Audio data sent when client has requested none

[matt335672]

xrdp version

All

Detailed xrdp version, build options

Argument 0 - xrdp
Argument 1 - -v
xrdp 0.10.80
  A Remote Desktop Protocol Server.
  Copyright (C) 2004-2024 Jay Sorg, Neutrino Labs, and all contributors.
  See https://github.com/neutrinolabs/xrdp for more information.

  Configure options:
      --enable-devel-all
      --enable-fuse
      --enable-pixman
      --enable-ipv6
      --enable-painter
      --enable-jpeg
      --with-imlib2
      --enable-vsock
      --with-freetype2
      --enable-utmp
      --with-libpcsclite
      --enable-neutrinordp
      --enable-ibus
      CC=gcc
      CFLAGS=-g -fvar-tracking -Wl,-z,now -Wno-error=deprecated-declarations

  Compiled with OpenSSL 3.0.2 15 Mar 2022

Operating system & version

Ubuntu 22.04

Installation method

Doesn't matter

Which backend do you use?

Either

What desktop environment do you use?

Any

Environment xrdp running on

VM

What's your client?

mstsc.exe

Area(s) with issue?

Audio redirection

Steps to reproduce

• Start a session with audio output disabled
• Load xrdp audio module
• Set breakpoint in chansrv process_pcm_message()
• Play audio

✔️ Expected Behavior

process_pcm_message() is not called

❌ Actual Behavior

process_pcm_message() is called, and sends data to client.

Anything else?

No response

[matt335672]

I've opened this following a conversation on Gitter with @derekschrock who has observed this.

We don't seem to be observing the INFO_NOAUDIOPLAYBACK flag in the TS_INFO_PACKET. This is probably quite fiddly to fix as we need to get the flag from xrdp to chansrv.

[matt335672]

To add to my comment above, the area which needs some attention is possibly xrdp_mm_trans_send_channel_setup() in xrdp_mm.c. The virtual channel rdpsnd is only used for audio output.