#!/bin/bash

# Copyright (C) 2021-2024 Thien Tran
#
# 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
#
# http://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.

#Please note that this is how I PERSONALLY setup my computer - I do some stuff such as not using anything to download GNOME extensions from extensions.gnome.org and installing the extensions as a package instead

# Meant to run as the normal user - other stuff needs to be done with transactional-update shell

output(){
    echo -e '\e[36m'"$1"'\e[0m';
}

unpriv(){
    sudo -u nobody "$@"
}

# Compliance
sudo systemctl mask debug-shell.service
sudo systemctl mask kdump.service

# Make home directory private
sudo chmod 700 /home/*

# Setup NTS
sudo rm -rf /etc/chrony/chrony.conf
unpriv curl https://raw.githubusercontent.com/GrapheneOS/infrastructure/main/chrony.conf | sudo tee /etc/chrony/chrony.conf
unpriv curl https://raw.githubusercontent.com/TommyTran732/Linux-Setup-Scripts/main/etc/sysconfig/chronyd | sudo tee /etc/sysconfig/chronyd

sudo systemctl restart chronyd

# Setup Networking
unpriv curl https://raw.githubusercontent.com/TommyTran732/Linux-Setup-Scripts/main/etc/NetworkManager/conf.d/00-macrandomize.conf | sudo tee /etc/NetworkManager/conf.d/00-macrandomize.conf
unpriv curl https://raw.githubusercontent.com/TommyTran732/Linux-Setup-Scripts/main/etc/NetworkManager/conf.d/01-transient-hostname.conf | sudo tee /etc/NetworkManager/conf.d/01-transient-hostname.conf
sudo nmcli general reload conf
sudo hostnamectl hostname 'localhost'
sudo hostnamectl --transient hostname ''
sudo firewall-cmd --set-default-zone=block
sudo firewall-cmd --permanent --add-service=dhcpv6-client
sudo firewall-cmd --reload
sudo firewall-cmd --lockdown-on

# Harden SSH
unpriv curl https://raw.githubusercontent.com/TommyTran732/Linux-Setup-Scripts/main/etc/ssh/ssh_config.d/10-custom.conf | sudo tee /etc/ssh/ssh_config.d/10-custom.conf
sudo chmod 644 /etc/ssh/ssh_config.d/10-custom.conf

# Security kernel settings
unpriv curl https://raw.githubusercontent.com/Kicksecure/security-misc/master/etc/modprobe.d/30_security-misc.conf | sudo tee /etc/modprobe.d/30_security-misc.conf
sudo chmod 644 /etc/modprobe.d/30_security-misc.conf
sudo sed -i 's/#install msr/install msr/g' /etc/modprobe.d/30_security-misc.conf
unpriv curl https://raw.githubusercontent.com/Kicksecure/security-misc/master/usr/lib/sysctl.d/990-security-misc.conf | sudo tee /etc/sysctl.d/990-security-misc.conf
sudo chmod 644 /etc/sysctl.d/990-security-misc.conf
unpriv curl https://raw.githubusercontent.com/Kicksecure/security-misc/master/usr/lib/sysctl.d/30_silent-kernel-printk.conf | sudo tee /etc/sysctl.d/30_silent-kernel-printk.conf
sudo chmod 644 /etc/sysctl.d/30_silent-kernel-printk.conf
unpriv curl https://raw.githubusercontent.com/Kicksecure/security-misc/master/usr/lib/sysctl.d/30_security-misc_kexec-disable.conf | sudo tee /etc/sysctl.d/30_security-misc_kexec-disable.conf
sudo chmod 644 /etc/sysctl.d/30_security-misc_kexec-disable.conf
sudo sed -i 's/kernel.yama.ptrace_scope=2/kernel.yama.ptrace_scope=3/g' /etc/sysctl.d/990-security-misc.conf

# Disable coredump
unpriv curl https://raw.githubusercontent.com/TommyTran732/Linux-Setup-Scripts/main/etc/security/limits.d/30-disable-coredump.conf | sudo tee /etc/security/limits.d/30-disable-coredump.conf

# Systemd Hardening
sudo mkdir -p /etc/systemd/system/NetworkManager.service.d
unpriv curl https://gitlab.com/divested/brace/-/raw/master/brace/usr/lib/systemd/system/NetworkManager.service.d/99-brace.conf | sudo tee /etc/systemd/system/NetworkManager.service.d/99-brace.conf
sudo systemctl restart NetworkManager

# Setup dconf (does not seem to work - need to double check why)
umask 022

unpriv curl https://raw.githubusercontent.com/TommyTran732/Linux-Setup-Scripts/main/etc/dconf/db/local.d/automount-disable | sudo tee /etc/dconf/db/local.d/automount-disable
unpriv curl https://raw.githubusercontent.com/TommyTran732/Linux-Setup-Scripts/main/etc/dconf/db/local.d/locks/automount-disable | sudo tee /etc/dconf/db/local.d/locks/automount-disable

unpriv curl https://raw.githubusercontent.com/TommyTran732/Linux-Setup-Scripts/main/etc/dconf/db/local.d/prefer-dark | sudo tee /etc/dconf/db/local.d/prefer-dark
unpriv curl https://raw.githubusercontent.com/TommyTran732/Linux-Setup-Scripts/main/etc/dconf/db/local.d/adw-gtk3-dark | sudo tee /etc/dconf/db/local.d/adw-gtk3-dark
unpriv curl https://raw.githubusercontent.com/TommyTran732/Linux-Setup-Scripts/main/etc/dconf/db/local.d/button-layout | sudo tee /etc/dconf/db/local.d/button-layout
unpriv curl https://raw.githubusercontent.com/TommyTran732/Linux-Setup-Scripts/main/etc/dconf/db/local.d/touchpad | sudo tee /etc/dconf/db/local.d/touchpad

sudo dconf update
umask 077

# Setup Flatpak
sudo flatpak override --system --nosocket=x11 --nosocket=fallback-x11 --nosocket=pulseaudio --unshare=network --unshare=ipc --nofilesystem=host:reset --nodevice=input --nodevice=shm --nodevice=all --no-talk-name=org.freedesktop.Flatpak --no-talk-name=org.freedesktop.systemd1 --no-talk-name=org.gnome.Shell.Extensions
flatpak override --user --nosocket=x11 --nosocket=fallback-x11 --nosocket=pulseaudio --unshare=network --unshare=ipc --nofilesystem=host:reset --nodevice=input --nodevice=shm --nodevice=all --no-talk-name=org.freedesktop.Flatpak --no-talk-name=org.freedesktop.systemd1 --no-talk-name=org.gnome.Shell.Extensions
flatpak remote-add --if-not-exists --user flathub https://dl.flathub.org/repo/flathub.flatpakrepo
flatpak --user install org.gnome.Extensions com.github.tchx84.Flatseal org.gnome.Loupe -y
flatpak --user override com.github.tchx84.Flatseal --filesystem=/var/lib/flatpak/app:ro --filesystem=xdg-data/flatpak/app:ro --filesystem=xdg-data/flatpak/overrides:create
flatpak update -y