prosody/readme.md

# Prosody XMPP server for Raspberry Pi

This docker image provides you with a configured [Prosody](https://prosody.im/) XMPP server. The image is intended to run on a Raspberry Pi (as it is based on _balenalib/rpi-raspbian_).
The server was tested using the Android App [Conversations](https://conversations.im/) and the Desktop client [Gajim](https://gajim.org).

While Conversations got everything set-up out-of-the-box, Gajim was used with the following extensions:

* HttpUpload
* Off-The-Record Encryption
* OMEMO (requires _python-axolotl_ to be installed)
* Url Image preview

## Table of Contents

- [Prosody XMPP server for Raspberry Pi](#prosody-xmpp-server-for-raspberry-pi)
  - [Table of Contents](#table-of-contents)
  - [Features](#features)
  - [Requirements](#requirements)
  - [Image Details](#image-details)
    - [Ports](#ports)
    - [Directories](#directories)
      - [Data](#data)
      - [Bundled modules](#bundled-modules)
      - [Additionally installed prosody modules](#additionally-installed-prosody-modules)
      - [Config](#config)
      - [SSL certificates](#ssl-certificates)
        - [Folder structure](#folder-structure)
        - [Symlinks](#symlinks)
        - [Permissions](#permissions)
    - [Run](#run)
    - [Configuration](#configuration)
      - [Environment variables](#environment-variables)
      - [DNS](#dns)
      - [server_contact_info](#server_contact_info)
    - [Extend](#extend)
    - [Upgrade](#upgrade)
  - [Test your server](#test-your-server)

## Features

* Secure by default
  * SSL certificate required
  * End-to-end encryption required (using [OMEMO](https://conversations.im/omemo/) or [OTR](https://en.wikipedia.org/wiki/Off-the-Record_Messaging))
* Data storage
  * SQLite message store
  * Configured file upload and image sharing
* Allows registration
* Multi-user chats

## Requirements

* You need a SSL certificate. I recommend [LetsEncrypt](https://letsencrypt.org/) for that.
* Your Raspberry Pi should have docker set-up and running. You could use the Raspberry image for [Hypriot OS](http://blog.hypriot.com/downloads/) to get started quickly.

## Image Details

### Ports

The following ports are exposed:

* 5000: proxy65 port used for file sharing
* 5222: c2s port (client to server)
* 5223: c2s legacy ssl port (client to server)
* 5269: s2s port (server to server)
* 5347: XMPP component port
* 5280: BOSH / websocket port
* 5281: Secure BOSH / websocket port

### Directories

#### Data

Path: ```/usr/local/var/lib/prosody/```.

* used for SQLite file
* used for HTTP uploads
* this is exposed as docker volume
  
#### Bundled modules

Path: ```/usr/local/lib/prosody/modules/```.

#### Additionally installed prosody modules

Path: ```/usr/local/lib/prosody/custom-modules/```.

#### Config

Path: ```/usr/local/etc/prosody/```.

* containing the main config file called ```prosody.cfg.lua```
* containing additional config files within ```conf.d/```

#### SSL certificates

Path: ```/usr/local/etc/prosody/certs/```.

Uses [automatic location](https://prosody.im/doc/certificates#automatic_location) to find your certs.

The http_upload module does not use the same search algorithm for the certificates. See [service certificates](https://prosody.im/doc/certificates#service_certificates).

The setting ssl in [05-vhost.cfg.lua](./conf.d/05-vhost.cfg.lua) configures certificates globally as a fallback.

Which defaults to ```cert/domain.tld/fullchain.pem``` and ```cert/domain.tld/privkey.pem```.

##### Folder structure

An example certificate folder structure could look like this:

``` zsh
certs
├── conference.domain.tld
│   ├── fullchain.pem
│   └── privkey.pem
├── proxy.domain.tld
│   ├── fullchain.pem
│   └── privkey.pem
├── upload.domain.tld
│   ├── fullchain.pem
│   └── privkey.pem
└── domain.tld
    ├── fullchain.pem
    └── privkey.pem
```

Thats how Let's encrypt certbot does it out of the box.

