wireguard: use vpn for bastion-fleet comms

supposedly fleet will be more secure this way

README.md

@@ -32,6 +32,8 @@ The playbook assumes fresh Arch Linux ARM images installed on machines in your L
 They should start off with default credentials (i.e. `alarm:alarm`, `root:root`).
 This repo takes care of everything else.
 The intended topology is a bastion host facing the Internet, with reverse proxies forwarding traffic to a service host inside the firewall.
+The servers are all on a WireGuard network.
+This network also serves as the typical "encrypted tunnel" for devices on the go.
 
 - Flash all your machines with Arch Linux ARM.
 - Copy `inventory.example.yml` to `inventory.yml`.

group_vars/all/00-secret_template.yml

@@ -28,14 +28,20 @@ form_secret: ""
 paperless_secret: ""
 
 wireguard_secret:
-  # server secret
+  # server secrets
   # generate with `wg genkey`, available in the 'wireguard-tools' package
-  server_key: ""
-  # pipe the secret key (see secret_template in group_vars/) into `wg pubkey` to get this
-  server_pub_key: ""
+  servers:
+    your_bastion_host:
+      # see inventory.yml to set the vpn address
+      priv: ""
+      # pipe the secret key (see secret_template in group_vars/) into `wg pubkey` to get this
+      pub: ""
+    your_fleet_host:
+      priv: ""
+      pub: ""
 
-  # list of clients to generate configs for
-  peers:
+  # list of clients to generate configs for on the bastion host
+  clients:
     # name of the client
     - name: test_client
       addr: "10.66.77.2"

group_vars/all/50-vars.yml

@@ -43,3 +43,6 @@ escalation_method: doas
 
 # set up static IP
 enable_connection: yes
+
+# use a wireguard network between bastion and fleet host for the reverse proxy
+wireguard_services: true

inventory.example.yml

@@ -3,7 +3,10 @@
 
 # fallback_host is only used during setup before the static IP (local_ip) is configured.
 # Set fallback_host using `nmap 192.168.0.0/24 -p 22` to find the dynamic IP of your Pi
+#
 # local_ip is used after first setup.
+#
+# vpn_ip is used for the WireGuard network.
 
 # Make entries in your .ssh/config for ease of use
 # Example:
@@ -19,6 +22,7 @@ all:
     your_bastion_host:
       fallback_host: 192.168.0.123
       local_ip: 192.168.0.3
+      vpn_ip: 10.66.77.1
       ansible_port: 2500
       ansible_connection: ssh
       ansible_ssh_private_key_file: ~/.ssh/keys/your_bastion_host
@@ -26,6 +30,7 @@ all:
     your_fleet_host:
       fallback_host: 192.168.0.124
       local_ip: 192.168.0.86
+      vpn_ip: 10.66.77.86
       ansible_port: 2500
       ansible_connection: ssh
       ansible_ssh_private_key_file: ~/.ssh/keys/your_fleet_host
@@ -65,6 +70,7 @@ all:
     wireguard:
       hosts:
         your_bastion_host:
+        your_fleet_host:
     sshd:
       hosts:
         your_bastion_host:

roles/containers/tasks/main.yml

@@ -126,6 +126,10 @@
   register: user_synapse
   when: '"synapse" in groups'
 
+- name: Figure out local IP address
+  set_fact:
+    docker_ip: "{{ vpn_ip if wireguard_services else local_ip }}"
+
 - name: Generate docker-compose.yml
   template:
     src: "docker-compose.yml.j2"

roles/containers/templates/docker-compose.yml.j2

@@ -1,8 +1,6 @@
 # vim: ft=yaml
 ---
 
-version: "3"
-
 networks:
   gitea:
     driver: bridge
@@ -22,8 +20,8 @@ services:
       - GITEA__server__DOMAIN={{ gitea_domain }}
       - GITEA__server__SSH_DOMAIN={{ gitea_domain }}
     ports:
-      - "3000:3000"
-      - "2498:22"
+      - "{{ docker_ip }}:3000:3000"
+      - "{{ docker_ip }}:2498:22"
     restart: unless-stopped
     volumes:
       - {{ dataroot }}/gitea:/data
@@ -65,7 +63,7 @@ services:
     networks:
       - navidrome
     ports:
-      - "4533:4533"
+      - "{{ docker_ip }}:4533:4533"
 
 {% endif %}
 {% if "synapse" in group_names %}
@@ -82,7 +80,7 @@ services:
     networks:
       - navidrome
     ports:
-      - "8008:8008/tcp"
+      - "{{ docker_ip }}:8008:8008/tcp"
 
