---
# ============================================================================
# Road-warrior OpenVPN профиль для телефона (Android).
#
# Отдельный TLS point-to-point инстанс на ru-vps (порт 9444/tcp, tun2,
# сеть 10.80.0.0/30), параллельный тоннелю site-to-site (tun0, homelab-openvpn)
# и профилю ноутбука (tun1, openvpn-laptop.yml). Клиент подключается один за
# раз.
#
# КРИПТО: peer-fingerprint, БЕЗ CA/PKI.
#   На ru-vps генерятся две самоподписанные EC-пары (server.* и client.*),
#   каждая сторона пинит другую по SHA256-отпечатку. Это «quick setup»
#   из man-страницы OpenVPN 2.6+. Прежняя схема со static key (--secret)
#   отброшена: OpenVPN 2.7 в Android-клиенте запускать её отказывается
#   ("No tls-client or tls-server option"), а 2.8 уберёт совсем.
#
# КЛИЕНТ
#   Android — «OpenVPN for Android» (Arne Schwabe) или OpenVPN Connect:
#   TLS-конфиг понимают оба. Профиль самодостаточный (cert+key внутри).
#
# ЧТО ДЕЛАЕТ
#   Ставит openvpn на ru-vps, генерит EC-пары (один раз), открывает
#   9444/tcp в UFW, поднимает systemd-юнит homelab-openvpn-phone, NAT'ит
#   10.80.0.0/30 -> LAN через tun0, кладёт готовый профиль в
#   ansible/generated/ada-phone.ovpn (mode 0600, содержит приватный ключ).
#
# ЗАПУСК
#   make openvpn-phone
# ============================================================================
- name: Configure OpenVPN phone access through ru-vps
  hosts: ru-vps
  gather_facts: true
  become: true
  vars:
    phone_profile_name: ada-phone
    phone_openvpn_dir: /etc/openvpn/homelab-phone
    phone_openvpn_config: /etc/openvpn/homelab-phone/server.conf
    phone_openvpn_server_cert: /etc/openvpn/homelab-phone/server.crt
    phone_openvpn_server_key: /etc/openvpn/homelab-phone/server.key
    phone_openvpn_client_cert: /etc/openvpn/homelab-phone/client.crt
    phone_openvpn_client_key: /etc/openvpn/homelab-phone/client.key
    phone_openvpn_service: homelab-openvpn-phone
    phone_openvpn_port: 9444
    phone_openvpn_interface: tun2
    phone_openvpn_site_interface: tun0
    phone_openvpn_network_cidr: 10.80.0.0/30
    phone_openvpn_server_ip: 10.80.0.1
    phone_openvpn_client_ip: 10.80.0.2
    phone_openvpn_remote: 157.22.231.198
    phone_openvpn_data_ciphers: "AES-256-GCM:AES-128-GCM"
    phone_openvpn_client_config_local: "{{ playbook_dir }}/../generated/{{ phone_profile_name }}.ovpn"
    phone_openvpn_routes: "{{ homelab_vpn_client_routes }}"

  tasks:
    - name: Install OpenVPN packages
      ansible.builtin.apt:
        name:
          - openvpn
          - iptables
          - openssl
        state: present
        update_cache: true

    - name: Ensure phone OpenVPN config directory exists
      ansible.builtin.file:
        path: "{{ phone_openvpn_dir }}"
        state: directory
        owner: root
        group: root
        mode: "0700"

    - name: Remove the obsolete static key (crypto model changed to TLS)
      ansible.builtin.file:
        path: "{{ phone_openvpn_dir }}/static.key"
        state: absent

    - name: Generate the server EC keypair if missing
      ansible.builtin.command:
        argv:
          - openssl
          - req
          - -x509
          - -newkey
          - ec
          - -pkeyopt
          - ec_paramgen_curve:prime256v1
          - -keyout
          - "{{ phone_openvpn_server_key }}"
          - -out
          - "{{ phone_openvpn_server_cert }}"
          - -nodes
          - -sha256
          - -days
          - "3650"
          - -subj
          - /CN=homelab-phone-server
      args:
        creates: "{{ phone_openvpn_server_cert }}"
      no_log: true

