Install Kicksecure inside a folder (chroot)

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You can install Kicksecure on top of your existing Debian (based) Linux installation inside a chroot.

Introduction[edit]

Understanding the Basics of Creating and Using a Chroot Environment

Creating and using a chroot is like building a small, isolated Linux system within your main system. It's a powerful tool for various purposes, from development to testing. While the concept might seem overwhelming at first, it boils down to a few key commands and a basic understanding of Linux file systems.

In the world of Linux, mastering the creation and use of a chroot (change root) environment is a valuable skill. This process involves two fundamental steps: creating the chroot and then operating within it.

Before we can discuss the chroot (change root), we first need to define what the root directory is. In Linux, the root directory path symbolized only by a single / (forward slash). See also ls / . It contains other directories you might already know such as /etc, /usr, /lib, /var, and so forth.

Creating the Chroot Environment

The chroot environment is essentially a miniature version of a Linux system within your existing system.

To create this environment, you can use tools like debootstrap or mmdebstrap. These tools download a Linux distribution (like Debian or others from different repositories such as Kicksecure) and establish a root file system in a designated folder on your hard drive. For instance, you might create a chroot folder named ~/kicksecure-xfce-chroot. That folder would then contain same essential directories, /etc, /usr, and so forth. Here's an example how that folder structure would look like.

  • ~/kicksecure-xfce-chroot/etc
  • ~/kicksecure-xfce-chroot/usr
  • ~/kicksecure-xfce-chroot/lib
  • etc.

This folder structe gets created by the chroot creation tool. There's no need for the user to fully understand the folder structure or process. The process is straightforward, typically requiring just a single command line instruction.

Using the Chroot Environment

Once the chroot folder has been set up, you can start working inside it using commands like chroot or systemd-nspawn.

An example of entering this environment would be: sudo chroot ~/kicksecure-xfce-chroot zsh. This command changes the root from the main / to ~/kicksecure-xfce-chroot and starts the Z shell (zsh) in this new context. But don't worry. This does not change the root for your real Linux installation. It only changes the root for the terminal emulator which you are currently using. The rest of your system remains unaffected by this.

You could also use other shells such as bash or applications as needed.

It’s worth noting that more advanced setups might involve emulators like QEMU for a fully emulated operating system, but this would require additional steps like installing a kernel in the chroot.

chroot Creation[edit]

notice This is a pre-release. (What does that mean?)

Qubes Notes[edit]

Only users of Qubes need to consider these notes in this chapter.

Users that don't use Qubes or don't know what Qubes is should skip this chapter.

TODO: elaborate

  • nosuid / nodev can cause issues?
  • default private image size (/home folder) is too small for Kicksecure Xfce

Install Required Tools[edit]

[1]

Install mmdebstrap apt-transport-https apt-transport-tor tor curl. To accomplish that, the following steps A. to D. need to be done.

A. Update the package lists.

sudo apt update

B. Upgrade the system.

sudo apt full-upgrade

C. Install the mmdebstrap apt-transport-https apt-transport-tor tor curl package.

Using apt command line parameter --no-install-recommends is in most cases optional.

sudo apt install --no-install-recommends mmdebstrap apt-transport-https apt-transport-tor tor curl

D. Done.

The procedure of installing mmdebstrap apt-transport-https apt-transport-tor tor curl is complete.

Add Signing Key[edit]

It is required to add the signing key on the host because mmdebstrap will need it.

(Users of Kicksecure and Kicksecure could skip this step since the signing key is there by default.)

Key could be removed at the end. (Except Kicksecure and Kicksecure should not do this unless they upgrade from source code.)

Complete the following steps to add the Kicksecure Signing Key to the system's APT keyring.

Open a terminal.

1. Package curl needs to be installed.

Install curl. To accomplish that, the following steps A. to D. need to be done.

A. Update the package lists.

sudo apt update

B. Upgrade the system.

sudo apt full-upgrade

C. Install the curl package.

Using apt command line parameter --no-install-recommends is in most cases optional.

sudo apt install --no-install-recommends curl

D. Done.

The procedure of installing curl is complete.

2. Download Kicksecure Signing Key. [2]

A : Debian

If you are using Debian, run.

TLS

sudo curl --tlsv1.3 --output /usr/share/keyrings/derivative.asc --url https://www.kicksecure.com/keys/derivative.asc

onion

Downloading over onion requires an already functional system Tor.

sudo torsocks curl --output /usr/share/keyrings/derivative.asc --url http://www.w5j6stm77zs6652pgsij4awcjeel3eco7kvipheu6mtr623eyyehj4yd.onion/keys/derivative.asc

B : Qubes

If you are using a Qubes Debian Template, run.

