#cloud-config
# Make sure to check the cloud-init logs: /var/log/cloud-init.log and /var/log/cloud-init-output.log
# Author: Marcus Kammer
# Tested: Ubuntu 22.04
# Copyright © 2023 Marcus Kammer

# Permission is hereby granted, free of charge, to any person obtaining a copy of
# this software and associated documentation files (the “Software”), to deal in
# the Software without restriction, including without limitation the rights to
# use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
# of the Software, and to permit persons to whom the Software is furnished to do
# so, subject to the following conditions:

# The above copyright notice and this permission notice shall be included in all
# copies or substantial portions of the Software.

# THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.
locale: en_US.UTF-8
keyboard:
  layout: us
timezone: Europe/Berlin

groups:
  - nginxgroup

users:
  - name: nginxuser
    system: true
    shell: /usr/sbin/nologin
    groups: nginxgroup
    sudo: null
  # Create a new user named 'cl'
  - name: cl
    # Add the user to the 'users' and 'admin' groups
    groups: users, admin
    # Allow the user to execute any command with sudo without entering a password
    sudo: ALL=(ALL) NOPASSWD:ALL
    # Set the user's default shell to /bin/bash
    shell: /bin/bash
    # Add the user's public SSH key for key-based authentication
    ssh_authorized_keys:
      - ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIA+46Y3AHPLJgz8KK61doqH3jBX2TL3TJvZsJrB9Km03 visua@xps-8930
      - ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIMIHJ5qpMIKL7N3nC0GG1O4ygtkqOlQuZReoik6xGBxn marcus@XPS-13-9380.local
      - ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIB6xSH5nE0uy0C0kglpp4EqrbbW2CrBeAIj+X6Sf2pd0 XPS-8930-Ubuntu_22

packages:
  - detachtty
  - fail2ban
  - ufw
  - unattended-upgrades
  - sbcl
  - mosh
  - tmux
  - git
  - nginx
  - certbot
  - python3-certbot-nginx
  - build-essential
  - libzstd-dev
  - libsqlite3-dev
  - sqlite3
  - curl
  - wget

package_update: true
package_upgrade: true

write_files:
  - path: /etc/apt/apt.conf.d/20auto-upgrades
    content: |
      APT::Periodic::Update-Package-Lists "1";
      APT::Periodic::Download-Upgradeable-Packages "1";
      APT::Periodic::AutocleanInterval "7";
      APT::Periodic::Unattended-Upgrade "1";

  - path: /etc/ssh/sshd_config
    content: |
      # Include additional configuration files from the specified directory
      Include /etc/ssh/sshd_config.d/*.conf
      # Set the maximum number of authentication attempts allowed per connection
      MaxAuthTries 3
      # Specifies the file containing public keys for user authentication
      AuthorizedKeysFile .ssh/authorized_keys
      # Disables password authentication
      PasswordAuthentication no
      # Specifies the authentication method(s) to use (public key authentication in this case)
      AuthenticationMethods publickey
      # Enables public key authentication
      PubkeyAuthentication yes
      # Disables root login via SSH
      PermitRootLogin no
      # Disables keyboard-interactive authentication
      KbdInteractiveAuthentication no
      # Enables the Pluggable Authentication Module (PAM) for authentication
      UsePAM yes
      # Disables agent forwarding for SSH connections
      AllowAgentForwarding no
      # Enables TCP forwarding for SSH connections
      AllowTcpForwarding yes
      # Disables X11 forwarding for SSH connections
      X11Forwarding no
      # Disables printing of the message of the day (MOTD) when a user logs in
      PrintMotd no
      # Specifies the key exchange algorithms to use
      KexAlgorithms curve25519-sha256@libssh.org
      # Specifies the ciphers allowed for protocol version 2
      Ciphers chacha20-poly1305@openssh.com
      # Specifies the message authentication code (MAC) algorithms in order of preference
      MACs hmac-sha2-512-etm@openssh.com
      # Specifies environment variables sent by the client to the server
      AcceptEnv LANG LC_*
      # Specifies the command to use for the SFTP subsystem
      Subsystem sftp /usr/lib/openssh/sftp-server
      # Specifies the user(s) allowed to log in via SSH (in this case, only the user "marcus")
      AllowUsers cl

