gecko-dev/toolkit/modules/PermissionsUtils.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/.

var EXPORTED_SYMBOLS = ["PermissionsUtils"];

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

var gImportedPrefBranches = new Set();

function importPrefBranch(aPrefBranch, aPermission, aAction) {
  let list = Services.prefs.getChildList(aPrefBranch);

  for (let pref of list) {
    let origins = Services.prefs.getCharPref(pref, "");

    if (!origins) {
      continue;
    }

    origins = origins.split(",");

    for (let origin of origins) {
      let principals = [];
      try {
        principals = [
          Services.scriptSecurityManager.createContentPrincipalFromOrigin(
            origin
          ),
        ];
      } catch (e) {
        // This preference used to contain a list of hosts. For back-compat
        // reasons, we convert these hosts into http:// and https:// permissions
        // on default ports.
        try {
          let httpURI = Services.io.newURI("http://" + origin);
          let httpsURI = Services.io.newURI("https://" + origin);

          principals = [
            Services.scriptSecurityManager.createContentPrincipal(httpURI, {}),
            Services.scriptSecurityManager.createContentPrincipal(httpsURI, {}),
          ];
        } catch (e2) {}
      }

      for (let principal of principals) {
        try {
          Services.perms.addFromPrincipal(principal, aPermission, aAction);
        } catch (e) {}
      }
    }

    Services.prefs.setCharPref(pref, "");
  }
}

var PermissionsUtils = {
  /**
   * Import permissions from perferences to the Permissions Manager. After being
   * imported, all processed permissions will be set to an empty string.
   * Perferences are only processed once during the application's
   * lifetime - it's safe to call this multiple times without worrying about
   * doing unnecessary work, as the preferences branch will only be processed
   * the first time.
   *
   * @param aPrefBranch  Preferences branch to import from. The preferences
   *                     under this branch can specify whitelist (ALLOW_ACTION)
   *                     or blacklist (DENY_ACTION) additions using perference
   *                     names of the form:
   *                     * <BRANCH>.whitelist.add.<ID>
   *                     * <BRANCH>.blacklist.add.<ID>
   *                     Where <ID> can be any valid preference name.
   *                     The value is expected to be a comma separated list of
   *                     host named. eg:
   *                     * something.example.com
   *                     * foo.exmaple.com,bar.example.com
   *
   * @param aPermission Permission name to be passsed to the Permissions
   *                    Manager.
   */
  importFromPrefs(aPrefBranch, aPermission) {
    if (!aPrefBranch.endsWith(".")) {
      aPrefBranch += ".";
    }

    // Ensure we only import this pref branch once.
    if (gImportedPrefBranches.has(aPrefBranch)) {
      return;
    }

    importPrefBranch(
      aPrefBranch + "whitelist.add",
      aPermission,
      Services.perms.ALLOW_ACTION
    );
    importPrefBranch(
      aPrefBranch + "blacklist.add",
      aPermission,
      Services.perms.DENY_ACTION
    );

    gImportedPrefBranches.add(aPrefBranch);
  },
};