Running glibc programs: Difference between revisions

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This is a draft<br>
If you want to run [https://www.gnu.org/software/libc/ glibc] programs in Alpine Linux, there are a few ways of doing so. You can install the [https://git.adelielinux.org/adelie/gcompat gcompat] compatibility layer, you can install glibc alongside [https://musl.libc.org/ musl] (manually, as it isn't packaged), or you could do it the easy way and use either Flatpak (the easiest), containers or a chroot.<br>


If you want to run glibc programs under alpine there are a few ways to do so.You could install glibc additional to uclibc (you would have to do this manualy) or you could do the easy way and use a chroot.<br>
Because there are different use cases, this is just a slight overview about what's possible and what's sensible.<br>
Because there are different usecases I want to give a slight overview about what's possible and what is intelligent.<br>


==Your options==
= Your options =
===Using Busybox===
First the most simple approach for setting up a chroot is using a glibc build of busybox.<br>
This approach has just a few downsides:<br>
- You have to link most /bin/ and /usr/bin program against /bin/busybox and some busybox builds break if you don't configure it right.<br>
- You have to manually download every library you need for your program manually.<br><br>
But if you want a small enviroment for one simple use case this is the solution you want.


===Using a livecd===
== gcompat ==
If you prefer any special distri you can always download and extract a livecd and use it as a chroot enviroment.


===Using a stage3 gentoo archive===
gcompat is the go-to compatibility layer for Alpine users.
This is the fastest approach and you have the advantage of controlling which package version of which library you will install.<br>
Drawbacks are as follow:<br>
- Big build.You have to install a portage tree which uses up a lot of space.(It's not 100% necessary if you don't have to install any additional content you don't need it)<br>
- On slow mashines not recommended because you have to compile your packages.<br>


===Using Archlinux or Debian===
{{cmd|apk add {{pkg|gcompat}}}}
If you want a nice running system you can install Arch or Debian in a chroot.This approach isn't as easily executed as the other alternatives, but are in my opinion the cleanest and most recommended for the every day user.


==How to do it==
After that you run your binaries as normal.
Like I said this is just a quick draft so here it comes.
===Using Busybox===
First we need to download busybox.You can choose any of your favourit distros to download a prebuild version.I for instance would use Archlinux packages from http://www.archlinux.org/packages/community/i686/busybox/.<br>
wget http://www.archlinux.org/packages/community/i686/busybox/download/ -O busybox.pkg.tar.xz
wget http://www.archlinux.org/packages/core/i686/glibc/download/ -O glibc.pkg.tar.xz
for i in *.pkg.tar.xz;do
bsdtar xfJ $i -C ~/chroot
done
mkdir -p ~/chroot/usr/bin/ ~/chroot/{dev,proc,root,etc}
ln -s /bin/busybox ~/chroot/bin/sh
ln -s /bin/busybox ~/chroot/bin/ln
sudo chroot ~/chroot/ /bin/sh


This creates a simple chroot enviroment which we will expand through all commands included in busybox.
== Flatpak ==
for i in $(busybox --list);do ln -s /bin/busybox /usr/bin/$i;done


===Using a livecd===
Flatpak is by far the easiest method of running any graphical glibc program on Alpine.
WIP
Firstly install it.


===Using a stage3 tar archive===
  {{cmd|apk add {{pkg|flatpak}}}}
Select a mirror from http://www.gentoo.org/main/en/mirrors2.xml , switch to /releases/x86/current-stage3/ and download the latest tar ball (for me stage3-i686-20120124.tar.bz2 ).
  wget http://de-mirror.org/gentoo/releases/x86/current-stage3/stage3-i686-20120124.tar.bz2
mkdir ~/chroot
tar xfj stage3-i686-*.tar.bz2 -C ~/chroot
sudo chroot ~/chroot
And voila you got your working gentoo chroot.<br>
You can now take a look at http://www.gentoo.org/doc/en/?catid=desktop to find out how you can configure and install your system or simply extract/copy the program you need to run in your chroot enviroment and execute it.


