From 7221496f0555bbdd1601ea70da2a9ca99cd34488 Mon Sep 17 00:00:00 2001 From: Ahmed Abdelhalim Date: Wed, 3 Sep 2025 02:26:21 +0200 Subject: Refactor: rename wireguard_gateway to gateway As the role now functions as a gateway and not just a wireguard gateway it's better name for clarity --- roles/gateway/README.md | 98 +++++++++++++++++++++++++++++ roles/gateway/defaults/main.yml | 2 + roles/gateway/handlers/main.yml | 6 ++ roles/gateway/meta/argument_specs.yml | 10 +++ roles/gateway/meta/main.yml | 20 ++++++ roles/gateway/tasks/main.yml | 112 ++++++++++++++++++++++++++++++++++ 6 files changed, 248 insertions(+) create mode 100644 roles/gateway/README.md create mode 100644 roles/gateway/defaults/main.yml create mode 100644 roles/gateway/handlers/main.yml create mode 100644 roles/gateway/meta/argument_specs.yml create mode 100644 roles/gateway/meta/main.yml create mode 100644 roles/gateway/tasks/main.yml (limited to 'roles/gateway') diff --git a/roles/gateway/README.md b/roles/gateway/README.md new file mode 100644 index 00000000..54c45430 --- /dev/null +++ b/roles/gateway/README.md @@ -0,0 +1,98 @@ +# Ansible Role: gateway + +This role configures a Linux host as a gateway, +routing all traffic from local network clients through. + +## Role Variables + +- `gateway_enabled`: Boolean flag to enable/disable gateway functionality (default: `false`) + +## What This Role Does + +When `gateway_enabled` is `true`, the role: + +- Sets `net.ipv4.ip_forward=1` and `net.ipv6.conf.all.forwarding=1` in `/etc/sysctl.conf` +- Creates custom routing table (100) to route traffic through VPN +- Routes IPv4 and IPv6 traffic from local subnet through VPN interface +- Allows traffic forwarding and established connections + +When `gateway_enabled` is `false`, the role: + +- Removes all routing rules and iptables configurations +- Disables IP forwarding in sysctl configuration +- Cleans up custom routing tables + +## Example Configuration + +```yaml +# In host_vars/rpi5.local.yml +gateway_enabled: true +wireguard_autostart_connection: "protonvpn-us1" + +# WireGuard connection configuration +wireguard_connections: + protonvpn-us1: | + [Interface] + PrivateKey = your_private_key_here + Address = 10.2.0.2/32 + DNS = 10.2.0.1 + + [Peer] + PublicKey = server_public_key + AllowedIPs = 0.0.0.0/0, ::/0 + Endpoint = vpn.example.com:51820 +``` + +## Client Configuration + +For client machines to route through the VPN gateway: + +1. **IPv4**: Set gateway to VPN gateway host's IP +2. **IPv6**: Set IPv6 gateway to VPN gateway host's IPv6 address +3. **Manual network config**: Disable auto-configuration to use custom gateway + +Example client network configuration: + +```yaml +network_ipv4_address: "192.168.1.100" +network_ipv4_gateway: "192.168.1.254" # VPN gateway host +network_ipv6_address: "2001:db8::100/64" +network_ipv6_gateway: "2001:db8::254" # VPN gateway host +``` + +## Technical Details + +### Routing Rules Created + +```bash +# Policy routing rules (priority 200) +ip rule add iif eth0 table 100 priority 200 +ip -6 rule add iif eth0 table 100 priority 200 + +# Custom routing table (table 100) +ip route add default dev wg-connection table 100 +ip -6 route add default dev wg-connection table 100 +``` + +### iptables Rules Created + +```bash +# IPv4 NAT masquerading +iptables -t nat -A POSTROUTING -s 192.168.1.0/24 -o wg-connection -j MASQUERADE + +# IPv4 FORWARD rules +iptables -A FORWARD -s 192.168.1.0/24 -j ACCEPT +iptables -A FORWARD -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT + +# IPv6 equivalent rules +ip6tables -t nat -A POSTROUTING -s 2001:db8::/64 -o wg-connection -j MASQUERADE +ip6tables -A FORWARD -s 2001:db8::/64 -j ACCEPT +ip6tables -A FORWARD -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT +``` + +## Troubleshooting + +- **Check VPN connection**: `sudo wg show` should show active connection +- **Verify routing**: `ip rule show` and `ip route show table 100` +- **Test connectivity**: `curl ip.me` should show VPN IP from client machines +- **Check iptables**: `sudo iptables -t nat -L -n -v` should show masquerading rules diff --git a/roles/gateway/defaults/main.yml b/roles/gateway/defaults/main.yml new file mode 100644 index 00000000..8cddb272 --- /dev/null +++ b/roles/gateway/defaults/main.yml @@ -0,0 +1,2 @@ +--- +gateway_enabled: false diff --git a/roles/gateway/handlers/main.yml b/roles/gateway/handlers/main.yml new file mode 100644 index 00000000..4b7cb2f2 --- /dev/null +++ b/roles/gateway/handlers/main.yml @@ -0,0 +1,6 @@ +--- +- name: "Reload sysctl" + become: true + ansible.builtin.command: + cmd: "sysctl -p" + changed_when: false diff --git a/roles/gateway/meta/argument_specs.yml b/roles/gateway/meta/argument_specs.yml new file mode 100644 index 00000000..d6520641 --- /dev/null +++ b/roles/gateway/meta/argument_specs.yml @@ -0,0 +1,10 @@ +--- +argument_specs: + main: + description: "Configure the PI as a network gateway forcing all traffic through it (or through active VPN on it)" + author: "a14m" + options: + gateway_enabled: + description: "Toggle flag for enabling/disabling network gateway configurations" + type: "bool" + default: false diff --git a/roles/gateway/meta/main.yml b/roles/gateway/meta/main.yml new file mode 100644 index 00000000..36df4aad --- /dev/null +++ b/roles/gateway/meta/main.yml @@ -0,0 +1,20 @@ +--- +dependencies: + - "wireguard" + +galaxy_info: + author: "a14m" + description: "Install and configure WireGuard VPN as a network gateway" + company: "kartoffeln.work GmbH." + license: "MIT" + min_ansible_version: "2.18" + platforms: + - name: "ArchLinux" + versions: + - "all" + - name: "Ubuntu" + versions: + - "noble" + - name: "Debian" + versions: + - "bookworm" diff --git a/roles/gateway/tasks/main.yml b/roles/gateway/tasks/main.yml new file mode 100644 index 00000000..f9ccd4cb --- /dev/null +++ b/roles/gateway/tasks/main.yml @@ -0,0 +1,112 @@ +--- +- name: "Ensure iptables are installed" + become: true + ansible.builtin.package: + name: "iptables" + state: "present" + +- name: "Configure IP forwarding" + become: true + ansible.builtin.blockinfile: + path: "/etc/sysctl.conf" + state: "{{ 'present' if gateway_enabled else 'absent' }}" + prepend_newline: true + append_newline: true + marker: "# ==== {mark} ANSIBLE GATEWAY CONFIG" + create: true + mode: "0644" + block: | + net.ipv4.ip_forward=1 + net.ipv6.conf.all.forwarding=1 + notify: "Reload sysctl" + +# IPv4 iptables rules +- name: "Add IPv4 NAT masquerading for traffic through internet" + become: true + ansible.builtin.iptables: + table: "nat" + chain: "POSTROUTING" + source: "{{ (ansible_default_ipv4.address.split('.')[0:3] | join('.')) }}.0/24" + out_interface: "{{ ansible_default_ipv4.interface }}" + jump: "MASQUERADE" + comment: "NAT local subnet traffic through internet" + state: "present" + +- name: "Add IPv4 NAT masquerading for traffic through VPN" + become: true + ansible.builtin.iptables: + table: "nat" + chain: "POSTROUTING" + source: "{{ (ansible_default_ipv4.address.split('.')[0:3] | join('.')) }}.0/24" + out_interface: "{{ item }}" + jump: "MASQUERADE" + comment: "NAT local subnet traffic through VPN" + state: "{{ 'present' if gateway_enabled else 'absent' }}" + with_items: "{{ wireguard_connections }}" + +- name: "Add IPv4 FORWARD rule to accept traffic from local subnet" + become: true + ansible.builtin.iptables: + chain: "FORWARD" + source: "{{ (ansible_default_ipv4.address.split('.')[0:3] | join('.')) }}.0/24" + jump: "ACCEPT" + comment: "Allow forwarding from local subnet" + state: "{{ 'present' if gateway_enabled else 'absent' }}" + +- name: "Add IPv4 FORWARD rule to accept established connections" + become: true + ansible.builtin.iptables: + chain: "FORWARD" + match: "conntrack" + ctstate: "RELATED,ESTABLISHED" + jump: "ACCEPT" + comment: "Allow established connections" + state: "{{ 'present' if gateway_enabled else 'absent' }}" + +# IPv6 iptables rules +- name: "Add IPv6 NAT masquerading for traffic through internet" + become: true + ansible.builtin.iptables: + table: "nat" + chain: "POSTROUTING" + source: "{{ (ansible_default_ipv6.address.split(':')[:4] | join(':')) + '::/64' }}" + out_interface: "{{ ansible_default_ipv6.interface }}" + jump: "MASQUERADE" + comment: "NAT IPv6 local subnet traffic through internet" + ip_version: "ipv6" + state: "present" + when: ansible_default_ipv6.address is defined + +- name: "Add IPv6 NAT masquerading for traffic through VPN" + become: true + ansible.builtin.iptables: + table: "nat" + chain: "POSTROUTING" + source: "{{ (ansible_default_ipv6.address.split(':')[:4] | join(':')) + '::/64' }}" + out_interface: "{{ item }}" + jump: "MASQUERADE" + comment: "NAT IPv6 local subnet traffic through VPN" + ip_version: "ipv6" + state: "{{ 'present' if gateway_enabled else 'absent' }}" + with_items: "{{ wireguard_connections }}" + +- name: "Add IPv6 FORWARD rule to accept traffic from local subnet" + become: true + ansible.builtin.iptables: + chain: "FORWARD" + source: "{{ (ansible_default_ipv6.address.split(':')[:4] | join(':')) + '::/64' }}" + jump: "ACCEPT" + comment: "Allow IPv6 forwarding from local subnet" + ip_version: "ipv6" + state: "{{ 'present' if gateway_enabled else 'absent' }}" + +- name: "Add IPv6 FORWARD rule to accept established connections" + become: true + ansible.builtin.iptables: + chain: "FORWARD" + match: "conntrack" + ctstate: "RELATED,ESTABLISHED" + jump: "ACCEPT" + comment: "Allow IPv6 established connections" + ip_version: "ipv6" + state: "{{ 'present' if gateway_enabled else 'absent' }}" -- cgit v1.2.3