#!/bin/bash

#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
#Customize it to your liking
#Run this script as your admin user, NOT root

#Setting umask to 077
umask 077
sudo sed -ie '/^DIR_MODE=/ s/=[0-9]*\+/=0700/' /etc/adduser.conf
sudo sed -ie '/^UMASK\s\+/ s/022/077/' /etc/login.defs
sudo sed -i 's/USERGROUPS_ENAB yes/USERGROUPS_ENAB no/g' /etc/login.defs
echo "umask 077" | sudo tee --append /etc/profile

#Make sure the system has curl (minimal installs do not include it)
sudo apt install -y curl

#Security kernel settings
sudo curl https://raw.githubusercontent.com/Kicksecure/security-misc/master/etc/modprobe.d/30_security-misc.conf -o /etc/modprobe.d/30_security-misc.conf
sudo curl https://raw.githubusercontent.com/Kicksecure/security-misc/master/etc/sysctl.d/30_security-misc.conf -o /etc/sysctl.d/30_security-misc.conf
sudo curl https://raw.githubusercontent.com/Kicksecure/security-misc/master/etc/sysctl.d/30_silent-kernel-printk.conf -o /etc/sysctl.d/30_silent-kernel-printk.conf
sudo curl https://raw.githubusercontent.com/Kicksecure/security-misc/master/etc/sysctl.d/30_security-misc_kexec-disable.conf -o /etc/sysctl.d/30_security-misc_kexec-disable.conf

#Systemd Hardening
sudo mkdir -p /etc/systemd/system/NetworkManager.service.d
sudo curl https://gitlab.com/divested/brace/-/raw/master/brace/usr/lib/systemd/system/NetworkManager.service.d/99-brace.conf -o /etc/systemd/system/NetworkManager.service.d/99-brace.conf
sudo mkdir -p /etc/systemd/system/irqbalance.service.d
sudo curl https://gitlab.com/divested/brace/-/raw/master/brace/usr/lib/systemd/system/irqbalance.service.d/99-brace.conf -o /etc/systemd/system/irqbalance.service.d/99-brace.conf
sudo mkdir -p /etc/systemd/system/sshd.service.d
sudo curl https://raw.githubusercontent.com/GrapheneOS/infrastructure/main/systemd/system/sshd.service.d/limits.conf -o /etc/systemd/system/sshd.service.d/limits.conf

echo "GSSAPIAuthentication no" | sudo tee /etc/ssh/ssh_config.d/10-custom.conf
echo "VerifyHostKeyDNS yes" | sudo tee -a /etc/ssh/ssh_config.d/10-custom.conf

#Setup NTS
rm -rf /etc/chrony/chrony.conf
curl https://raw.githubusercontent.com/GrapheneOS/infrastructure/main/chrony.conf -o /etc/chrony/chrony.conf

#Disable crash reports
gsettings set com.ubuntu.update-notifier show-apport-crashes false
ubuntu-report -f send no
sudo systemctl stop apport.service
sudo systemctl disable apport.service
sudo systemctl mask apport.service
sudo systemctl stop whoopsie.service
sudo systemctl disable whoopsie.service
sudo systemctl mask whoopsie.service

#Update packages and firmware
sudo apt update -y
sudo apt full-upgrade -y
sudo fwupdmgr get-devices
sudo fwupdmgr refresh --force
sudo fwupdmgr get-updates -y
sudo fwupdmgr update -y

#Remove unneeded packages
apt purge -y gnome-calculator

#Install packages that I use
apt install -y gnome-console

#Randomize MAC address
sudo bash -c 'cat > /etc/NetworkManager/conf.d/00-macrandomize.conf' <<-'EOF'
[device]
wifi.scan-rand-mac-address=yes
[connection]
wifi.cloned-mac-address=random
ethernet.cloned-mac-address=random
connection.stable-id=${CONNECTION}/${BOOT}
EOF

sudo systemctl restart NetworkManager