[Galene] Re: coturn config

[Juliusz Chroboczek <jch@irif.fr>]

> ...And it turns out that I completely misunderstood how this is supposed
> to work: there's not supposed to be any communication between the WebRTC
> server and Coturn. Rather, there's a configured shared secret that the
> WebRTC server can use to generate as many ephemeral credentials as it
> wants.

I just pushed an implementation.  Your ice-servers.json should look like
this:

    [
        {
            "urls": [
                "turn:turn.example.org:3479",
                "turn:turn.example.org:3479?transport=tcp"
            ],
            "username": "galene",
            "credential": "secret",
            "credentialType": "hmac-sha1"
        }
    ]

In other words, I've kept the standard configuration syntax, just added
a non-standard value for "credentialType".

Your turnserver.conf should look like this:

    use-auth-secret
    static-auth-secret=secret
    realm=trun.example.org

I've done some testing, but I didn't test that it will properly rotate the
key — please let me know if it survives 24h.

-- Juliusz