TLS

sudo http_proxy=http://127.0.0.1:8082 https_proxy=http://127.0.0.1:8082 curl --tlsv1.3 --output /usr/share/keyrings/derivative.asc --url https://www.kicksecure.com/keys/derivative.asc

onion

Downloading over onion requires an already functional system Tor.

sudo torsocks curl --output /usr/share/keyrings/derivative.asc --url http://www.w5j6stm77zs6652pgsij4awcjeel3eco7kvipheu6mtr623eyyehj4yd.onion/keys/derivative.asc

3. Users can check Kicksecure Signing Key for better security.

4. Done.

The procedure of adding the Kicksecure signing key is now complete.

Set Variables[edit]

File /etc/hostname must exist. [3]

sudo touch /etc/hostname

Set Variables[edit]

Note: You could also replace kicksecure-xfce with kicksecure-cli.

package=kicksecure-xfce repo=bookworm path_to_chroot=~/kicksecure-xfce-chroot path_to_temp_sources_list=~/temp-sources.list

APT Sources List[edit]

Create temporary APT sources list for mmdebstrap.

echo " deb https://deb.debian.org/debian-security bookworm-security main contrib non-free deb https://deb.debian.org/debian bookworm main contrib non-free deb [signed-by=/usr/share/keyrings/derivative.asc] https://deb.kicksecure.com $repo main contrib non-free " > "$path_to_temp_sources_list"

APT Cache[edit]

Optional. If you are interested, please press Expand on the right side.

This shouldn't be done unless you are behind a firewall since apt-cacher-ng will by default listen on all network interfaces.

Install apt-cacher-ng. To accomplish that, the following steps A. to D. need to be done.

A. Update the package lists.

sudo apt update

B. Upgrade the system.

sudo apt full-upgrade

C. Install the apt-cacher-ng package.

Using apt command line parameter --no-install-recommends is in most cases optional.

sudo apt install --no-install-recommends apt-cacher-ng

D. Done.

The procedure of installing apt-cacher-ng is complete.

Set apt_cacher_ng_maybe variable. [4]

http_proxy=http://127.0.0.1:3142

Create apt-cacher-ng https compatible sources.list file.

echo " deb http://HTTPS///deb.debian.org/debian-security/ bookworm-security main contrib non-free deb http://HTTPS///deb.debian.org/debian bookworm main contrib non-free deb [signed-by=/usr/share/keyrings/derivative.asc] http://HTTPS///deb.kicksecure.com $repo main contrib non-free " > "$path_to_temp_sources_list"

Run mmdebstrap[edit]

Run mmdebstrap. [5]

sudo \ $apt_cacher_ng_maybe \ SECURITY_MISC_INSTALL=force \ DERIVATIVE_APT_REPOSITORY_OPTS=stable \ mmdebstrap \ --verbose \ --variant=required \ --include $package \ $repo \ "$path_to_chroot" \ "$path_to_temp_sources_list"

Chroot Post Processing[edit]

Delete the chroot's temporary /etc/apt/sources.list. [6]

sudo rm "$path_to_chroot/etc/apt/sources.list"

sudo rm "$path_to_chroot/etc/apt/sources.list.d/0000temp-sources.list"

Host Cleanup[edit]

Optional. You can delete the signing key from the host.

If you are interested, please press Expand on the right side.

This is only useful for users not using Kicksecure as their host operating system.

Users of Kicksecure must skip this.

sudo rm /etc/apt/trusted.gpg.d/derivative.gpg

Usage[edit]

Simple Classic Chroot Method[edit]

sudo chroot ~/kicksecure-xfce-chroot zsh

systemd-nspawn Method[edit]

Install systemd-nspawn[edit]

sudo apt install systemd-container

systemd-nspawn Simple Chroot[edit]

sudo systemd-nspawn -D ~/kicksecure-xfce-chroot

systemd-nspawn Boot Chroot CLI Only[edit]

sudo systemd-nspawn -D ~/kicksecure-xfce-chroot /sbin/init

Troubleshooting[edit]

sudo[edit]

sudo su

If seeing this error when using "sudo su". 

sudo: effective uid is not 0, is /usr/bin/sudo on a file system with the 'nosuid' option set or an NFS file system without root privileges?
  • Qubes users:
    • If using mounting home with nosuid.

sudo mount -o remount,suid /rw/home

networking[edit]

systemd-networkd must be enabled on both, the host and inside the VM.

sudo systemctl enable systemd-networkd

sudo systemctl start systemd-networkd

systemd-nspawn Boot Chroot with GUI Support[edit]

This is unfinished. Unspecific to Kicksecure. Could be resolved as per Self Support First Policy.

xhost +local:

sudo systemd-nspawn --setenv=DISPLAY=$DISPLAY -D ~/kicksecure-xfce-chroot /sbin/init

Exit systemd-nspawn Chroot[edit]

To leave the chroot press keep holding key CTRL and press key 5 quickly 3 times within 1 second. [7]

Limitations of systemd-nspawn based Chroot[edit]

Despite these limitations, systemd-nspawn should probably preferred over classic chroot. Depends on what you are trying to accomplish.

