}`);
        }
      }
    },
  },

  ExtensionSettings: {
    onBeforeAddons(manager, param) {
      try {
        manager.setExtensionSettings(param);
      } catch (e) {
        log.error("Invalid ExtensionSettings");
      }
    },
    async onBeforeUIStartup(manager, param) {
      let extensionSettings = param;
      let blockAllExtensions = false;
      if ("*" in extensionSettings) {
        if (
          "installation_mode" in extensionSettings["*"] &&
          extensionSettings["*"].installation_mode == "blocked"
        ) {
          blockAllExtensions = true;
          // Turn off discovery pane in about:addons
          setAndLockPref("extensions.getAddons.showPane", false);
          // Block about:debugging
          blockAboutPage(manager, "about:debugging");
        }
      }
      let { addons } = await AddonManager.getActiveAddons();
      let allowedExtensions = [];
      for (let extensionID in extensionSettings) {
        if (extensionID == "*") {
          // Ignore global settings
          continue;
        }
        if ("installation_mode" in extensionSettings[extensionID]) {
          if (
            extensionSettings[extensionID].installation_mode ==
              "force_installed" ||
            extensionSettings[extensionID].installation_mode ==
              "normal_installed"
          ) {
            if (!extensionSettings[extensionID].install_url) {
              throw new Error(`Missing install_url for ${extensionID}`);
            }
            if (!addons.find(addon => addon.id == extensionID)) {
              installAddonFromURL(
                extensionSettings[extensionID].install_url,
                extensionID
              );
            }
            manager.disallowFeature(`uninstall-extension:${extensionID}`);
            if (
              extensionSettings[extensionID].installation_mode ==
              "force_installed"
            ) {
              manager.disallowFeature(`disable-extension:${extensionID}`);
            }
            allowedExtensions.push(extensionID);
          } else if (
            extensionSettings[extensionID].installation_mode == "allowed"
          ) {
            allowedExtensions.push(extensionID);
          } else if (
            extensionSettings[extensionID].installation_mode == "blocked"
          ) {
            if (addons.find(addon => addon.id == extensionID)) {
              // Can't use the addon from getActiveAddons since it doesn't have uninstall.
              let addon = await AddonManager.getAddonByID(extensionID);
              try {
                await addon.uninstall();
              } catch (e) {
                // This can fail for add-ons that can't be uninstalled.
                log.debug(`Add-on ID (${addon.id}) couldn't be uninstalled.`);
              }
            }
          }
        }
      }
      if (blockAllExtensions) {
        for (let addon of addons) {
          if (
            addon.isSystem ||
            addon.isBuiltin ||
            !(addon.scope & AddonManager.SCOPE_PROFILE)
          ) {
            continue;
          }
          if (!allowedExtensions.includes(addon.id)) {
            try {
              // Can't use the addon from getActiveAddons since it doesn't have uninstall.
              let addonToUninstall = await AddonManager.getAddonByID(addon.id);
              await addonToUninstall.uninstall();
            } catch (e) {
              // This can fail for add-ons that can't be uninstalled.
              log.debug(`Add-on ID (${addon.id}) couldn't be uninstalled.`);
            }
          }
        }
      }
    },
  },

  ExtensionUpdate: {
    onBeforeAddons(manager, param) {
      if (!param) {
        setAndLockPref("extensions.update.enabled", param);
      }
    },
  },

  FirefoxHome: {
    onBeforeAddons(manager, param) {
      let locked = param.Locked || false;
      if ("Search" in param) {
        setDefaultPref(
          "browser.newtabpage.activity-stream.showSearch",
          param.Search,
          locked
        );
      }
      if ("TopSites" in param) {
        setDefaultPref(
          "browser.newtabpage.activity-stream.feeds.topsites",
          param.TopSites,
          locked
        );
      }
      if ("Highlights" in param) {
        setDefaultPref(
          "browser.newtabpage.activity-stream.feeds.section.highlights",
          param.Highlights,
          locked
        );
      }
      if ("Pocket" in param) {
        setDefaultPref(
          "browser.newtabpage.activity-stream.feeds.section.topstories",
          param.Pocket,
          locked
        );
      }
      if ("Snippets" in param) {
        setDefaultPref(
          "browser.newtabpage.activity-stream.feeds.snippets",
          param.Snippets,
          locked
        );
      }
    },
  },

