The Tor Browser / file revision

 #!/bin/bash

 # Copyright (c) 2012 The Chromium Authors. All rights reserved.

 # Use of this source code is governed by a BSD-style license that can be

 # found in the LICENSE file.

 # Usage: make_more_helpers.sh <directory_within_contents> <app_name>

 #

 # This script creates additional helper .app bundles for Chromium, based on

 # the existing helper .app bundle, changing their Mach-O header's flags to

 # enable and disable various features. Based on Chromium Helper.app, it will

 # create Chromium Helper EH.app, which has the MH_NO_HEAP_EXECUTION bit

 # cleared to support Chromium child processes that require an executable heap,

 # and Chromium Helper NP.app, which has the MH_PIE bit cleared to support

 # Chromium child processes that cannot tolerate ASLR.

 #

 # This script expects to be called from the chrome_exe target as a postbuild,

 # and operates directly within the built-up browser app's versioned directory.

 #

 # Each helper is adjusted by giving it the proper bundle name, renaming the

 # executable, adjusting several Info.plist keys, and changing the executable's

 # Mach-O flags.

 set -eu

 make_helper() {

   local containing_dir="${1}"

   local app_name="${2}"

   local feature="${3}"

   local flags="${4}"

   local helper_name="${app_name} Helper"

   local helper_stem="${containing_dir}/${helper_name}"

   local original_helper="${helper_stem}.app"

   if [[ ! -d "${original_helper}" ]]; then

     echo "${0}: error: ${original_helper} is a required directory" >& 2

     exit 1

   fi

   local original_helper_exe="${original_helper}/Contents/MacOS/${helper_name}"

   if [[ ! -f "${original_helper_exe}" ]]; then

     echo "${0}: error: ${original_helper_exe} is a required file" >& 2

     exit 1

   fi

   local feature_helper="${helper_stem} ${feature}.app"

   rsync -acC --delete --include '*.so' "${original_helper}/" "${feature_helper}"

   local helper_feature="${helper_name} ${feature}"

   local helper_feature_exe="${feature_helper}/Contents/MacOS/${helper_feature}"

   mv "${feature_helper}/Contents/MacOS/${helper_name}" "${helper_feature_exe}"

   local change_flags="$(dirname "${0}")/change_mach_o_flags.py"

   "${change_flags}" ${flags} "${helper_feature_exe}"

   local feature_info="${feature_helper}/Contents/Info"

   local feature_info_plist="${feature_info}.plist"

   defaults write "${feature_info}" "CFBundleDisplayName" "${helper_feature}"

   defaults write "${feature_info}" "CFBundleExecutable" "${helper_feature}"

   cfbundleid="$(defaults read "${feature_info}" "CFBundleIdentifier")"

   feature_cfbundleid="${cfbundleid}.${feature}"

   defaults write "${feature_info}" "CFBundleIdentifier" "${feature_cfbundleid}"

   cfbundlename="$(defaults read "${feature_info}" "CFBundleName")"

   feature_cfbundlename="${cfbundlename} ${feature}"

   defaults write "${feature_info}" "CFBundleName" "${feature_cfbundlename}"

   # As usual, defaults might have put the plist into whatever format excites

   # it, but Info.plists get converted back to the expected XML format.

   plutil -convert xml1 "${feature_info_plist}"

   # `defaults` also changes the file permissions, so make the file

   # world-readable again.

   chmod a+r "${feature_info_plist}"

 }

 if [[ ${#} -ne 2 ]]; then

   echo "usage: ${0} <directory_within_contents> <app_name>" >& 2

   exit 1

 fi

 DIRECTORY_WITHIN_CONTENTS="${1}"

 APP_NAME="${2}"

 CONTENTS_DIR="${BUILT_PRODUCTS_DIR}/${CONTENTS_FOLDER_PATH}"

 CONTAINING_DIR="${CONTENTS_DIR}/${DIRECTORY_WITHIN_CONTENTS}"

 make_helper "${CONTAINING_DIR}" "${APP_NAME}" "EH" "--executable-heap"

 make_helper "${CONTAINING_DIR}" "${APP_NAME}" "NP" "--no-pie"