 {% endif %}
 
@@ -101,7 +99,7 @@ services:
     depends_on:
       - paperless-broker
     ports:
-      - "8000:8000"
+      - "{{ docker_ip }}:8000:8000"
     healthcheck:
       test: ["CMD", "curl", "-fs", "-S", "--max-time", "2", "http://localhost:8000"]
       interval: 30s

roles/firewall/defaults/main.yml

@@ -8,3 +8,4 @@ local_subnet: 192.168.0.0/24
 sshd_port: 2500
 
 bastion_ip: "{{ hostvars[groups['bastion'][0]]['local_ip'] }}"
+bastion_vpn_ip: "{{ hostvars[groups['bastion'][0]]['vpn_ip'] }}"

roles/firewall/tasks/main.yml

@@ -14,9 +14,10 @@
 
 - name: Set default sources (fleet server)
   set_fact:
-    default_firewall_src: "{{ bastion_ip }}"
+    default_firewall_src: "{{ bastion_vpn_ip if wireguard_services else bastion_ip }}"
   when: '"fleet" in group_names'
 
+# this is actually kind of useless because docker bypasses this
 - name: Allow service ports
   community.general.ufw:
     rule: allow

roles/networking/hosts/templates/hosts.j2

@@ -5,5 +5,9 @@
 # Modifications will be lost!
 
 {% for host in groups["all"] %}
+{% if wireguard_services %}
+{{ hostvars[host]["vpn_ip"] }} {{ host }}
+{% else %}
 {{ hostvars[host]["local_ip"] }} {{ host }}
+{% endif %}
 {% endfor %}

roles/wireguard/defaults/main.yml

@@ -11,8 +11,6 @@ wireguard:
     - "{{ dns_forward }}"
   interface: "wg0"
   ip:
-    # address for the server
-    address: "10.66.77.1/32"
     # cidr range in tunnel
     cidr: "10.66.77.0/24"
 

roles/wireguard/tasks/main.yml

@@ -15,6 +15,7 @@
     value: 1
     state: present
     reload: yes
+  when: '"bastion" in group_names'
 
 - name: Setup UFW rules to accept VPN traffic
   community.general.ufw:
@@ -22,6 +23,7 @@
     direction: in
     src: "{{ wireguard.ip.cidr }}"
     dest: any
+  when: '"bastion" in group_names'
 
 - name: Deploy wireguard server config
   template:
@@ -42,6 +44,7 @@
     group: root
     mode: 0700
     state: directory
+  when: '"bastion" in group_names'
 
 - name: Create wireguard client configs
   template:
@@ -52,6 +55,7 @@
     mode: 0600
     lstrip_blocks: true
   no_log: true
-  with_items: "{{ wireguard_secret.peers }}"
+  with_items: "{{ wireguard_secret.clients }}"
   notify:
     - Start wireguard
+  when: '"bastion" in group_names'

roles/wireguard/templates/client.conf.j2

@@ -3,14 +3,12 @@
 Address = {{ item.addr }}
 # device privkey
 PrivateKey = {{ item.priv_key }}
-DNS = {{ wireguard.ip.address }}
+DNS = {{ hostvars[groups["bastion"][0]].vpn_ip }}
 
 [Peer]
 # server stuff
-PublicKey = {{ wireguard_secret.server_pub_key }}
+PublicKey = {{ wireguard_secret.servers[groups["bastion"][0]].pub }}
 Endpoint = {{ wireguard.ip.server_public }}:{{ wireguard.ip.port }}
 
 # allow traffic for all subnets into the VPN
 AllowedIPs = 0.0.0.0/0
-
-PersistentKeepalive = 25

roles/wireguard/templates/server.conf.j2

@@ -1,14 +1,27 @@
 [Interface]
-Address = {{ wireguard.ip.address }}
-PrivateKey = {{ wireguard_secret.server_key }}
+Address = {{ hostvars[inventory_hostname]["vpn_ip"] }}/32
+PrivateKey = {{ wireguard_secret.servers[inventory_hostname].priv }}
 ListenPort = {{ wireguard.ip.port }}
 
+{% if "bastion" in group_names %}
 PostUp = iptables -A FORWARD -i %i -j ACCEPT; iptables -t nat -A POSTROUTING -o {{ net_interface }} -j MASQUERADE
 PostDown = iptables -D FORWARD -i %i -j ACCEPT; iptables -t nat -A POSTROUTING -o {{ net_interface }} -j MASQUERADE
+{% endif %}
 SaveConfig = false
 
-{% for peer in wireguard_secret.peers %}
+{% for server_peer in wireguard_secret.servers %}
+{% if not server_peer == inventory_hostname %}
+[Peer]
+PublicKey = {{ wireguard_secret.servers[server_peer].pub }}
+AllowedIPs = {{ hostvars[server_peer]["vpn_ip"] }}
+Endpoint = {{ hostvars[server_peer]["local_ip"] }}:{{ wireguard.ip.port }}
+{% endif %}
+{% endfor %}
+
+{% if "bastion" in group_names %}
+{% for peer in wireguard_secret.clients %}
 [Peer]
 PublicKey = {{ peer.pub_key }}
 AllowedIPs = {{ peer.addr }}
 {% endfor %}
+{% endif %}