===Using Archlinux or Debian===
Then you can run any Flatpak application:
WIP


==Example==
{{cmd|flatpak run <flatpak name>}}
Here will be an example of how to use a chroot.
 
It is recommended to enable [https://flathub.org Flathub] using its instructions [https://flatpak.org/setup/Alpine/ here], as most glibc programs you might need will be packaged there.
 
You can then install applications from it, for example:
 
{{cmd|flatpak install com.valvesoftware.Steam}}
 
== Chroot ==
 
An option that's easier to generalize to other glibc applications is installing a glibc-based distribution into a chroot. You can then either chroot into it, or use a symlink and some configuration to make its glibc (and associated libraries) usable from Alpine.
 
After setting up a chroot using any of the methods described below, the loader can be set up in Alpine like so (these instructions are for a Debian chroot in /var/chroots/debian, on x86_64, but can be adapted to other systems by using the appropriate paths):
 
{{cmd|mkdir -p /lib64
ln -s /var/chroots/debian/lib/x86_64-linux-gnu/ld-2.33.so /lib64
printf '/var/chroots/debian/lib/x86_64-linux-gnu\n/var/chroots/debian/usr/lib/x86_64-linux-gnu\n' > /etc/ld.so.conf
/var/chroots/debian/sbin/ldconfig}}
 
=== Gentoo Linux ===
 
Select a stage3 from [https://www.gentoo.org/downloads/ here] and portage latest from [https://www.gentoo.org/downloads/mirrors/ here] at gentoo/snapshots/portage-latest.tar.xz.
 
First,
 
{{cmd|doas apk add {{pkg|xz}}}}
 
Enter the chroot:
{{cmd|mkdir ~/chroot
cd ~/chroot
tar -xvf stage3-*.tar.xz
tar -xvf portage-latest.tar.xz
mv portage usr
doas mount --bind /dev dev
doas mount --bind /sys sys
doas mount -t proc proc proc
cp /etc/resolv.conf etc
doas chroot . /bin/bash}}
 
And voilà, you have your working Gentoo chroot!<br>
 
You can now take a look at [https://wiki.gentoo.org/wiki/Handbook:Main_Page Gentoo's Handbook] to find out how you can configure and install your system, or simply extract/copy the program you need to run in your chroot enviroment and execute it.
 
Here is a wrapper script that is similar to <code>arch-chroot</code> when you frequently reuse this chroot:
 
Also, create an account with the same user name as host current user to the chroot or make changes to the userspec option to chroot line.
 
{{Cat|gentoo-chroot.sh|<nowiki>!/bin/bash
CHROOT_PATH="/home/$USER/chroot"
cd $CHROOT_PATH
mount | grep $CHROOT_PATH/dev || doas mount --bind /dev dev
mount | grep $CHROOT_PATH/sys || doas mount --bind /sys sys
mount | grep $CHROOT_PATH/proc || doas mount -t proc proc proc
cp /etc/resolv.conf etc
doas chroot --userspec=$USER:users . /bin/bash
echo "You must manually unmount $CHROOT_PATH/dev, $CHROOT_PATH/sys, $CHROOT_PATH/proc."
</nowiki>
}}
 
Do at <code>chmod +x gentoo-chroot.sh</code> to get it to work.
 
=== Arch Linux ===
 
Either use '''pacstrap''' (included with the arch-install-scripts package) or an Arch bootstrap image:
 
{{cmd|doas apk add {{pkg|arch-install-scripts}}
mkdir ~/chroot && cd ~/chroot
curl -O https://mirrors.edge.kernel.org/archlinux/iso/latest/archlinux-bootstrap-x86_64.tar.gz
doas tar xzf archlinux-bootstrap-x86_64.tar.gz && rm archlinux-bootstrap-x86_64.tar.gz
doas sed -i '/evowise/s/^#//' root.x86_64/etc/pacman.d/mirrorlist
doas sed -i '/CheckSpace/s/^/#/' root.x86_64/etc/pacman.conf
doas arch-chroot root.x86_64
[chroot]# pacman-key --init
[chroot]# pacman-key --populate archlinux}}
 
