[pulseaudio-discuss] Connect to non system-wide pulse server inside root privilege program (Asynchronous API)

[Arun Raghavan]

On Tue, 5 Nov 2019, at 3:50 PM, Andrey wrote:
> Hi all!
> 
> Pf: Issue with pa_context_connect() call inside root privilege program.
> 
> I have Xubuntu 19.10. On default pulseaudio server (ver 13.0) started on 
> user logon with "--demonize=no" parameter. I need reroute digital sound 
> from /dev/dsp  to pulse. For this i install osspd  package (current ver 
> 1.3.2-11). I have successfully used this package previously on Ubuntu 
> 16.04/18.04-3 with no any tuning. Osspd daemon get source trough CUSE 
> and required root privileges. I.e. osspd call pulse as root. I copy 
> user's cookie file to /root/.config/pulse/cookie. But osspd can't 
> connect to pulse server again. My distribution belongs to group 2 and i 
> no put users to the "audio" group (but i test opposed: nothing happens :) ).
> 
> I debug osspd's slave processes (ossp-padsp) and detect what function 
> pa_context_connect() return code 'connection refused'. I tried to run 
> ossp-padsp as user - it connected to server successful. Then i call 
> pa_context_connect() with name of server 
> "unix:/run/user/1000/pulse/native" (instead NULL).... the connection is 
> established! And as ordinary user and as root! It works for me now.
> 
> BUT... I assume that somewhere something with settings of access rights 
> to the pulse server I missed... What and where? How correctly should I 
> connect to the non system-wide pulse server as root?
> 
> Is this behavior of the connection process a normal(documented?) or bug? 
> Can i (is it right) use this feature to select the specific user's pulse 
> server to connect?

Not sure what the issue you have is, but there is one big hammer to sidestep this problem -- you can provide auth_anonymous=1 to module-native-protocol-unix in default.pa, and any local client can then connect.

-- Arun