Difference between revisions of "Running glibc programs"

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m (Chroot method: recommend putting the command at the top)
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{{Draft}}
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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 could install glibc as additional to [https://musl.libc.org/ musl] (you would have to do this manually), or you could do it the easy way and use either Flatpak (the easiest) or a chroot.<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 could install glibc as additional to [https://uclibc.org/about.html uclibc] (you would have to do this manually), or you could do it 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 intelligent.<br>
 
Because there are different use cases, this is just a slight overview about what's possible and what's intelligent.<br>
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= Your options =
 
= Your options =
  
== Using BusyBox ==
+
== Flatpak ==
 
 
First, the simplest approach for setting up a chroot is by using a glibc build of [https://www.busybox.net/about.html BusyBox].
 
 
 
This approach has just a few downsides:-
 
* You have to link most <code>/bin/</code> and <code>/usr/bin</code> programs against <code>/bin/busybox</code>, and some BusyBox builds break if you don't configure them correctly.
 
* You have to manually download every library you need for your program manually.
 
  
However, if you want a small environment for one simple use case, then this is the solution you want.
+
Flatpak is by far the easiest method of running any graphical glibc program on Alpine.
 +
Firstly install it.
  
== Using a live CD ==
+
sudo apk add flatpak
  
If you prefer using any special distro, you can always download and extract a live CD and use it as a chroot enviroment.
+
Then you can run any Flatpak application:
  
== Using an image ==
+
flatpak run <flatpak name>
  
For Gentoo, it is the slowest approach especially on slow machines since it is not binary distribution and can be indecisive, but you have the advantage of controlling the package version of whichever library you will install. A drawback would be a 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 that you won't need.)  Sometimes the package will fail on compilation phase of emerge.  You either end up patching it yourself or waiting for a fix to appear on their Bugzilla from an experienced user.
+
It is recommended to enable [https://flathub.org Flathub] using it's instructions [https://flatpak.org/setup/Alpine/ here], as most glibc programs you might need will be packaged there.
  
For Arch or Debian, it is recommended since packages are precompiled and better at unattended package installation.  This approach isn't as easily executed as the other alternatives, but this may be the cleanest and most recommended one for the every day user.
+
You can then install applications from it, for example:
  
= How to do it =
+
flatpak install com.valvesoftware.Steam
  
This is just a quick draft, so here it comes.
+
== Chroot ==
 
 
== Using BusyBox ==
 
 
 
First, we need to download BusyBox.  You can choose any of your favourite distros to download a prebuilt version.  For instance, you could use Arch Linux [https://www.archlinux.org/packages/?q=busybox packages], as follows:
 
 
 
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
 
mkdir -p ~/chroot/usr/bin/ ~/chroot/{dev,proc,root,etc}
 
for i in *.pkg.tar.xz;do
 
bsdtar xfJ $i -C ~/chroot
 
done
 
cp /etc/resolv.conf ~/chroot/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 the commands included in BusyBox:
 
 
 
for i in $(busybox --list);do ln -s /bin/busybox /usr/bin/$i;done
 
 
 
 
 
== Using a live CD ==
 
{{Draft|Contributions welcome}}
 
 
 
 
 
== Using an image ==
 
  
 
=== Gentoo Linux ===
 
=== Gentoo Linux ===
Line 65: Line 32:
  
 
  sudo apk add xz
 
  sudo apk add xz
 
You also may need the vanilla kernel.  If any time Gentoo decides to update PAM, you need it for it to emerge successfully without problems.
 
 
sudo apk add kernel-vanilla
 
 
Add the kernel-vanilla to Grub and reboot with the vanilla kernel if you are going to pull in both git and layman which they use to download user community supported packages.
 
  
 
Enter the chroot:
 
Enter the chroot:
Line 108: Line 69:
 
=== Arch Linux ===
 
=== Arch Linux ===
  
Although '''pacstrap''' is included with the arch-install-scripts package, it will not work unless the target directory is a mountpoint, so the Arch bootstrap image must be used instead (the image is updated every month, so change the date in the link as required):
+
Either use '''pacstrap''' (included with the arch-install-scripts package) or an Arch bootstrap image:
  
 
   sudo apk add arch-install-scripts
 
   sudo apk add arch-install-scripts
 
   mkdir ~/chroot && cd ~/chroot
 
   mkdir ~/chroot && cd ~/chroot
   curl -O https://mirrors.kernel.org/archlinux/iso/latest/archlinux-bootstrap-2018.01.01-x86_64.tar.gz
+
   curl -O https://mirrors.edge.kernel.org/archlinux/iso/latest/archlinux-bootstrap-2021.04.01-x86_64.tar.gz
   tar xzf archlinux-bootstrap-2018.01.01-x86_64.tar.gz && rm archlinux-bootstrap-2018.01.01-x86_64.tar.gz
+
   sudo tar xzf archlinux-bootstrap-2021.04.01-x86_64.tar.gz && rm archlinux-bootstrap-2021.04.01-x86_64.tar.gz
   sed -i '/evowise/s/^#//' root.x86_64/etc/pacman.d/mirrorlist
+
   sudo sed -i '/evowise/s/^#//' root.x86_64/etc/pacman.d/mirrorlist
 +
  sudo sed -i '/CheckSpace/s/^/#/' root.x86_64/etc/pacman.conf
 
   sudo arch-chroot root.x86_64
 
   sudo arch-chroot root.x86_64
 
   [chroot]# pacman-key --init
 
   [chroot]# pacman-key --init
Line 137: Line 99:
  