  FlashPlugin: {
    onBeforeUIStartup(manager, param) {
      addAllowDenyPermissions("plugin:flash", param.Allow, param.Block);

      const FLASH_NEVER_ACTIVATE = 0;
      const FLASH_ASK_TO_ACTIVATE = 1;

      let flashPrefVal;
      if (param.Default === undefined || param.Default) {
        flashPrefVal = FLASH_ASK_TO_ACTIVATE;
      } else {
        flashPrefVal = FLASH_NEVER_ACTIVATE;
      }
      if (param.Locked) {
        setAndLockPref("plugin.state.flash", flashPrefVal);
      } else if (param.Default !== undefined) {
        setDefaultPref("plugin.state.flash", flashPrefVal);
      }
    },
  },

  HardwareAcceleration: {
    onBeforeAddons(manager, param) {
      if (!param) {
        setAndLockPref("layers.acceleration.disabled", true);
      }
    },
  },

  Homepage: {
    onBeforeUIStartup(manager, param) {
      // |homepages| will be a string containing a pipe-separated ('|') list of
      // URLs because that is what the "Home page" section of about:preferences
      // (and therefore what the pref |browser.startup.homepage|) accepts.
      if (param.URL) {
        let homepages = param.URL.href;
        if (param.Additional && param.Additional.length) {
          homepages += "|" + param.Additional.map(url => url.href).join("|");
        }
        setDefaultPref("browser.startup.homepage", homepages, param.Locked);
        if (param.Locked) {
          setAndLockPref(
            "pref.browser.homepage.disable_button.current_page",
            true
          );
          setAndLockPref(
            "pref.browser.homepage.disable_button.bookmark_page",
            true
          );
          setAndLockPref(
            "pref.browser.homepage.disable_button.restore_default",
            true
          );
        } else {
          // Clear out old run once modification that is no longer used.
          clearRunOnceModification("setHomepage");
        }
      }
      if (param.StartPage) {
        let prefValue;
        switch (param.StartPage) {
          case "none":
            prefValue = 0;
            break;
          case "homepage":
            prefValue = 1;
            break;
          case "previous-session":
            prefValue = 3;
            break;
        }
        setDefaultPref("browser.startup.page", prefValue, param.Locked);
      }
    },
  },

  InstallAddonsPermission: {
    onBeforeUIStartup(manager, param) {
      if ("Allow" in param) {
        addAllowDenyPermissions("install", param.Allow, null);
      }
      if ("Default" in param) {
        setAndLockPref("xpinstall.enabled", param.Default);
        if (!param.Default) {
          blockAboutPage(manager, "about:debugging");
          setAndLockPref(
            "browser.newtabpage.activity-stream.asrouter.userprefs.cfr.addons",
            false
          );
          setAndLockPref(
            "browser.newtabpage.activity-stream.asrouter.userprefs.cfr.features",
            false
          );
          manager.disallowFeature("xpinstall");
        }
      }
    },
  },

  LegacyProfiles: {
    // Handled in nsToolkitProfileService.cpp (Windows only)
  },

  LocalFileLinks: {
    onBeforeAddons(manager, param) {
      // If there are existing capabilities, lock them with the policy pref.
      let policyNames = Services.prefs
        .getCharPref("capability.policy.policynames", "")
        .split(" ");
      policyNames.push("localfilelinks_policy");
      setAndLockPref("capability.policy.policynames", policyNames.join(" "));
      setAndLockPref(
        "capability.policy.localfilelinks_policy.checkloaduri.enabled",
        "allAccess"
      );
      setAndLockPref(
        "capability.policy.localfilelinks_policy.sites",
        param.join(" ")
      );
    },
  },

  NetworkPrediction: {
    onBeforeAddons(manager, param) {
      setAndLockPref("network.dns.disablePrefetch", !param);
      setAndLockPref("network.dns.disablePrefetchFromHTTPS", !param);
    },
  },

  NewTabPage: {
    onBeforeAddons(manager, param) {
      setAndLockPref("browser.newtabpage.enabled", param);
    },
  },

  NoDefaultBookmarks: {
    onProfileAfterChange(manager, param) {
      if (param) {
        manager.disallowFeature("defaultBookmarks");
      }
    },
  },

  OfferToSaveLogins: {
    onBeforeUIStartup(manager, param) {
      setAndLockPref("signon.rememberSignons", param);
    },
  },