Once that is done, update the system and install the desired package(s) (denoted by ''"foo"'' in this example):
 
{{cmd|[chroot]# pacman -Syu ''foo''}}
 
=== Debian ===
{{todo|gresec referencs need to be cleanly removed from this section.}}
Use the provided debootstrap package to create the Debian chroot. <code>--arch</code> is optional, depending of your needs.
 
On the '''linux-grsec''' kernel, you will need to relax chroot limitations:
 
  sudo apk add debootstrap
  for i in /proc/sys/kernel/grsecurity/chroot_*; do echo 0 | sudo tee $i; done
  mkdir ~/chroot
  sudo debootstrap --arch=i386 wheezy ~/chroot https://deb.debian.org/debian/
  for i in /proc/sys/kernel/grsecurity/chroot_*; do echo 1 | sudo tee $i; done
  sudo chroot ~/chroot /bin/bash
 
You can now use <code>apt-get</code> to install needed packages.
 
== Containers ==
 
It's also possible to use Docker or Podman containers with a helper like Distrobox. This allows using graphical programs easily and doesn't require root privileges once set up.
 
{{cmd|# apk add {{pkg|distrobox}}}}
 
=== Distrobox + Podman ===
 
{{cmd|# apk add {{pkg|podman}}}}
 
Then set up rootless Podman, following [[Podman|these steps]].
You'll need to mount your root as shared for Distrobox to function.
 
Fill in {{path|/etc/local.d/mount-rshared.start}} like so:
 
{{cmd|#!/bin/sh
mount --make-rshared /}}
 
Mark it as executable.
 
{{cmd|# chmod +x /etc/local.d/mount-rshared.start}}
 
Then autostart its service.
 
{{cmd|# rc-update add local default
&#35; rc-service local start}}
 
Finally you can create a container using your chosen image.
 
{{cmd|$ distrobox create --image debian --name debian
$ distrobox enter debian}}
 
It may also be necessary to allow X authorization for GUI programs to work.
 
{{cmd|$ xhost +si:localuser:$USER}}
 
== Chroot + Bubblewrap ==
 
It's also possible to use a Debian system chroot with Bubblewrap. This allows running programs without root.
 
{{cmd|# apk add bubblewrap debootstrap
&#35; mkdir -p /var/chroots/debian
&#35; debootstrap --arch amd64 stable /var/chroots/debian/ https://deb.debian.org/debian}}
 
Finally we can make an alias for bwrap.
 
{{cmd|$ alias glibc{{=}}"LANG{{=}}en_US.UTF-8 bwrap --bind /var/chroots/debian / --dev-bind /dev /dev --proc /proc --bind /sys /sys --bind /run /run --bind /home /home --ro-bind /etc/resolv.conf /etc/resolv.conf --ro-bind /etc/passwd /etc/passwd --ro-bind /etc/group /etc/group"}}
 
To run programs that use X11/Xorg you can use:
{{cmd|$ alias glibcX11{{=}}"LANG{{=}}en_US.UTF-8 bwrap --bind /var/chroots/debian / --dev-bind /dev /dev --proc /proc --bind /sys /sys --bind /run /run --bind /home /home --ro-bind /etc/resolv.conf /etc/resolv.conf --ro-bind /etc/passwd /etc/passwd --ro-bind /etc/group /etc/group --bind /tmp/.X11-unix/X0 /tmp/.X11-unix/X0 --setenv DISPLAY :0"}}
 
In this case you might need to use xhost to allow local connections, e.g.:
{{cmd|# xhost + local:}}
 
Now we can invoke glibc-built binaries like so:
{{cmd|$ glibc ./binary}} or {{cmd|$ glibcX11 ./binary}}
 