  • sdwdate (and Boot Clock Randomization) cannot work inside systemd-nspawn.
  • Tor will fail to start inside systemd-nspawn chroot if Tor is already running on the host in default config (local listen post 9050). But that shouldn't matter. The systemd-nspawn chroot will use the host's Tor in this case. systemd-nspawn has also option to run private networking but these have not been researched for Kicksecure yet.

Footnotes[edit]

  1. ↑
    • apt-transport-https is required for some older Debian based Linux distributions that have not integrated https support into APT yet. If not available in your distribution, can be safely ignored.
    • apt-transport-tor is required because /etc/apt/sources.list.d/debian.listarchive.org is using tor+https. Otherwise we would see the following error.
    I: cleaning package lists and apt cache...
Reading package lists...
E: The method driver /usr/lib/apt/methods/tor+https could not be found.
E: The method driver /usr/lib/apt/methods/tor+https could not be found.
E: The method driver /usr/lib/apt/methods/tor+https could not be found.
E: Failed to fetch tor+https://deb.debian.org/debian-security/dists/buster/updates/InRelease
E: Failed to fetch tor+https://deb.debian.org/debian/dists/buster/InRelease
E: Failed to fetch tor+https://deb.kicksecure.com/dists/buster-developers/InRelease
E: Some index files failed to download. They have been ignored, or old ones used instead.
E: apt --option Dir::Etc::SourceList=/dev/null update -oAPT::Status-Fd=<$fd> -oDpkg::Use-Pty=false failed
    • tor is required so apt-transport-tor can use Tor. Otherwise we would see the following error.
    I: cleaning package lists and apt cache...
Err:1 tor+https://deb.debian.org/debian-security buster/updates InRelease
  Could not connect to 127.0.0.1:9050 (127.0.0.1). - connect (111: Connection refused)
Err:2 tor+https://deb.debian.org/debian buster InRelease
  Unable to connect to 127.0.0.1:9050:
Err:3 tor+https://deb.kicksecure.com buster-developers InRelease
  Could not connect to 127.0.0.1:9050 (127.0.0.1). - connect (111: Connection refused)
Reading package lists...
W: Failed to fetch tor+https://deb.debian.org/debian-security/dists/buster/updates/InRelease  Could not connect to 127.0.0.1:9050 (127.0.0.1). - connect (111: Connection refused)
W: Failed to fetch tor+https://deb.debian.org/debian/dists/buster/InRelease  Unable to connect to 127.0.0.1:9050:
W: Failed to fetch tor+https://deb.kicksecure.com/dists/buster-developers/InRelease  Could not connect to 127.0.0.1:9050 (127.0.0.1). - connect (111: Connection refused)
W: Some index files failed to download. They have been ignored, or old ones used instead.
    • Actually package apt-transport-tor recommends package tor but listing it here anyhow for those using APT with parameter --no-install-recommends.
    • apt-transport-https is suggested below to download the signing key.
  2. ↑ See Secure Downloads to understand why curl and the parameters --tlsv1.3 are used instead of wget.

    Placing an additional signing key into folder /usr/share/keyrings by itself alone has no impact on security as this folder is not automatically used by Debian's APT by default. Only when an APT sources list configuration file points to folder /usr/share/keyrings using the signed-by keyword the signing key will be actually used. Therefore deleting keys in /usr/share/keyrings is optional if intending to disable an APT repository. See also APT Signing Key Folders.
  3. ↑ Fixed in mmdebstrap 0.5.0. Quote changelogarchive.org:

    do not copy /etc/resolv.conf or /etc/hostname if the host system doesn't have them

    Therefore no longer required in Debian bullseye.

  4. ↑ No longer working. apt_cacher_ng_maybe="--aptopt='Acquire::http { Proxy \"http://127.0.0.1:3142\"; }' --aptopt='Acquire::https { Proxy \"http://127.0.0.1:3142\"; }' --aptopt='Acquire::tor { Proxy \"http://127.0.0.1:3142\"; }'"
  5. ↑
    • debootstrap cannot be used since it is a single-mirror Debian chroot creation tool. I.e. it cannot use multiple APT repositories at the same time. And Kicksecure APT repository does not ships no packages available from packages.debian.org. Therefore using mmdebstrap which is a multi-mirror Debian chroot creation.
      • If you cannot use mmdebstrap either (cross platform builds?), you could first create a Debian chroot using debootstrap (or anything) and then install a Kicksecure meta package manually inside the chroot.
    • Whonix: add anon_shared_inst_tb=open
  6. ↑ During chroot build process the following files were already created.
    • /etc/apt/sources.list.d/debian.list
    • /etc/apt/sources.list.d/derivative.list
  7. ↑ https://unix.stackexchange.com/questions/577065/connected-to-container-mycontainer-press-three-times-within-1s-to-exit-sessiarchive.org

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