  - path: /etc/fail2ban/jail.local
    content: |
      [DEFAULT]
      # Ban time (in seconds) for an IP after reaching the max number of retries.
      bantime = 3600
      # Time window (in seconds) in which 'maxretry' failures must occur.
      findtime = 600
      # Maximum number of failed login attempts before an IP gets banned.
      maxretry = 3
      # Ban action to use (ufw in this case).
      banaction = ufw

      [sshd]
      # Enable the sshd jail.
      enabled = true
      # Specify the port for the sshd service.
      port = 22
      # Path to the log file for the sshd service.
      logpath = /var/log/auth.log

      [sshd-ddos]
      # Specify the filter to use (created earlier)
      filter = sshd
      # Enable the sshd-ddos jail.
      enabled = true
      # Specify the port for the sshd service.
      port = ssh
      # Path to the log file for the sshd service.
      logpath = /var/log/auth.log
      # Maximum number of failed login attempts before an IP gets banned (for DDoS protection).
      maxretry = 5
      # Ban time (in seconds) for an IP after reaching the max number of retries (for DDoS protection).
      bantime = 600

      [nginx-http-auth]
      # Enable the jail
      enabled = true
      # Specify the filter to use (created earlier)
      # filter = nginx-http-auth
      # Define the action to take (using UFW)
      action = ufw
      # Specify the log file to monitor
      logpath = /var/log/nginx/error.log
      # Set the maximum number of failed attempts before banning
      maxretry = 6
      # Set the ban time in seconds (1 hour)
      bantime = 3600
      # Set the time window for failed attempts in seconds (10 minutes)
      findtime = 600

  - path: /etc/nginx/nginx.conf
    content: |
      user nginxuser;
      worker_processes auto;
      pid /run/nginx.pid;
      include /etc/nginx/modules-enabled/*.conf;
      events {
        worker_connections 768;
        # multi_accept on;
      }
      http {
        ##
        # Basic Settings
        ##
        sendfile on;
        tcp_nopush on;
        types_hash_max_size 2048;
        # server_tokens off;
        # server_names_hash_bucket_size 64;
        # server_name_in_redirect off;
        include /etc/nginx/mime.types;
        default_type application/octet-stream;
        ##
        # SSL Settings
        ##
        ssl_protocols TLSv1.2 TLSv1.3; # Dropping SSLv3, ref: POODLE
        ssl_prefer_server_ciphers on;
        ##
        # Logging Settings
        ##
        log_format csv '$time_iso8601,$remote_addr,$remote_user,"$request",$status,$body_bytes_sent,$http_referer,"$http_user_agent"';
        access_log /var/log/nginx/access.csv csv;
        error_log /var/log/nginx/error.log;
        ##
        # Gzip Settings
        ##
        gzip on;
        # gzip_vary on;
        # gzip_proxied any;
        # gzip_comp_level 6;
        # gzip_buffers 16 8k;
        # gzip_http_version 1.1;
        # gzip_types text/plain text/css application/json application/javascript text/xml application/xml application/xml+rss text/javascript;
        ##
        # Dont send nginx version number
        ##
        server_tokens off;
        ##
        # Virtual Host Configs
        ##
        include /etc/nginx/conf.d/*.conf;
        include /etc/nginx/sites-enabled/*;
      }

  # Write reverse-proxy configuration file
  - path: /etc/nginx/sites-available/reverse-proxy.conf
    content: |
      # Listen on port 80
      server {
        listen 80;
        # Set your domain name
        server_name survey.metalisp.dev;
        # Redirect all requests to HTTPS
        return 301 https://$host$request_uri;
      }

      # Listen on port 443 with SSL
      server {
        listen 443 ssl;
        # Set your domain name
        server_name survey.metalisp.dev;

        # Include SSL certificate managed by Certbot
        ssl_certificate /etc/letsencrypt/live/survey.metalisp.dev/fullchain.pem;
        # Include SSL certificate key managed by Certbot
        ssl_certificate_key /etc/letsencrypt/live/survey.metalisp.dev/privkey.pem;
        # Include SSL options provided by Certbot
        include /etc/letsencrypt/options-ssl-nginx.conf;
        # Include DH parameters provided by Certbot
        ssl_dhparam /etc/letsencrypt/ssl-dhparams.pem;

