#+TITLE: Chrooting zoom on linux
#+SHORT-TITLE: zoom
#+TOC-KEYWORDS: linux
#+KEYWORDS: linux, chroot
#+DESCRIPTION: chrooted zoom in Debian

#+BEGIN(menu):left
[[toc][]]
#+END

* Introduction
Back in 2000s, Skype was a good program with linux support until Microsoft bought it.
At that time Microsoft was aggressively trying to defend its monopoly
by killing linux, so eventually Skype stopped supporting linux.

Since the pandemic many people use [[https://zoom.us/][zoom]] so it makes sense to install it on my linux laptop.
However, I do not trust [[https://zoom.us/][zoom]] and its creators;
I suspect that it may work as a spyware with numerous vulnerabilities allowing
unauthorized access to my data.

[[https://www.youtube.com/watch?v=kJOvr96Wwko][They say]], [[https://jami.net/][jami]] is an alternative to skype and [[https://zoom.us/][zoom]] but
even if [[https://jami.net/][jami]] is better, still everyone has to use whatever schools and corporations choose.

Below I share my experience on installing [[https://zoom.us/][zoom]] on Debian.
(Note that [[https://www.microsoft.com/en-us/microsoft-teams/group-chat-software][MS teams]] refused to start after I tried to install it using the same approach.)

*:max-width=65ex Creating the sandbox
The purpose of the sandbox is to prevent unauthorized access to my files.

All my sandboxes are stored in [[src:\/mnt\/sandbox\/]]:

#+BEGIN(src):root shell
mkdir -p /mnt/sandbox/zoom
#+END

Installing [[https://www.debian.org/releases/buster/][Debian Buster]] (somewhat obsolete, but working):
#+BEGIN(src):root shell
chgrp -R tmp /mnt/sandbox
chmod a+rx /mnt /mnt/sandbox
debootstrap buster /mnt/sandbox/zoom
mkdir /mnt/sandbox/zoom/home/shalaev
chown shalaev.shalaev /mnt/sandbox/zoom/home/shalaev
#+END
where in my linux configuration the group [[src:tmp]] prevents backups, and
[[src:shalaev]] is my user- and group name.

* Configuring schroot
Here is my zoom configuration:
#+BEGIN(src):/etc/schroot/schroot.conf
[zoom]
description=debian created under chroot
type=directory
directory=/mnt/sandbox/zoom
profile=buster
users=shalaev
groups=shalaev
root-groups=root
#+END

#+BEGIN(src):/etc/schroot/buster/copyfiles
/etc/resolv.conf
#+END

#+BEGIN(src):/etc/schroot/buster/fstab
/proc    /proc    none rw,bind 0 0
/sys     /sys     none rw,bind 0 0
/dev     /dev     none rw,bind 0 0
/dev/pts /dev/pts none rw,bind 0 0
/run     /run     none rw,bind 0 0
#+END

#+BEGIN(src):/etc/schroot/buster/nssdatabases
passwd
shadow
group
gshadow
services
protocols
networks
hosts
#+END

*:max-width=100ex Installing zoom inside chroot
Assuming that we have already downloaded [[https://zoom.us/][zoom]] into [[src:\~/Downloads/]]:
#+BEGIN(src):root shell
mkdir -p /mnt/sandbox/zoom/{srv/local-apt-repository,var/lib/local-apt-repository}
mv ~shalaev/Downloads/zoom_amd64.deb /mnt/sandbox/zoom/srv/local-apt-repository/
schroot -c zoom -u root --directory /
#+END
Then, inside an schroot shell,
we install [[https://packages.debian.org/buster/local-apt-repository][local-apt-repository]] which will allow us to treat [[https://zoom.us/][zoom]]
as if it was part of the Debian repository:
#+BEGIN(src):chroot root shell
apt-get install aptitude local-apt-repository
/usr/lib/local-apt-repository/rebuild
#+END
Now we can install [[https://zoom.us/][zoom]] using [[src:aptitude]] or [[src:apt-get]] or any other package manager:
#+BEGIN(src):chroot root shell
aptitude update
aptitude install zoom
#+END
The last command will install all the necessary dependencies.

Note that [[https://zoom.us/][zoom]] requires [[https://wiki.archlinux.org/title/PulseAudio][pulse audio]].
(I am  annoyed by that because I do not need more functionality than [[https://wiki.archlinux.org/title/ALSA][ALSA]] provides,
and [[https://wiki.archlinux.org/title/PulseAudio][pulse audio]] is less stable than  [[https://wiki.archlinux.org/title/ALSA][ALSA]].)

* Starting the zoom session
(Note that we do not need root privileges any more.)
#+BEGIN(src):shell
schroot -c zoom -d ~
#+END
#+BEGIN(src):chroot shell
export DISPLAY=:0
zoom
#+END
Do not forget to quit [[https://zoom.us/][zoom]] as well as the chroot session when you are done with it.