#!/bin/bash
# Copyright 2021 Google LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#    https://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

## Section: 5.3.3 Ensure password reuse is limited (Not Scored) ##
# Check if the changes have already been made
if ! grep -q \
  "password[[:space:]]*required[[:space:]]*pam_pwhistory.so[[:space:]]*remember=5" \
  /etc/pam.d/system-auth; then
  sed -i \
    '0,/password/s//password        required        pam_pwhistory.so remember=5\n&/' \
    /etc/pam.d/system-auth
fi
if ! grep -q \
  "password[[:space:]]*required[[:space:]]*pam_unix.so[[:space:]]*remember=5" \
  /etc/pam.d/system-auth; then
  sed -i 's/password.*pam_unix.so/& remember=5/' /etc/pam.d/system-auth
fi