        # Proxy settings for the location
        location / {
          # Set backend server address and port
          proxy_pass http://localhost:8080;
          # Set Host header
          proxy_set_header Host $host;
          # Set X-Real-IP header
          proxy_set_header X-Real-IP $remote_addr;
          # Set X-Forwarded-For header
          proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
          # Set X-Forwarded-Proto header
          proxy_set_header X-Forwarded-Proto $scheme;
        }
      }

  - path: /home/cl/setup_git.sh
    owner: 'cl:cl'
    permissions: '0755'
    defer: True
    content: |
      #!/bin/bash
      git config --global user.email "marcus.kammer@mailbox.org"
      git config --global user.name "Marcus Kammer"
      git config --global init.defaultBranch main

  - path: /home/cl/setup_repos.sh
    owner: 'cl:cl'
    permissions: '0755'
    defer: True
    content: |
      #!/bin/bash
      # Clone the SLIME repository for a specific branch and depth
      git clone --branch v2.9 https://github.com/slime/slime.git ~/slime

  - path: /home/cl/setup_user_all.sh
    owner: 'cl:cl'
    permissions: '0755'
    defer: True
    content: |
      #!/bin/bash
      /bin/bash /home/cl/setup_git.sh
      /bin/bash /home/cl/setup_repos.sh
      ssh-keygen -t ed25519 -C 'u1.metalisp' -f ~/.ssh/id_ed25519 -N ''
      mkdir -p ~/www/u1/docs/

  - path: /home/cl/openai_block_access.sh
    owner: 'cl:cl'
    permissions: '0755'
    defer: True
    content: |
      #!/bin/bash
      # Purpose: Block OpenAI ChatGPT bot CIDR
      # Tested on: Debian and Ubuntu Linux
      # Author: Vivek Gite {https://www.cyberciti.biz} under GPL v2.x+
      # ------------------------------------------------------------------
      file="/tmp/out.txt.$$"
      wget -q -O "$file" https://openai.com/gptbot-ranges.txt 2>/dev/null

      while IFS= read -r cidr
      do
          sudo ufw deny proto tcp from $cidr to any port 80
          sudo ufw deny proto tcp from $cidr to any port 443
      done < "$file"
      [ -f "$file" ] && rm -f "$file"

  - path: /home/cl/.tmux.conf
    owner: 'cl:cl'
    permissions: '0755'
    defer: True
    content: |
      # Improve colors and set TERM correctly inside tmux
      set -g default-terminal "screen-256color"

      # Set prefix key to Ctrl-a, like GNU Screen
      unbind C-b
      set -g prefix C-a
      bind C-a send-prefix

      # Enable mouse support
      set -g mouse on

      # Use Alt-arrow keys to switch panes
      bind -n M-Left select-pane -L
      bind -n M-Right select-pane -R
      bind -n M-Up select-pane -U
      bind -n M-Down select-pane -D

      # Use Alt+h/j/k/l to resize panes
      bind -n M-h resize-pane -L 2
      bind -n M-j resize-pane -D 2
      bind -n M-k resize-pane -U 2
      bind -n M-l resize-pane -R 2

      # Split panes with | and -
      bind | split-window -h
      bind - split-window -v

      # Reload tmux config
      bind r source-file ~/.tmux.conf

      # Quick pane cycling
      unbind ^A
      bind ^A select-pane -t :.+

      # Enable clipboard support on macOS
      # Uncomment the line below if you are on macOS and have reattach-to-user-namespace installed
      # set-option -g default-command "reattach-to-user-namespace -l $SHELL"

      # Increase history limit
      set -g history-limit 50000

      # One Dark theme specific settings

      # Status bar colors
      set -g status-bg colour235 # Base background color
      set -g status-fg colour137 # Base foreground color
      set -g status-interval 5
      set -g status-left "#[fg=colour81]#H " # Hostname in a different color
      set -g status-right "#[fg=colour137]#(date '+%Y-%m-%d %H:%M')" # Date and time

