#!/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. output(){ echo -e '\e[36m'"$1"'\e[0m'; } unpriv(){ sudo -u nobody "$@" } # Compliance sudo systemctl mask debug-shell.service sudo systemctl mask kdump.service # Setup NTS unpriv curl https://raw.githubusercontent.com/GrapheneOS/infrastructure/main/chrony.conf | sudo tee /etc/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 # Make home directory private sudo chmod 700 /home/* # Setup Firewalld sudo firewall-cmd --permanent --remove-service=cockpit sudo firewall-cmd --reload sudo firewall-cmd --lockdown-on # Remove nullok sudo /usr/bin/sed -i 's/\s+nullok//g' /etc/pam.d/system-auth # Harden SSH unpriv curl https://raw.githubusercontent.com/TommyTran732/Linux-Setup-Scripts/main/etc/ssh/sshd_config.d/10-custom.conf | sudo tee /etc/ssh/sshd_config.d/10-custom.conf sudo chmod 644 /etc/ssh/sshd_config.d/10-custom.conf 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 unpriv curl https://raw.githubusercontent.com/GrapheneOS/infrastructure/main/systemd/system/sshd.service.d/local.conf | sudo tee /etc/systemd/system/sshd.service.d/override.conf sudo systemctl daemon-reload sudo systemctl restart sshd # Kernel hardening 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 sed -i 's/#install msr/install msr/g' /etc/modprobe.d/30_security-misc.conf sudo sed -i 's/# install bluetooth/install bluetooth/g' /etc/modprobe.d/30_security-misc.conf sudo sed -i 's/# install btusb/install btusb/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 sed -i 's/kernel.yama.ptrace_scope=2/kernel.yama.ptrace_scope=3/g' /etc/sysctl.d/990-security-misc.conf sudo sed -i 's/net.ipv4.icmp_echo_ignore_all=1/net.ipv4.icmp_echo_ignore_all=0/g' /etc/sysctl.d/990-security-misc.conf sudo sed -i 's/net.ipv6.icmp.echo_ignore_all=1/net.ipv6.icmp.echo_ignore_all=0/g' /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 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 dracut -f sudo sysctl -p sudo grubby --update-kernel=ALL --args='mitigations=auto,nosmt spectre_v2=on spec_store_bypass_disable=on tsx=off kvm.nx_huge_pages=force nosmt=force l1d_flush=on spec_rstack_overflow=safe-ret random.trust_bootloader=off random.trust_cpu=off intel_iommu=on amd_iommu=force_isolation efi=disable_early_pci_dma iommu=force iommu.passthrough=0 iommu.strict=1 slab_nomerge init_on_alloc=1 init_on_free=1 pti=on vsyscall=none ia32_emulation=0 page_alloc.shuffle=1 randomize_kstack_offset=on debugfs=off' # 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 daemon-reload sudo systemctl restart NetworkManager sudo mkdir -p /etc/systemd/system/irqbalance.service.d unpriv curl https://gitlab.com/divested/brace/-/raw/master/brace/usr/lib/systemd/system/irqbalance.service.d/99-brace.conf | sudo tee /etc/systemd/system/irqbalance.service.d/99-brace.conf sudo systemctl daemon-reload sudo systemctl restart irqbalance # Remove packages sudo dnf remove baobab chrome-gnome-shell evince firefox gedit gnome-calculator gnome-characters gnome-font-viewer gnome-screenshot gnome-tour qemu-guest-agent 'sssd*' 'yelp*' # Setup dnf unpriv curl https://raw.githubusercontent.com/TommyTran732/Linux-Setup-Scripts/main/etc/dnf/dnf.conf | sudo tee /etc/dnf/dnf.conf sudo sed -i 's/^metalink=.*/&\&protocol=https/g' /etc/yum.repos.d/* # Setup unbound sudo dnf install unbound -y echo 'server: chroot: "" auto-trust-anchor-file: "/var/lib/unbound/root.key" trust-anchor-signaling: yes root-key-sentinel: yes tls-ciphers: "PROFILE=SYSTEM" hide-http-user-agent: yes hide-identity: yes hide-trustanchor: yes hide-version: yes deny-any: yes harden-algo-downgrade: yes harden-large-queries: yes harden-referral-path: yes ignore-cd-flag: yes max-udp-size: 3072 module-config: "validator iterator" qname-minimisation-strict: yes unwanted-reply-threshold: 10000000 use-caps-for-id: yes outgoing-port-permit: 