# Olm

Olm is a [WireGuard](https://www.wireguard.com/) tunnel client designed to securely connect you computer to Newt sites running on remote networks.

### Installation and Documentation

Olm is used with Pangolin and Newt as part of the larger system. See documentation below:

-   [Full Documentation](https://docs.fossorial.io)

## Key Functions

### Registers with Pangolin

Using the Olm ID and a secret, the olm will make HTTP requests to Pangolin to receive a session token. Using that token, it will connect to a websocket and maintain that connection. Control messages will be sent over the websocket.

### Receives WireGuard Control Messages

When Olm receives WireGuard control messages, it will use the information encoded (endpoint, public key) to bring up a WireGuard tunnel on your computer to a remote Newt. It will ping over the tunnel to ensure the peer is brought up.

## CLI Args

-   `endpoint`: The endpoint where both Gerbil and Pangolin reside in order to connect to the websocket.
-   `id`: Olm ID generated by Pangolin to identify the olm.
-   `secret`: A unique secret (not shared and kept private) used to authenticate the olm ID with the websocket in order to receive commands.
-   `mtu` (optional): MTU for the internal WG interface. Default: 1280
-   `dns` (optional): DNS server to use to resolve the endpoint. Default: 8.8.8.8
-   `log-level` (optional): The log level to use (DEBUG, INFO, WARN, ERROR, FATAL). Default: INFO
-   `ping-interval` (optional): Interval for pinging the server. Default: 3s
-   `ping-timeout` (optional): Timeout for each ping. Default: 5s
-   `interface` (optional): Name of the WireGuard interface. Default: olm
-   `enable-http` (optional): Enable HTTP server for receiving connection requests. Default: false
-   `http-addr` (optional): HTTP server address (e.g., ':9452'). Default: :9452
-   `holepunch` (optional): Enable hole punching. Default: false

## Environment Variables

All CLI arguments can also be set via environment variables:

-   `PANGOLIN_ENDPOINT`: Equivalent to `--endpoint`
-   `OLM_ID`: Equivalent to `--id`
-   `OLM_SECRET`: Equivalent to `--secret`
-   `MTU`: Equivalent to `--mtu`
-   `DNS`: Equivalent to `--dns`
-   `LOG_LEVEL`: Equivalent to `--log-level`
-   `INTERFACE`: Equivalent to `--interface`
-   `HTTP_ADDR`: Equivalent to `--http-addr`
-   `PING_INTERVAL`: Equivalent to `--ping-interval`
-   `PING_TIMEOUT`: Equivalent to `--ping-timeout`
-   `HOLEPUNCH`: Set to "true" to enable hole punching (equivalent to `--holepunch`)

Example:

```bash
olm \
--id 31frd0uzbjvp721 \
--secret h51mmlknrvrwv8s4r1i210azhumt6isgbpyavxodibx1k2d6 \
--endpoint https://example.com
```

## Hole Punching

In the default mode, olm "relays" traffic through Gerbil in the cloud to get down to newt. This is a little more reliable. Support for NAT hole punching is also EXPERIMENTAL right now using the `--holepunch` flag. This will attempt to orchestrate a NAT hole punch between the two sites so that traffic flows directly. This will save data costs and speed. If it fails it should fall back to relaying.

Right now, basic NAT hole punching is supported. We plan to add:

-   [ ] Birthday paradox
-   [ ] UPnP
-   [ ] LAN detection

## Windows Service

On Windows, olm has to be installed and run as a Windows service. When running it with the cli args live above it will attempt to install and run the service to function like a cli tool. You can also run the following:

### Service Management Commands

```
# Install the service
olm.exe install

# Start the service
olm.exe start

# Stop the service
olm.exe stop

# Check service status
olm.exe status

# Remove the service
olm.exe remove

# Run in debug mode (console output) with our without id & secret
olm.exe debug

# Show help
olm.exe help
```

### Service Configuration

When running as a service, Olm will read configuration from environment variables or you can modify the service to include command-line arguments:

1. Install the service: `olm.exe install`
2. Configure the service with your credentials using Windows Service Manager or by setting system environment variables:
    - `PANGOLIN_ENDPOINT=https://example.com`
    - `OLM_ID=your_olm_id`
    - `OLM_SECRET=your_secret`
3. Start the service: `olm.exe start`

### Service Logs

When running as a service, logs are written to:

-   Windows Event Log (Application log, source: "OlmWireguardService")
-   Log files in: `%PROGRAMDATA%\olm\logs\olm.log`

You can view the Windows Event Log using Event Viewer or PowerShell:

```powershell
Get-EventLog -LogName Application -Source "OlmWireguardService" -Newest 10
```

## Build

### Container

Ensure Docker is installed.

```bash
make
```

### Binary

Make sure to have Go 1.23.1 installed.

```bash
make local
```

## Licensing

Olm is dual licensed under the AGPLv3 and the Fossorial Commercial license. For inquiries about commercial licensing, please contact us.

## Contributions

Please see [CONTRIBUTIONS](./CONTRIBUTING.md) in the repository for guidelines and best practices.