169 lines
6.4 KiB
Markdown
169 lines
6.4 KiB
Markdown
# Overview
|
|
|
|
This document explains how to enable VoIP relaying on your homeserver with
|
|
TURN.
|
|
|
|
The synapse Matrix homeserver supports integration with TURN server via the
|
|
[TURN server REST API](<https://tools.ietf.org/html/draft-uberti-behave-turn-rest-00>). This
|
|
allows the homeserver to generate credentials that are valid for use on the
|
|
TURN server through the use of a secret shared between the homeserver and the
|
|
TURN server.
|
|
|
|
This documentation provides two TURN server configuration examples:
|
|
|
|
* [coturn](setup/turn/coturn.md)
|
|
* [eturnal](setup/turn/eturnal.md)
|
|
|
|
## Requirements
|
|
|
|
For TURN relaying to work, the TURN service must be hosted on a server/endpoint with a public IP.
|
|
|
|
Hosting TURN behind NAT requires port forwarding and for the NAT gateway to have a public IP.
|
|
However, even with appropriate configuration, NAT is known to cause issues and to often not work.
|
|
|
|
Afterwards, the homeserver needs some further configuration.
|
|
|
|
## Synapse setup
|
|
|
|
Your homeserver configuration file needs the following extra keys:
|
|
|
|
1. [`turn_uris`](usage/configuration/config_documentation.md#turn_uris)
|
|
2. [`turn_shared_secret`](usage/configuration/config_documentation.md#turn_shared_secret)
|
|
3. [`turn_user_lifetime`](usage/configuration/config_documentation.md#turn_user_lifetime)
|
|
4. [`turn_allow_guests`](usage/configuration/config_documentation.md#turn_allow_guests)
|
|
|
|
As an example, here is the relevant section of the config file for `matrix.org`. The
|
|
`turn_uris` are appropriate for TURN servers listening on the default ports, with no TLS.
|
|
|
|
turn_uris: [ "turn:turn.matrix.org?transport=udp", "turn:turn.matrix.org?transport=tcp" ]
|
|
turn_shared_secret: "n0t4ctuAllymatr1Xd0TorgSshar3d5ecret4obvIousreAsons"
|
|
turn_user_lifetime: 86400000
|
|
turn_allow_guests: true
|
|
|
|
After updating the homeserver configuration, you must restart synapse:
|
|
|
|
* If you use synctl:
|
|
```sh
|
|
# Depending on how Synapse is installed, synctl may already be on
|
|
# your PATH. If not, you may need to activate a virtual environment.
|
|
synctl restart
|
|
```
|
|
* If you use systemd:
|
|
```sh
|
|
systemctl restart matrix-synapse.service
|
|
```
|
|
... and then reload any clients (or wait an hour for them to refresh their
|
|
settings).
|
|
|
|
## Troubleshooting
|
|
|
|
The normal symptoms of a misconfigured TURN server are that calls between
|
|
devices on different networks ring, but get stuck at "call
|
|
connecting". Unfortunately, troubleshooting this can be tricky.
|
|
|
|
Here are a few things to try:
|
|
|
|
* Check that you have opened your firewall to allow TCP and UDP traffic to the
|
|
TURN ports (normally 3478 and 5349).
|
|
|
|
* Check that you have opened your firewall to allow UDP traffic to the UDP
|
|
relay ports (49152-65535 by default).
|
|
|
|
* Try disabling TLS/DTLS listeners and enable only its (unencrypted)
|
|
TCP/UDP listeners. (This will only leave signaling traffic unencrypted;
|
|
voice & video WebRTC traffic is always encrypted.)
|
|
|
|
* Some WebRTC implementations (notably, that of Google Chrome) appear to get
|
|
confused by TURN servers which are reachable over IPv6 (this appears to be
|
|
an unexpected side-effect of its handling of multiple IP addresses as
|
|
defined by
|
|
[`draft-ietf-rtcweb-ip-handling`](https://tools.ietf.org/html/draft-ietf-rtcweb-ip-handling-12)).
|
|
|
|
Try removing any AAAA records for your TURN server, so that it is only
|
|
reachable over IPv4.
|
|
|
|
* If your TURN server is behind NAT:
|
|
|
|
* double-check that your NAT gateway is correctly forwarding all TURN
|
|
ports (normally 3478 & 5349 for TCP & UDP TURN traffic, and 49152-65535 for the UDP
|
|
relay) to the NAT-internal address of your TURN server. If advertising
|
|
both IPv4 and IPv6 external addresses via the `external-ip` option, ensure
|
|
that the NAT is forwarding both IPv4 and IPv6 traffic to the IPv4 and IPv6
|
|
internal addresses of your TURN server. When in doubt, remove AAAA records
|
|
for your TURN server and specify only an IPv4 address as your `external-ip`.
|
|
|
|
* ensure that your TURN server uses the NAT gateway as its default route.
|
|
|
|
* Enable more verbose logging, in `coturn` via the `verbose` setting:
|
|
|
|
```
|
|
verbose
|
|
```
|
|
|
|
or with `eturnal` with the shell command `eturnalctl loglevel debug` or in the configuration file (the service needs to [reload](https://eturnal.net/documentation/#Operation) for it to become effective):
|
|
|
|
```yaml
|
|
## Logging configuration:
|
|
log_level: debug
|
|
```
|
|
|
|
... and then see if there are any clues in its logs.
|
|
|
|
* If you are using a browser-based client under Chrome, check
|
|
`chrome://webrtc-internals/` for insights into the internals of the
|
|
negotiation. On Firefox, check the "Connection Log" on `about:webrtc`.
|
|
|
|
(Understanding the output is beyond the scope of this document!)
|
|
|
|
* You can test your Matrix homeserver TURN setup with <https://test.voip.librepush.net/>.
|
|
Note that this test is not fully reliable yet, so don't be discouraged if
|
|
the test fails.
|
|
[Here](https://github.com/matrix-org/voip-tester) is the github repo of the
|
|
source of the tester, where you can file bug reports.
|
|
|
|
* There is a WebRTC test tool at
|
|
<https://webrtc.github.io/samples/src/content/peerconnection/trickle-ice/>. To
|
|
use it, you will need a username/password for your TURN server. You can
|
|
either:
|
|
|
|
* look for the `GET /_matrix/client/r0/voip/turnServer` request made by a
|
|
matrix client to your homeserver in your browser's network inspector. In
|
|
the response you should see `username` and `password`. Or:
|
|
|
|
* Use the following shell commands for `coturn`:
|
|
|
|
```sh
|
|
secret=staticAuthSecretHere
|
|
|
|
u=$((`date +%s` + 3600)):test
|
|
p=$(echo -n $u | openssl dgst -hmac $secret -sha1 -binary | base64)
|
|
echo -e "username: $u\npassword: $p"
|
|
```
|
|
|
|
or for `eturnal`
|
|
|
|
```sh
|
|
eturnalctl credentials
|
|
```
|
|
|
|
|
|
* Or (**coturn only**): Temporarily configure `coturn` to accept a static
|
|
username/password. To do this, comment out `use-auth-secret` and
|
|
`static-auth-secret` and add the following:
|
|
|
|
```
|
|
lt-cred-mech
|
|
user=username:password
|
|
```
|
|
|
|
**Note**: these settings will not take effect unless `use-auth-secret`
|
|
and `static-auth-secret` are disabled.
|
|
|
|
Restart coturn after changing the configuration file.
|
|
|
|
Remember to restore the original settings to go back to testing with
|
|
Matrix clients!
|
|
|
|
If the TURN server is working correctly, you should see at least one `relay`
|
|
entry in the results.
|