      # Active window in status bar
      setw -g window-status-current-style fg=colour125,bg=colour235,bold

      # Pane border
      set -g pane-border-style fg=colour238
      set -g pane-active-border-style fg=colour81

      # Message styling
      set -g message-style fg=colour166,bg=colour235

      # Window list - pane number (current and other)
      setw -g window-status-current-format "#[bold,fg=colour81]#I:#W#F"
      setw -g window-status-format "#[fg=colour137]#I:#W#F"

  - path: /home/cl/access_logs.sql
    owner: 'cl:cl'
    defer: True
    content: |
      -- Set the mode to CSV to properly import CSV files
      .mode csv

      -- If the table doesn't exist, create it
      CREATE TABLE IF NOT EXISTS access_logs (
        timestamp TEXT,
        ip_address TEXT,
        remote_user TEXT,
        request TEXT,
        status_code INTEGER,
        body_bytes_sent INTEGER,
        http_referer TEXT,
        http_user_agent TEXT
      );

      -- Import the data into the 'access_logs' table
      .import '/var/log/nginx/access.csv' access_logs

  - path: /home/cl/pihole_set_ufw.sh
    owner: 'cl:cl'
    permissions: '0755'
    defer: True
    content: |
      #!/bin/bash
      # Necessary pihole ufw setup
      sudo ufw allow 80/tcp
      sudo ufw allow 53/tcp
      sudo ufw allow 53/udp
      sudo ufw allow 67/tcp
      sudo ufw allow 67/udp
      sudo ufw allow 546:547/udp

  - path: /etc/sbclrc
    content: |
      ;;; -*- lisp -*-
      ;;; System-wide startup file for sbcl

      ;;; https://github.com/ghollisjr/sbcl-script
      ;;; If the first user-processable command-line argument is a filename,
      ;;; disable the debugger, load the file handling shebang-line and quit.
      (let ((script (and (second *posix-argv*)
                         (probe-file (second *posix-argv*)))))
         (when script
            ;; Handle shebang-line
            (set-dispatch-macro-character #\# #\!
                                          (lambda (stream char arg)
                                             (declare (ignore char arg))
                                             (read-line stream)))
            ;; Disable debugger
            (setf *invoke-debugger-hook*
                  (lambda (condition hook)
                    (declare (ignore hook))
                    ;; Uncomment to get backtraces on errors
                    ;; (sb-debug:backtrace 20)
                    (format *error-output* "Error: ~A~%" condition)
                    (quit)))
            (load script)
            (quit)))

      (defun print-condition-hook (condition hook)
        "This function is designed to be used as a custom debugger hook.
        It prints the condition (error message), clears any remaining input,
        and aborts the current operation."
        ;; Ignore the hook argument since it's not used in this function.
        (declare (ignore hook))

        ;; Print the error message associated with the condition.
        (princ condition)

        ;; Clear any pending input from the stream.
        (clear-input)

        ;; Abort the current operation and return to the top-level.
        (abort))

      ;; Get the value of the global variable *debugger-hook*.
      *debugger-hook*

      ;; Set the global variable *debugger-hook* to the custom debugger hook
      ;; function 'print-condition-hook'. This function will now be called
      ;; whenever an unhandled error occurs.
      (setf *debugger-hook* #'print-condition-hook)

  - path: /home/cl/.sbclrc
    owner: 'cl:cl'
    defer: True
    content: |
      ;;; -*- lisp -*-
      (sb-ext:set-sbcl-source-location #P"~/sbcl/")

  - path: /home/cl/lisp_01_setup_sbcl.sh
    owner: 'cl:cl'
    permissions: '0755'
    defer: True
    content: |
      #!/bin/bash
      # Exit on error
      set -e
      sudo apt update
      sudo apt install -y sbcl git libzstd-dev
      # Download SBCL source
      # wget http://prdownloads.sourceforge.net/sbcl/sbcl-2.3.10-source.tar.bz2
      # Extract it
      # tar -xjf sbcl-2.3.10-source.tar.bz2
      git clone --branch sbcl-2.4.2 git://git.code.sf.net/p/sbcl/sbcl ~/sbcl
      # Change into the directory
      cd sbcl
      # Compile and install
      sh make.sh --fancy
      sudo sh install.sh
      # Remove ubuntu specific sbcl
      sudo apt remove sbcl -y
      cd ~/ && sbcl --version