1024-65535 prefetch: yes prefetch-key: yes forward-zone: name: "." forward-tls-upstream: yes forward-addr: 1.1.1.2@853#security.cloudflare-dns.com forward-addr: 1.0.0.2@853#security.cloudflare-dns.com forward-addr: 2606:4700:4700::1112@853#security.cloudflare-dns.com forward-addr: 2606:4700:4700::1002@853#security.cloudflare-dns.com' | sudo tee /etc/unbound/unbound.conf mkdir -p /etc/systemd/system/unbound.service.d echo $'[Service] MemoryDenyWriteExecute=true PrivateDevices=true PrivateTmp=true ProtectHome=true ProtectClock=true ProtectControlGroups=true ProtectKernelLogs=true ProtectKernelModules=true # This breaks using socket options like \'so-rcvbuf\'. Explicitly disable for visibility. ProtectKernelTunables=true ProtectProc=invisible RestrictAddressFamilies=AF_INET AF_INET6 AF_NETLINK AF_UNIX RestrictRealtime=true SystemCallArchitectures=native SystemCallFilter=~@clock @cpu-emulation @debug @keyring @module mount @obsolete @resources RestrictNamespaces=yes LockPersonality=yes' | sudo tee /etc/systemd/system/unbound.service.d/override.conf sudo systemctl enable --now unbound # Setup yara sudo dnf install -y yara sudo insights-client --collector malware-detection sudo sed -i 's/test_scan: true/test_scan: false/' /etc/insights-client/malware-detection-config.yml # Setup automatic updates sudo sed -i 's/apply_updates = no/apply_updates = yes\nreboot = when-needed/g' /etc/dnf/automatic.conf sudo systemctl enable --now dnf-automatic.timer # Enable fstrim.timer sudo systemctl enable --now fstrim.timer ### Differentiating bare metal and virtual installs # Installing tuned first here because virt-what is 1 of its dependencies anyways sudo dnf install tuned -y virt_type=$(virt-what) if [ "$virt_type" = '' ]; then output 'Virtualization: Bare Metal.' elif [ "$virt_type" = 'openvz lxc' ]; then output 'Virtualization: OpenVZ 7.' elif [ "$virt_type" = 'xen xen-hvm' ]; then output 'Virtualization: Xen-HVM.' elif [ "$virt_type" = 'xen xen-hvm aws' ]; then output 'Virtualization: Xen-HVM on AWS.' else output "Virtualization: $virt_type." fi # Setup tuned if [ "$virt_type" = '' ]; then sudo tuned-adm profile latency-performance if [ "$virt_type" = 'kvm' ]; then sudo dnf install qemu-guest-agent -y fi else sudo tuned-adm profile virtual-guest fi # Setup real-ucode and hardened_malloc if [ "$virt_type" = '' ] || [ "${MACHINE_TYPE}" == 'x86_64' ]; then sudo dnf install 'https://divested.dev/rpm/fedora/divested-release-20231210-2.noarch.rpm' -y sudo sed -i 's/^metalink=.*/&?protocol=https/g' /etc/yum.repos.d/divested-release.repo if [ "${MACHINE_TYPE}" != 'x86_64' ]; then sudo dnf config-manager --save --setopt=divested.includepkgs=divested-release,real-ucode,microcode_ctl,amd-ucode-firmware sudo dnf install real-ucode -y sudo dracut -f elif [ "$virt_type" != '' ]; then sudo dnf config-manager --save --setopt=divested.includepkgs=divested-release,hardened_malloc sudo dnf install hardened_malloc -y else sudo dnf config-manager --save --setopt=divested.includepkgs=divested-release,real-ucode,microcode_ctl,amd-ucode-firmware,hardened_malloc sudo dnf install real-ucode hardened_malloc -y echo 'libhardened_malloc.so' | sudo tee /etc/ld.so.preload sudo dracut -f fi elif [ "${MACHINE_TYPE}" == 'aarch64' ]; then sudo dnf copr enable secureblue/hardened_malloc -y sudo dnf install hardened_malloc -y fi # Setup fwupd if [ "$virt_type" = '' ]; then sudo dnf install fwupd -y echo 'UriSchemes=file;https' | sudo tee -a /etc/fwupd/fwupd.conf sudo systemctl restart fwupd mkdir -p /etc/systemd/system/fwupd-refresh.service.d unpriv curl https://raw.githubusercontent.com/TommyTran732/Linux-Setup-Scripts/main/etc/systemd/system/fwupd-refresh.service.d/override.conf | sudo tee /etc/systemd/system/fwupd-refresh.service.d/override.conf sudo systemctl daemon-reload sudo systemctl enable --now fwupd-refresh.timer fi