    - name: Generate the client EC keypair if missing
      ansible.builtin.command:
        argv:
          - openssl
          - req
          - -x509
          - -newkey
          - ec
          - -pkeyopt
          - ec_paramgen_curve:prime256v1
          - -keyout
          - "{{ phone_openvpn_client_key }}"
          - -out
          - "{{ phone_openvpn_client_cert }}"
          - -nodes
          - -sha256
          - -days
          - "3650"
          - -subj
          - /CN=homelab-phone-client
      args:
        creates: "{{ phone_openvpn_client_cert }}"
      no_log: true

    - name: Enforce key permissions
      ansible.builtin.file:
        path: "{{ item }}"
        owner: root
        group: root
        mode: "0600"
      loop:
        - "{{ phone_openvpn_server_key }}"
        - "{{ phone_openvpn_client_key }}"

    - name: Read the server certificate fingerprint
      ansible.builtin.command:
        argv:
          - openssl
          - x509
          - -in
          - "{{ phone_openvpn_server_cert }}"
          - -noout
          - -fingerprint
          - -sha256
      register: phone_openvpn_server_fp_raw
      changed_when: false

    - name: Read the client certificate fingerprint
      ansible.builtin.command:
        argv:
          - openssl
          - x509
          - -in
          - "{{ phone_openvpn_client_cert }}"
          - -noout
          - -fingerprint
          - -sha256
      register: phone_openvpn_client_fp_raw
      changed_when: false

    - name: Extract the bare colon-separated fingerprints
      # openssl печатает "sha256 Fingerprint=AB:CD:...", отпечаток без '='.
      ansible.builtin.set_fact:
        phone_openvpn_server_fp: "{{ phone_openvpn_server_fp_raw.stdout | regex_replace('^.*=', '') | trim }}"
        phone_openvpn_client_fp: "{{ phone_openvpn_client_fp_raw.stdout | regex_replace('^.*=', '') | trim }}"

    - name: Enable IPv4 forwarding on ru-vps
      ansible.posix.sysctl:
        name: net.ipv4.ip_forward
        value: "1"
        state: present
        reload: true

    - name: Allow phone OpenVPN TCP in UFW
      ansible.builtin.command: "ufw allow {{ phone_openvpn_port }}/tcp"
      register: ufw_allow_phone_openvpn
      changed_when: "'Rule added' in ufw_allow_phone_openvpn.stdout or 'Rules updated' in ufw_allow_phone_openvpn.stdout"
      failed_when: false

    # Road-warrior трафик tun2 -> tun0 ФОРВАРДИТСЯ через ru-vps, а policy
    # FORWARD = DROP. Сайт-тоннель этого правила не требовал (он несёт
    # собственный трафик ru-vps, не forward). ufw route allow переживает
    # `ufw reload`, в отличие от сырого iptables -I FORWARD. Обратное
    # направление покрыто глобальным RELATED,ESTABLISHED в ufw-before-forward.
    - name: Allow forwarding phone VPN traffic into the LAN
      community.general.ufw:
        route: true
        rule: allow
        interface_in: "{{ phone_openvpn_interface }}"
        interface_out: "{{ phone_openvpn_site_interface }}"
        src: "{{ phone_openvpn_network_cidr }}"
        dest: "{{ homelab_lan_cidr }}"

    - name: Render phone OpenVPN server config
      ansible.builtin.copy:
        dest: "{{ phone_openvpn_config }}"
        owner: root
        group: root
        mode: "0600"
        content: |
          dev {{ phone_openvpn_interface }}
          dev-type tun
          ifconfig {{ phone_openvpn_server_ip }} {{ phone_openvpn_client_ip }}
          proto tcp-server
          port {{ phone_openvpn_port }}
          tls-server
          dh none
          cert {{ phone_openvpn_server_cert }}
          key {{ phone_openvpn_server_key }}
          peer-fingerprint {{ phone_openvpn_client_fp }}
          data-ciphers {{ phone_openvpn_data_ciphers }}
          auth SHA256
          persist-key
          persist-tun
          keepalive 10 60
          verb 3
      notify: restart phone openvpn

