diff options
| -rw-r--r-- | docs/turn-howto.rst | 38 | ||||
| -rw-r--r-- | synapse/config/voip.py | 8 | ||||
| -rw-r--r-- | synapse/rest/client/v1/voip.py | 5 |
3 files changed, 46 insertions, 5 deletions
diff --git a/docs/turn-howto.rst b/docs/turn-howto.rst index 04c0100715..e48628ce6e 100644 --- a/docs/turn-howto.rst +++ b/docs/turn-howto.rst @@ -50,14 +50,37 @@ You may be able to setup coturn via your package manager, or set it up manually pwgen -s 64 1 - 5. Ensure youe firewall allows traffic into the TURN server on + 5. Consider your security settings. TURN lets users request a relay + which will connect to arbitrary IP addresses and ports. At the least + we recommend: + + # 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 + + 6. 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 if you've enabled both). + both TCP and UDP TURN traffic) - 6. If you've configured coturn to support TLS/DTLS, generate or + 7. If you've configured coturn to support TLS/DTLS, generate or import your private key and certificate. - 7. Start the turn server:: + 8. Start the turn server:: bin/turnserver -o @@ -83,12 +106,19 @@ Your home server configuration file needs the following extra keys: 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 Now, restart synapse:: diff --git a/synapse/config/voip.py b/synapse/config/voip.py index eeb693027b..3a4e16fa96 100644 --- a/synapse/config/voip.py +++ b/synapse/config/voip.py @@ -23,6 +23,7 @@ class VoipConfig(Config): self.turn_username = config.get("turn_username") self.turn_password = config.get("turn_password") self.turn_user_lifetime = self.parse_duration(config["turn_user_lifetime"]) + self.turn_allow_guests = config.get("turn_allow_guests", True) def default_config(self, **kwargs): return """\ @@ -41,4 +42,11 @@ class VoipConfig(Config): # How long generated TURN credentials last turn_user_lifetime: "1h" + + # Whether guests should be allowed to use the TURN server. + # This defaults to True, otherwise VoIP will be unreliable for guests. + # However, it does introduce a slight security risk as it allows users to + # connect to arbitrary endpoints without having first signed up for a + # valid account (e.g. by passing a CAPTCHA). + turn_allow_guests: True """ diff --git a/synapse/rest/client/v1/voip.py b/synapse/rest/client/v1/voip.py index 03141c623c..c43b30b73a 100644 --- a/synapse/rest/client/v1/voip.py +++ b/synapse/rest/client/v1/voip.py @@ -28,7 +28,10 @@ class VoipRestServlet(ClientV1RestServlet): @defer.inlineCallbacks def on_GET(self, request): - requester = yield self.auth.get_user_by_req(request) + requester = yield self.auth.get_user_by_req( + request, + self.hs.config.turn_allow_guests + ) turnUris = self.hs.config.turn_uris turnSecret = self.hs.config.turn_shared_secret |