 
You can now use <code>apt-get</code> to install needed packages.
 
You can now use <code>apt-get</code> to install needed packages.
 
== Examples ==
 
 
=== Source dedicated server ===
 
 
Here is an easy example of how you can run [http://www.srcds.com srcds] in a simple BusyBox chroot.
 
 
For this server, you will only need the basic chroot and an advanced tar version (the BusyBox version is not sufficient because of the missing -U command):
 
 
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
 
wget http://www.archlinux.org/packages/core/i686/tar/download/ -O tar.pkg.tar.xz
 
mkdir -p ~/chroot/usr/bin/ ~/chroot/{dev,proc,root,etc}
 
for i in *.pkg.tar.xz;do
 
bsdtar xfJ $i -C ~/chroot
 
done
 
cp /etc/resolv.conf ~/chroot/etc/
 
ln -s /bin/busybox ~/chroot/bin/sh
 
ln -s /bin/busybox ~/chroot/bin/ln
 
sudo chroot ~/chroot/ /bin/sh
 
 
Now that you are in a working chroot, you can download the server and install it.  You just have to execute the following self-explaining commands...
 
 
mkdir ~/work
 
cd ~/work
 
busybox wget http://www.steampowered.com/download/hldsupdatetool.bin
 
chmod +x hldsupdatetool.bin
 
ln -s /bin/busybox ./uncompress
 
cp /bin/tar . #right now executing programs from $PATH is buggy, soon to be fixed (no bug in BusyBox, but in my script)
 
./hdsupdatetool.bin #you can accept it or not ;)
 
./steam
 
./steam
 
 
...and you should have a working chroot with '''srcds''' installed in it.
 
 
If you think you are clever or elegant, you can use the server with a bash script:
 
 
#!/bin/bash
 
chroot ~/chroot /root/work/steam $@
 
 
Just save it (in your Alpine installation) under <code>/usr/bin/steam</code>, do a <code>chmod +x /usr/bin/steam</code> and have fun!
 
 
{{Warning|This script would let '''Steam''' run with root priviliges.  This is not recommended.}}
 
 
=== MegaCli ===
 
 
So let's run [https://wikitech.wikimedia.org/wiki/MegaCli MegaCli] in a chroot too, shall we? ;)
 
 
First we set up a uclibc chroot :)
 
 
'''MegaCli''' needs more than just glibc.  It needs [https://www.gnu.org/software/ncurses/ ncurses] and the gcc-libs:
 
 
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
 
wget http://www.archlinux.org/packages/core/i686/ncurses/download/ -O ncurses.pkg.tar.xz
 
wget http://www.archlinux.org/packages/core/i686/gcc-libs/download/ -O gcc-libs.pkg.tar.xz
 
mkdir -p ~/chroot/usr/bin/ ~/chroot/{dev,proc,root,etc,sys}
 
cp /etc/resolv.conf ~/chroot/etc/
 
for i in *.pkg.tar.xz;do
 
bsdtar xfJ $i -C ~/chroot
 
done
 
ln -s /bin/busybox ~/chroot/bin/sh
 
ln -s /bin/busybox ~/chroot/bin/ln
 
 
After this, we visit [http://www.lsi.com/downloads/Public/MegaRAID%20Common%20Files/8.02.16_MegaCLI.zip this] site and download '''8.02.16_MegaCLI.zip'''.
 
 
mkdir tmp
 
cd tmp
 
unzip ../8.02.16_MegaCLI.zip
 
cd LINUX
 
unzip MegaCliLin.zip
 
#Now comes code stolen from rpm2cpio
 
o=`expr 96 + 8`
 
set `od -j $o -N 8 -t u1 MegaCli-8.02.16-1.i386.rpm`
 
il=`expr 256 \* \( 256 \* \( 256 \* $2 + $3 \) + $4 \) + $5`
 
dl=`expr 256 \* \( 256 \* \( 256 \* $6 + $7 \) + $8 \) + $9`
 
sigsize=`expr 8 + 16 \* $il + $dl`
 
o=`expr $o + $sigsize + \( 8 - \( $sigsize \% 8 \) \) \% 8 + 8`
 
set `od -j $o -N 8 -t u1 MegaCli-8.02.16-1.i386.rpm`
 
il=`expr 256 \* \( 256 \* \( 256 \* $2 + $3 \) + $4 \) + $5`
 
dl=`expr 256 \* \( 256 \* \( 256 \* $6 + $7 \) + $8 \) + $9`
 
hdrsize=`expr 8 + 16 \* $il + $dl`
 
o=`expr $o + $hdrsize`
 
dd if=MegaCli-8.02.16-1.i386.rpm ibs=$o skip=1 2>/dev/null |bsdtar -xf -
 
#wow ...
 