For updating the Chroot or installing dependencies we can mount it and then login as root:
{{cmd|# mount --bind /dev /var/chroots/debian/dev
&#35; mount --bind /proc /var/chroots/debian/proc
&#35; chroot /var/chroots/debian /bin/bash
&#35; apt update && apt upgrade}}
 
After installing what you might want to umount the binds for dev and proc to avoid issues.
{{cmd|# umount /var/chroots/debian/dev}}
{{cmd|# umount /var/chroots/debian/proc}}
 
[[Category:Development]]
[[Category:Installation]]

Latest revision as of 20:15, 6 March 2024

If you want to run glibc programs in Alpine Linux, there are a few ways of doing so. You can install the gcompat compatibility layer, you can install glibc alongside musl (manually, as it isn't packaged), or you could do it the easy way and use either Flatpak (the easiest), containers or a chroot.

Because there are different use cases, this is just a slight overview about what's possible and what's sensible.

Your options

gcompat

gcompat is the go-to compatibility layer for Alpine users.

apk add gcompat

After that you run your binaries as normal.

Flatpak

Flatpak is by far the easiest method of running any graphical glibc program on Alpine. Firstly install it.

apk add flatpak

Then you can run any Flatpak application:

flatpak run <flatpak name>

It is recommended to enable Flathub using its instructions here, as most glibc programs you might need will be packaged there.

You can then install applications from it, for example:

flatpak install com.valvesoftware.Steam

Chroot

An option that's easier to generalize to other glibc applications is installing a glibc-based distribution into a chroot. You can then either chroot into it, or use a symlink and some configuration to make its glibc (and associated libraries) usable from Alpine.

After setting up a chroot using any of the methods described below, the loader can be set up in Alpine like so (these instructions are for a Debian chroot in /var/chroots/debian, on x86_64, but can be adapted to other systems by using the appropriate paths):

mkdir -p /lib64 ln -s /var/chroots/debian/lib/x86_64-linux-gnu/ld-2.33.so /lib64 printf '/var/chroots/debian/lib/x86_64-linux-gnu\n/var/chroots/debian/usr/lib/x86_64-linux-gnu\n' > /etc/ld.so.conf /var/chroots/debian/sbin/ldconfig

Gentoo Linux

Select a stage3 from here and portage latest from here at gentoo/snapshots/portage-latest.tar.xz.

First,

doas apk add xz

Enter the chroot:

mkdir ~/chroot cd ~/chroot tar -xvf stage3-*.tar.xz tar -xvf portage-latest.tar.xz mv portage usr doas mount --bind /dev dev doas mount --bind /sys sys doas mount -t proc proc proc cp /etc/resolv.conf etc doas chroot . /bin/bash

And voilà, you have your working Gentoo chroot!

You can now take a look at Gentoo's Handbook to find out how you can configure and install your system, or simply extract/copy the program you need to run in your chroot enviroment and execute it.

Here is a wrapper script that is similar to arch-chroot when you frequently reuse this chroot:

Also, create an account with the same user name as host current user to the chroot or make changes to the userspec option to chroot line.

Contents of gentoo-chroot.sh

!/bin/bash CHROOT_PATH="/home/$USER/chroot" cd $CHROOT_PATH mount | grep $CHROOT_PATH/dev || doas mount --bind /dev dev mount | grep $CHROOT_PATH/sys || doas mount --bind /sys sys mount | grep $CHROOT_PATH/proc || doas mount -t proc proc proc cp /etc/resolv.conf etc doas chroot --userspec=$USER:users . /bin/bash echo "You must manually unmount $CHROOT_PATH/dev, $CHROOT_PATH/sys, $CHROOT_PATH/proc."

Do at chmod +x gentoo-chroot.sh to get it to work.