  - path: /home/cl/lisp_02_setup_quicklisp.sh
    owner: 'cl:cl'
    permissions: '0755'
    defer: True
    content: |
      #!/bin/bash
      # Needs to be run manually, cant be run automatically.
      # If runs automatically, `quicklisp.lisp' cant be find by sbcl.
      sudo apt install -y libev4 libsqlite3-dev
      curl https://beta.quicklisp.org/quicklisp.lisp -o ~/quicklisp.lisp
      sbcl --noinform --load quicklisp.lisp --eval "(quicklisp-quickstart:install)" --eval "(ql-util:without-prompting (ql:add-to-init-file))" --non-interactive
      sbcl --noinform --eval "(ql:quickload '(:hunchentoot :spinneret))" --non-interactive

  - path: /home/cl/lisp_03_load_swank_faster.lisp
    owner: 'cl:cl'
    defer: True
    content: |
      ;;;; This Common Lisp script sets up a development environment by loading essential
      ;;;; libraries for web development and data handling, including SBCL system
      ;;;; libraries and external tools via Quicklisp. It concludes by saving the
      ;;;; environment state to a core file for efficient reusability in future sessions.
      (mapc 'require '(sb-bsd-sockets sb-posix sb-introspect sb-cltl2 asdf))
      (ql:quickload '(:hunchentoot :spinneret))
      (save-lisp-and-die "sbcl.core-for-slime")

  - path: /home/cl/lisp_03_load_swank_faster.sh
    owner: 'cl:cl'
    permissions: '0755'
    defer: True
    content: |
      #!/bin/bash
      sbcl --noinform --noprint --load ~/lisp_03_load_swank_faster.lisp

runcmd:
  # Run Certbot to obtain SSL certificates and configure Nginx
  - certbot certonly --nginx -d survey.metalisp.dev --non-interactive --agree-tos --email marcus.kammer@metalisp.dev --redirect
  - certbot certonly --nginx -d survey.u1.metalisp.dev --non-interactive --agree-tos --email marcus.kammer@metalisp.dev --redirect
  # Add cron job for automatic certificate renewal (runs once a month)
  - echo '0 0 1 * * root certbot renew --post-hook "systemctl reload nginx" >> /var/log/letsencrypt/letsencrypt-auto-renew.log' > /etc/cron.d/letsencrypt-renew
  # Download DHPARAM

  # The Diffie-Hellman algorithm is used to establish a shared secret between two
  # parties (typically a client and a server) over a public channel, and is a
  # fundamental part of many cryptographic protocols, including HTTPS.

  # However, generating Diffie-Hellman parameters can be computationally expensive,
  # so pre-generated parameters are often used. Mozilla provides such pre-generated
  # parameters, and they are considered to be trustworthy.

  # The downloaded parameters are saved in a file named ssl-dhparam.pem in the
  # /etc/letsencrypt directory. This file is then referenced in the configuration
  # of services that use Diffie-Hellman key exchange, such as your Nginx server, to
  # establish secure communications.

  # This step is part of a broader effort to set up SSL/TLS securely on your
  # server, enhancing the security of your connections.

  - curl https://ssl-config.mozilla.org/ffdhe2048.txt > /etc/letsencrypt/ssl-dhparam.pem
  # Create a symlink for the configuration file
  - ln -s /etc/nginx/sites-available/reverse-proxy.conf /etc/nginx/sites-enabled/
  # Remove default Nginx configuration
  - rm /etc/nginx/sites-enabled/default
  # Reload Nginx configuration
  - systemctl reload nginx
  # Allow Nginx Full (HTTP and HTTPS) through the firewall
  - ufw allow 'Nginx Full'
  # Set UFW firewall rules
  - ufw default deny incoming
  - ufw default allow outgoing
  - ufw allow 22/tcp
  - ufw allow mosh
  - ufw enable
  # Enable and start the fail2ban service
  - systemctl enable fail2ban && systemctl start fail2ban
  # Restart the SSH server to apply the new configuration
  - systemctl restart sshd
  - sudo -u cl /bin/bash /home/cl/setup_user_all.sh