mirror of
https://github.com/element-hq/synapse.git
synced 2024-11-23 01:55:53 +03:00
124 lines
4.8 KiB
Markdown
124 lines
4.8 KiB
Markdown
|
# Overview
|
||
|
|
||
|
This document explains how to enable VoIP relaying on your Home Server with
|
||
|
TURN.
|
||
|
|
||
|
The synapse Matrix Home Server supports integration with TURN server via the
|
||
|
[TURN server REST API](<http://tools.ietf.org/html/draft-uberti-behave-turn-rest-00>). This
|
||
|
allows the Home Server to generate credentials that are valid for use on the
|
||
|
TURN server through the use of a secret shared between the Home Server and the
|
||
|
TURN server.
|
||
|
|
||
|
The following sections describe how to install [coturn](<https://github.com/coturn/coturn>) (which implements the TURN REST API) and integrate it with synapse.
|
||
|
|
||
|
## `coturn` Setup
|
||
|
|
||
|
### Initial installation
|
||
|
|
||
|
The TURN daemon `coturn` is available from a variety of sources such as native package managers, or installation from source.
|
||
|
|
||
|
#### Debian installation
|
||
|
|
||
|
# apt install coturn
|
||
|
|
||
|
#### Source installation
|
||
|
|
||
|
1. Download the [latest release](https://github.com/coturn/coturn/releases/latest) from github. Unpack it and `cd` into the directory.
|
||
|
|
||
|
1. Configure it:
|
||
|
|
||
|
./configure
|
||
|
|
||
|
> You may need to install `libevent2`: if so, you should do so in
|
||
|
> the way recommended by your operating system. You can ignore
|
||
|
> warnings about lack of database support: a database is unnecessary
|
||
|
> for this purpose.
|
||
|
|
||
|
1. Build and install it:
|
||
|
|
||
|
make
|
||
|
make install
|
||
|
|
||
|
1. Create or edit the config file in `/etc/turnserver.conf`. The relevant
|
||
|
lines, with example values, are:
|
||
|
|
||
|
use-auth-secret
|
||
|
static-auth-secret=[your secret key here]
|
||
|
realm=turn.myserver.org
|
||
|
|
||
|
See `turnserver.conf` for explanations of the options. One way to generate
|
||
|
the `static-auth-secret` is with `pwgen`:
|
||
|
|
||
|
pwgen -s 64 1
|
||
|
|
||
|
1. Consider your security settings. TURN lets users request a relay which will
|
||
|
connect to arbitrary IP addresses and ports. The following configuration is
|
||
|
suggested as a minimum starting point:
|
||
|
|
||
|
# VoIP traffic is all UDP. There is no reason to let users connect to arbitrary TCP endpoints via the relay.
|
||
|
no-tcp-relay
|
||
|
|
||
|
# don't let the relay ever try to connect to private IP address ranges within your network (if any)
|
||
|
# given the turn server is likely behind your firewall, remember to include any privileged public IPs too.
|
||
|
denied-peer-ip=10.0.0.0-10.255.255.255
|
||
|
denied-peer-ip=192.168.0.0-192.168.255.255
|
||
|
denied-peer-ip=172.16.0.0-172.31.255.255
|
||
|
|
||
|
# special case the turn server itself so that client->TURN->TURN->client flows work
|
||
|
allowed-peer-ip=10.0.0.1
|
||
|
|
||
|
# consider whether you want to limit the quota of relayed streams per user (or total) to avoid risk of DoS.
|
||
|
user-quota=12 # 4 streams per video call, so 12 streams = 3 simultaneous relayed calls per user.
|
||
|
total-quota=1200
|
||
|
|
||
|
Ideally coturn should refuse to relay traffic which isn't SRTP; see
|
||
|
<https://github.com/matrix-org/synapse/issues/2009>
|
||
|
|
||
|
1. Ensure your firewall allows traffic into the TURN server on the ports
|
||
|
you've configured it to listen on (remember to allow both TCP and UDP TURN
|
||
|
traffic)
|
||
|
|
||
|
1. If you've configured coturn to support TLS/DTLS, generate or import your
|
||
|
private key and certificate.
|
||
|
|
||
|
1. Start the turn server:
|
||
|
|
||
|
bin/turnserver -o
|
||
|
|
||
|
## synapse Setup
|
||
|
|
||
|
Your home server configuration file needs the following extra keys:
|
||
|
|
||
|
1. "`turn_uris`": This needs to be a yaml list of public-facing URIs
|
||
|
for your TURN server to be given out to your clients. Add separate
|
||
|
entries for each transport your TURN server supports.
|
||
|
2. "`turn_shared_secret`": This is the secret shared between your
|
||
|
Home server and your TURN server, so you should set it to the same
|
||
|
string you used in turnserver.conf.
|
||
|
3. "`turn_user_lifetime`": This is the amount of time credentials
|
||
|
generated by your Home Server are valid for (in milliseconds).
|
||
|
Shorter times offer less potential for abuse at the expense of
|
||
|
increased traffic between web clients and your home server to
|
||
|
refresh credentials. The TURN REST API specification recommends
|
||
|
one day (86400000).
|
||
|
4. "`turn_allow_guests`": Whether to allow guest users to use the
|
||
|
TURN server. This is enabled by default, as otherwise VoIP will
|
||
|
not work reliably for guests. However, it does introduce a
|
||
|
security risk as it lets guests connect to arbitrary endpoints
|
||
|
without having gone through a CAPTCHA or similar to register a
|
||
|
real account.
|
||
|
|
||
|
As an example, here is the relevant section of the config file for matrix.org:
|
||
|
|
||
|
turn_uris: [ "turn:turn.matrix.org:3478?transport=udp", "turn:turn.matrix.org:3478?transport=tcp" ]
|
||
|
turn_shared_secret: n0t4ctuAllymatr1Xd0TorgSshar3d5ecret4obvIousreAsons
|
||
|
turn_user_lifetime: 86400000
|
||
|
turn_allow_guests: True
|
||
|
|
||
|
After updating the homeserver configuration, you must restart synapse:
|
||
|
|
||
|
cd /where/you/run/synapse
|
||
|
./synctl restart
|
||
|
|
||
|
..and your Home Server now supports VoIP relaying!
|