##### Symlinks

certbot creates the structure and uses symlinks to the actual certificates.
If you mount them like that prosody somehow does not find them.
I copied them to a folder named ```certs``` next to my ```docker-compose.yml``` and made sure to use the ```-L``` flag of ```cp```.
This makes cp follow symbolic links when copying from them.
For example ```cp -L src dest```.

##### Permissions

TODO

### Run

I recommend using a ```docker-compose.yml``` file:

```yaml
version: '2'

services:
  server:
    image: shaula/rpi-prosody:0.10
    ports:
      - "5000:5000"
      - "5222:5222"
      - "5223:5223"
      - "5269:5269"
      - "5281:5281"
    environment:
      DOMAIN: domain.tld
    volumes:
      - ./certs:/usr/local/etc/prosody/certs
      - ./data:/usr/local/var/lib/prosody
    restart: unless-stopped
```

Boot it via: ```docker-compose up -d```.

Inspect logs: ```docker-compose logs -f```.

### Configuration

#### Environment variables

| Variable                   | Description                                                                                             | Type         | Default value         |
| -------------------------- | ------------------------------------------------------------------------------------------------------- | ------------ | --------------------- |
| **ALLOW_REGISTRATION**     | Whether to allow registration of new accounts via Jabber clients                                        | *optional*   | true                  |
| **DOMAIN**                 | domain                                                                                                  | **required** | null                  |
| **DOMAIN_HTTP_UPLOAD**     | Domain which lets clients upload files over HTTP                                                        | *optional*   | upload.**DOMAIN**     |
| **DOMAIN_MUC**             | Domain for Multi-user chat (MUC) for allowing you to create hosted chatrooms/conferences for XMPP users | *optional*   | conference.**DOMAIN** |
| **DOMAIN_PROXY**           | Domain for SOCKS5 bytestream proxy for server-proxied file transfers                                    | *optional*   | proxy.**DOMAIN**      |
| **DOMAIN_PUBSUB**          | Domain for a XEP-0060 pubsub service                                                                    | *optional*   | pubsub.**DOMAIN**     |
| **LOG_LEVEL**              | Min log level. Change to debug for more information                                                     | *optional*   | info                  |
| **C2S_REQUIRE_ENCRYPTION** | Whether to force all client-to-server connections to be encrypted or not                                | *optional*   | true                  |
| **S2S_REQUIRE_ENCRYPTION** | Whether to force all server-to-server connections to be encrypted or not                                | *optional*   | true                  |
| **S2S_SECURE_AUTH**        | Require encryption and certificate authentication                                                       | *optional*   | true                  |

#### DNS

You need these DNS record pointing to your server:

* domain.tld
* conference.domain.tld
* proxy.domain.tld
* pubsub.domain.tld
* upload.domain.tld
* A SRV record for _xmpps-client._tcp.domain.tld for port 5223.

where domain.tld is the environment variable DOMAIN.

#### server_contact_info

This module lets you advertise various contact addresses for your XMPP service via XEP-0157.
It is configured for the following contacts:

* abuse
* admin
* feedback
* sales
* security
* support

You can change them in [05-server_contact_info.cfg.lua](./conf.d/04-server_contact_info.cfg.lua).

### Extend

There is a helper script that eases installing additional prosody modules: ```docker-prosody-module-install```

It downloads the current [prosody-modules](https://hg.prosody.im/prosody-modules/) repository. The specified modules are copied and its name is added to the ```modules_enabled``` variable within ```conf.d/01-modules.cfg.lua```.

There is also ```docker-prosody-module-copy``` which copies the specified modules but does not add them to the ```modules_enabled``` variable within ```conf.d/01-modules.cfg.lua```.

If you need additional configuration just overwrite the respective _cfg.lua_ file or add new ones.

### Upgrade

When migrating from 0.10, you need to update the database once:

```bash
docker-compose exec server bash
prosodyctl mod_storage_sql upgrade
```

## Test your server

You can test your server with these websites:

* [IM Observatory](https://www.xmpp.net/)
* [XMPP Compliance Tester](https://compliance.conversations.im/)