Arch Linux

Either use pacstrap (included with the arch-install-scripts package) or an Arch bootstrap image:

doas apk add arch-install-scripts mkdir ~/chroot && cd ~/chroot curl -O https://mirrors.edge.kernel.org/archlinux/iso/latest/archlinux-bootstrap-x86_64.tar.gz doas tar xzf archlinux-bootstrap-x86_64.tar.gz && rm archlinux-bootstrap-x86_64.tar.gz doas sed -i '/evowise/s/^#//' root.x86_64/etc/pacman.d/mirrorlist doas sed -i '/CheckSpace/s/^/#/' root.x86_64/etc/pacman.conf doas arch-chroot root.x86_64 [chroot]# pacman-key --init [chroot]# pacman-key --populate archlinux

Once that is done, update the system and install the desired package(s) (denoted by "foo" in this example):

[chroot]# pacman -Syu foo

Debian

Todo: gresec referencs need to be cleanly removed from this section.


Use the provided debootstrap package to create the Debian chroot. --arch is optional, depending of your needs.

On the linux-grsec kernel, you will need to relax chroot limitations:

 sudo apk add debootstrap
 for i in /proc/sys/kernel/grsecurity/chroot_*; do echo 0 | sudo tee $i; done
 mkdir ~/chroot
 sudo debootstrap --arch=i386 wheezy ~/chroot https://deb.debian.org/debian/
 for i in /proc/sys/kernel/grsecurity/chroot_*; do echo 1 | sudo tee $i; done
 sudo chroot ~/chroot /bin/bash

You can now use apt-get to install needed packages.

Containers

It's also possible to use Docker or Podman containers with a helper like Distrobox. This allows using graphical programs easily and doesn't require root privileges once set up.

# apk add distrobox

Distrobox + Podman

# apk add podman

Then set up rootless Podman, following these steps. You'll need to mount your root as shared for Distrobox to function.

Fill in /etc/local.d/mount-rshared.start like so:

#!/bin/sh mount --make-rshared /

Mark it as executable.

# chmod +x /etc/local.d/mount-rshared.start

Then autostart its service.

# rc-update add local default # rc-service local start

Finally you can create a container using your chosen image.

$ distrobox create --image debian --name debian $ distrobox enter debian

It may also be necessary to allow X authorization for GUI programs to work.

$ xhost +si:localuser:$USER

Chroot + Bubblewrap

It's also possible to use a Debian system chroot with Bubblewrap. This allows running programs without root.

# apk add bubblewrap debootstrap # mkdir -p /var/chroots/debian # debootstrap --arch amd64 stable /var/chroots/debian/ https://deb.debian.org/debian

Finally we can make an alias for bwrap.

$ alias glibc="LANG=en_US.UTF-8 bwrap --bind /var/chroots/debian / --dev-bind /dev /dev --proc /proc --bind /sys /sys --bind /run /run --bind /home /home --ro-bind /etc/resolv.conf /etc/resolv.conf --ro-bind /etc/passwd /etc/passwd --ro-bind /etc/group /etc/group"

To run programs that use X11/Xorg you can use:

$ alias glibcX11="LANG=en_US.UTF-8 bwrap --bind /var/chroots/debian / --dev-bind /dev /dev --proc /proc --bind /sys /sys --bind /run /run --bind /home /home --ro-bind /etc/resolv.conf /etc/resolv.conf --ro-bind /etc/passwd /etc/passwd --ro-bind /etc/group /etc/group --bind /tmp/.X11-unix/X0 /tmp/.X11-unix/X0 --setenv DISPLAY :0"

In this case you might need to use xhost to allow local connections, e.g.:

# xhost + local:

Now we can invoke glibc-built binaries like so:

$ glibc ./binary

or

$ glibcX11 ./binary

For updating the Chroot or installing dependencies we can mount it and then login as root:

# mount --bind /dev /var/chroots/debian/dev # mount --bind /proc /var/chroots/debian/proc # chroot /var/chroots/debian /bin/bash # apt update && apt upgrade

After installing what you might want to umount the binds for dev and proc to avoid issues.

# umount /var/chroots/debian/dev

# umount /var/chroots/debian/proc