> ## Documentation Index
> Fetch the complete documentation index at: https://docs.allthingslinux.org/llms.txt
> Use this file to discover all available pages before exploring further.

# Finger (efingerd)

> Finger protocol via efingerd with socket activation and custom scripts.

[efingerd](https://packages.debian.org/trixie/efingerd) serves finger queries at `finger username@atl.sh` on port 79. It's socket-activated via systemd — no daemon runs until a connection arrives.

## How it works

```
finger client → systemd socket (:79) → efingerd
               → runs /etc/efingerd/luser script
               → reads ~/.plan and ~/.project
```

When a finger request arrives, systemd accepts the connection and spawns efingerd. efingerd runs one of its handler scripts depending on the query type:

| Script   | Triggered by                | Purpose                 |
| -------- | --------------------------- | ----------------------- |
| `luser`  | `finger username@atl.sh`    | Look up a specific user |
| `list`   | `finger @atl.sh`            | List logged-in users    |
| `nouser` | `finger nonexistent@atl.sh` | Handle unknown users    |
| `log`    | All queries                 | Logging                 |

The `luser` script reads `~/.plan` and `~/.project` to build the response. If the user has a `~/.efingerd` executable script, it runs that instead.

## User files

| File          | Purpose                                                 |
| ------------- | ------------------------------------------------------- |
| `~/.plan`     | Free-form text — what you're working on, thinking about |
| `~/.project`  | One-line project description                            |
| `~/.efingerd` | Optional custom script for full control over output     |

Both `.plan` and `.project` are created from `/etc/skel/` when the account is provisioned. Edit them with any text editor:

```bash theme={null}
nano ~/.plan
```

### Custom finger script

For full control, create an executable `~/.efingerd`:

```bash theme={null}
#!/bin/bash
echo "Login: $1"
echo "Last seen: $(last -1 $1 | head -1 | awk '{print $4, $5, $6, $7}')"
echo ""
cat ~/.plan
```

Make it executable: `chmod +x ~/.efingerd`

When present, efingerd runs this script instead of its default `luser` handler. `$1` is the queried username, `$2` is the requesting host.

## Ansible configuration

| File                                          | Purpose                                                                        |
| --------------------------------------------- | ------------------------------------------------------------------------------ |
| `roles/services/tasks/finger.yml`             | Install efingerd + finger client, set script permissions, deploy systemd units |
| `roles/services/templates/finger.socket.j2`   | Systemd socket unit (port 79)                                                  |
| `roles/services/templates/finger@.service.j2` | Systemd service template unit                                                  |

The `finger` client package is also installed — it's needed by efingerd's `luser` script to resolve user information.

All scripts in `/etc/efingerd/` are set to mode `0755` to ensure they're executable.

## Troubleshooting

**finger returns nothing or "no such user"**

* Verify the user exists: `getent passwd username`
* Check `~/.plan` exists and is readable: `ls -la ~/.plan`
* Test locally: `finger username@localhost`

**finger returns garbled output**

* Emoji or non-ASCII in `.plan` can cause issues with some clients
* The smoke test uses `grep -c` instead of direct output to avoid UTF-8 surrogate errors

**Socket not listening**

* Check: `systemctl status finger.socket`
* Restart: `sudo systemctl restart finger.socket`
* Verify port: `ss -tlnp | grep :79`