    - name: Render phone OpenVPN up script
      ansible.builtin.copy:
        dest: "{{ phone_openvpn_dir }}/up.sh"
        owner: root
        group: root
        mode: "0700"
        content: |
          #!/bin/sh
          iptables -t nat -C POSTROUTING -s {{ phone_openvpn_network_cidr }} -d {{ homelab_lan_cidr }} -o {{ phone_openvpn_site_interface }} -j MASQUERADE 2>/dev/null || \
            iptables -t nat -A POSTROUTING -s {{ phone_openvpn_network_cidr }} -d {{ homelab_lan_cidr }} -o {{ phone_openvpn_site_interface }} -j MASQUERADE
      notify: restart phone openvpn

    - name: Render phone OpenVPN down script
      ansible.builtin.copy:
        dest: "{{ phone_openvpn_dir }}/down.sh"
        owner: root
        group: root
        mode: "0700"
        content: |
          #!/bin/sh
          iptables -t nat -D POSTROUTING -s {{ phone_openvpn_network_cidr }} -d {{ homelab_lan_cidr }} -o {{ phone_openvpn_site_interface }} -j MASQUERADE 2>/dev/null || true
      notify: restart phone openvpn

    - name: Render phone OpenVPN systemd service
      ansible.builtin.copy:
        dest: "/etc/systemd/system/{{ phone_openvpn_service }}.service"
        owner: root
        group: root
        mode: "0644"
        content: |
          [Unit]
          Description=HomeLab OpenVPN phone access
          After=network-online.target homelab-openvpn.service
          Wants=network-online.target
          Requires=homelab-openvpn.service

          [Service]
          Type=simple
          ExecStartPre={{ phone_openvpn_dir }}/up.sh
          ExecStart=/usr/sbin/openvpn --config {{ phone_openvpn_config }}
          ExecStopPost={{ phone_openvpn_dir }}/down.sh
          Restart=on-failure
          RestartSec=5

          [Install]
          WantedBy=multi-user.target
      notify:
        - reload systemd
        - restart phone openvpn

    - name: Flush handlers before starting phone OpenVPN
      ansible.builtin.meta: flush_handlers

    - name: Enable and start phone OpenVPN
      ansible.builtin.systemd:
        name: "{{ phone_openvpn_service }}"
        state: started
        enabled: true

    - name: Read the client certificate for the profile
      ansible.builtin.slurp:
        src: "{{ phone_openvpn_client_cert }}"
      register: phone_openvpn_client_cert_raw
      no_log: true

    - name: Read the client key for the profile
      ansible.builtin.slurp:
        src: "{{ phone_openvpn_client_key }}"
      register: phone_openvpn_client_key_raw
      no_log: true

    - name: Ensure local generated directory exists
      ansible.builtin.file:
        path: "{{ playbook_dir }}/../generated"
        state: directory
        mode: "0700"
      delegate_to: localhost
      vars:
        ansible_connection: local
        ansible_become: false

    - name: Write local phone OpenVPN profile
      ansible.builtin.copy:
        dest: "{{ phone_openvpn_client_config_local }}"
        mode: "0600"
        content: |
          dev tun
          dev-type tun
          proto tcp-client
          remote {{ phone_openvpn_remote }} {{ phone_openvpn_port }}
          ifconfig {{ phone_openvpn_client_ip }} {{ phone_openvpn_server_ip }}
          tls-client
          peer-fingerprint {{ phone_openvpn_server_fp }}
          data-ciphers {{ phone_openvpn_data_ciphers }}
          auth SHA256
          persist-key
          persist-tun
          resolv-retry infinite
          nobind
          verb 3
          {% for route in phone_openvpn_routes %}
          route {{ route.network }} {{ route.netmask }}
          {% endfor %}
          <cert>
          {{ phone_openvpn_client_cert_raw.content | b64decode | trim }}
          </cert>
          <key>
          {{ phone_openvpn_client_key_raw.content | b64decode | trim }}
          </key>
      delegate_to: localhost
      vars:
        ansible_connection: local
        ansible_become: false
      no_log: true

  handlers:
    - name: reload systemd
      ansible.builtin.systemd:
        daemon_reload: true

    - name: restart phone openvpn
      ansible.builtin.systemd:
        name: "{{ phone_openvpn_service }}"
        state: restarted