WG-API 🔐

WG-API presents a JSON-RPC interface on top of a WireGuard network interface.

• 💖 Add/Remove Peers Modify known peers without reloading

• 📈 Statistics View data usage and allowed IPs of all peers

• 📞 JSON-RPC 2.0 API No custom client integrations required, standard API accepted everywhere.

NOTE: WG-API is currently only compatible with the WireGuard Linux kernel module and userland wireguard-go. It does not currently work with the MacOS NetworkExtension.

Getting WG-API

Pre-Built Binary

Binaries for Linux are available here.

Build Yourself

WG-API requires at least Go 1.17.

go install github.com/jamescun/wg-api

This should install the server binary wg-api in your $GOPATH/bin.

Docker

WG-API can also be run inside a Docker container, however the container will need to existing within the same network namespace as the host and have network administrator capability (CAP_NET_ADMIN) to be able to control the WireGuard interface.

docker run --name=wg-api -d -p 8080:8080 --network host --cap-add NET_ADMIN james/wg-api:latest --device=<my device>

The Docker container now supports Linux on AMD64, ARM64 and ARMv7 architectures.

Configuring WG-API

WG is configured using command line arguments:

$ wg-api --help
WG-API presents a JSON-RPC API to a WireGuard device
Usage: wg-api [options]

Helpers:
  --list-devices  list wireguard devices on this system and their name to be
                  given to --device
  --version       display the version number of WG-API

Options:
  --device=<name>         (required) name of WireGuard device to manager
  --listen=<[host:]port>  address where API server will bind
                          (default localhost:8080)
  --tls                   enable Transport Layer Security (SSL) on server
  --tls-key               TLS private key
  --tks-cert              TLS certificate file
  --tls-client-ca         enable mutual TLS authentication (mTLS) of the client
  --token                 opaque value provided by the client to authenticate
                          requests. may be specified multiple times.

Environment Variables:
  WGAPI_TOKENS  comma seperated list of authentication tokens, equivalent to
                calling --token one or more times.

Warnings:
  WG-API can perform sensitive network operations, as such it should not be
  publicly exposed. It should be bound to the local interface only, or
  failing that, be behind an authenticating proxy or have mTLS enabled.
  Additionally authentication tokens should be configured.

The only required argument is --device, which tells WG-API which WireGuard device to control. To control multiple WireGuard devices, launch multiple instances of WG-API.

By default, this launches WG-API on localhost:8080 which may conflict with the typical development environment. To bind it elsewhere, use --listen:

$ wg-api --device=<my device> --listen=localhost:1234

NOTE: --listen will not prevent you from binding the server to a public interface. Care should be taken to prevent public access to the WG-API server; such as binding it only to a local interface, enabling auth tokens, placing an authenticating reverse proxy in-front of it or using mTLS (detailed below).

Authentication tokens can be provided either on the command line or via an environment variable. --token may be specified multiple times, or a comma-seperated list may be provided with the WGAPI_TOKENS environment variable. Environment variables are preferred as the token may be visible from process lists when using the command line --token.

$ WGAPI_TOKENS=<random string> wg-api --device=<my device>

Then provided as part of the HTTP exchange in the HTTP Authorization header as the Token scheme.

$ curl http://localhost:8080 -H "Authorization: Token <random string>" ...

POST / HTTP/1.1
Host: localhost:8080
Authorization: Token <random string>
Content-Type: application/json

WG-API can optional listen using TLS and HTTP/2. To enable TLS, you will also need a TLS Certificate and matching private key.

$ wg-api --device=<my device> --tls --tls-key=key.pem --tls-cert=cert.pem

And optionally WG-API can request and validate client certificates to implement TLS Mutual Authentication (mTLS):

$ wg-api --device=<my device> --tls --tls-key=key.pem --tls-cert=cert.pem --tls-client-ca=clientca.pem

Using WG-API

WG-API exposes a JSON-RPC 2.0 API with five methods.

All calls are made using the POST method, and require the Content-Type header to be set to application/json. The server ignores the URL path it is given, allowing the server to be mounted under another hierarchy in a reverse proxy.

The structures expected by the server can be found in client/client.go.

Authentication may optionally be configured. This is supplied via the Authorization header as the Token scheme. See Configuring WG-API for an example.

GetDeviceInfo

GetDeviceInfo returns information such as the public key and type of interface for the currently configured device.

curl http://localhost:8080 -H "Content-Type: application/json" -d '{"jsonrpc": "2.0", "method": "GetDeviceInfo", "params": {}}'

Example Response

{
  "device": {
    "name": "wg0",
    "type": "Linux kernel",
    "public_key": "xoY2MZZ1UmbEakFBPyqryHwTaMi6ae4myP+vuILmJUY=",
    "listen_port": 51820,
    "num_peers": 13
  }
}

ListPeers

ListPeers retrieves information about all Peers known to the current WireGuard interface, including allowed IP addresses and usage stats, optionally with pagination.

curl http://localhost:8080 -H "Content-Type: application/json" -d '{"jsonrpc": "2.0", "method": "ListPeers", "params": {}}'

Example Response

{
  "peers": [
    {
      "public_key": "xoY2MZZ1UmbEakFBPyqryHwTaMi6ae4myP+vuILmJUY=",
      "has_preshared_key": false,
      "endpoint": "67.234.65.104:57436",
      "last_handshake": "2020-02-20T16:35:12Z",
      "receive_bytes": 834854756,
      "transmit_bytes": 3883746,
      "allowed_ips": [
        "10.1.1.0/24"
      ],
      "protocol_version": 1
    },
    ...
  ]
}

GetPeer

GetPeer retrieves a specific Peer by their public key.

curl http://localhost:8080 -H "Content-Type: application/json" -d '{"jsonrpc": "2.0", "method": "GetPeer", "params": {"public_key": "xoY2MZZ1UmbEakFBPyqryHwTaMi6ae4myP+vuILmJUY="}}'

Example Response

{
  "peer": {
    "public_key": "xoY2MZZ1UmbEakFBPyqryHwTaMi6ae4myP+vuILmJUY=",
    "has_preshared_key": false,
    "endpoint": "67.234.65.104:57436",
    "last_handshake": "2020-02-20T16:35:12Z",
    "receive_bytes": 834854756,
    "transmit_bytes": 3883746,
    "allowed_ips": [
      "10.1.1.0/24"
    ],
    "protocol_version": 1
  }
}

AddPeer

AddPeer inserts a new Peer into the WireGuard interfaces table, multiple calls to AddPeer can be used to update details of the Peer.

curl http://localhost:8080 -H "Content-Type: application/json" -d '{"jsonrpc": "2.0", "method": "AddPeer", "params": {"public_key": "xoY2MZZ1UmbEakFBPyqryHwTaMi6ae4myP+vuILmJUY=","allowed_ips": [ "10.1.1.0/24" ]}}'

RemovePeer

RemovePeer deletes a Peer from the WireGuard interfaces table by their public key,

curl http://localhost:8080 -H "Content-Type: application/json" -d '{"jsonrpc": "2.0", "method": "RemovePeer", "params": {"public_key": "xoY2MZZ1UmbEakFBPyqryHwTaMi6ae4myP+vuILmJUY="}}'

Thanks

With many thanks to:

• Jason A. Donenfeld