rm opt/MegaRAID/MegaCli/MegaCli64 # who needs 64bit?
 
cp -r opt/ ~/chroot/
 
 
Now we have a working '''MegaCli''' client in our chroot.
 
 
As with '''srcds''', we do not want to operate from inside the chroot, so here is a little script that should ease you up (use at your own risk):
 
 
#!/bin/bash
 
user=$(whoami)
 
if [ "$user" != "root" ];then
 
echo "This script needs root access"
 
exit
 
fi
 
mount -t proc proc ~/chroot/proc/
 
mount --bind /dev/ ~/chroot/dev/
 
mount --bind /sys/ ~/chroot/sys/
 
#we may need dev and maybe proc too to use this program
 
chroot ~/chroot /opt/MegaRAID/MegaCli/MegaCli $@
 
umount ~/chroot/proc
 
umount ~/chroot/dev
 
umount ~/chroot/sys
 
 
Save it under <code>/usr/bin/MegaCli</code>.  Do a <code>chmod +x /usr/bin/MegaCli</code> and good luck.
 
 
Note:  This method takes around 50mb.  If you need something smaller, then you can strip a few files from glibc (not recommended), or work on a squashfs.
 
 
With the following, you can create a squashfs that is around 15mb small:
 
mksquashfs ~/chroot/ /chroot.sfs -b 65536
 
 
When you add a [https://en.wikipedia.org/wiki/UnionFS unionfs] layer, you can even use it with write access, or you can bind some directories to the writeable directories before you chroot into it.
 
 
I will look into it later on.
 
 
You can save the chroot in another directory than your home directory, and you can even install a chroot through an APKBUILD (after someone wrote it).
 
 
With this, you could use many glibc-dependent programs through one chroot, but be aware that running programs like this should not be standard.  This should only be used in extreme situations, as in _closed source_ tools linked against glibc.
 
 
=== Skype on Debian chroot ===
 
 
{{Draft|Not yet validated}}
 
 
This is an example on how to run '''Skype''' from a Debian 32b chroot.
 
 
  sudo chroot ~/chroot
 
  wget http://www.skype.com/go/getskype-linux-deb
 
  dpkg -i getskype-linux-deb
 
 
To fix missing dependencies, you will want to use:
 
 
  apt-get -f install
 
 
Then, exit the chroot:
 
 
  exit
 
 
Fix PAX flags on Skype binary - '''linux-grsec''' only.
 
 
ELF marking with paxctl cannot be used because Skype binary refuses to run if modified.
 
 
<code>CONFIG_PAX_XATTR_PAX_FLAGS</code> is NOT yet available in '''linux-grsec'''.
 
 
  sudo apk add attr
 
  sudo setfattr -n user.pax.flags -v "em" ~/chroot/usr/bin/skype
 
 
Mount needed directories in the chroot read-only to limit access to the system devices.
 
 
Give write access to <code>/dev/v4l</code> and to <code>/dev/snd</code> in order to let Skype use the webcam device:  Skype is not compatible with Alsa anymore and requires Pulseaudio to be running.
 
 
  sudo mount -o bind /proc ~/chroot/proc
 
  sudo mount -o bind,ro,remount /proc ~/chroot/proc
 
  sudo mount -o bind /sys ~/chroot/sys
 
  sudo mount -o bind,ro,remount /sys ~/chroot/sys
 
  sudo mount -o bind /dev ~/chroot/dev
 
  sudo mount -o bind,ro,remount /dev ~/chroot/dev
 
  sudo mount -o bind /dev/v4l ~/chroot/dev/v4l
 
  sudo mount -t tmpfs -o nodev,nosuid,noexec shm $CHROOT_PATH/dev/shm
 
 
Enter the chroot and create a user:
 
 
  sudo chroot ~/chroot
 
  useradd -G audio,video <username>
 
  exit
 
 
Then run Skype as your newly created user:
 
 
  sudo chroot ~/chroot /bin/su - <username> -c /usr/bin/skype
 
 
 
=== Dungeon Crawl (Stone Soup) on Arch ===
 
 
Once the Arch system is laid down (to <code>~/chroot/root.x86_64</code> in this example), install the game:
 
 
  sudo arch-chroot ~/chroot/root.x86_64
 
  [chroot]# pacman -Syu crawl-tiles
 
 
Then exit the chroot and run it with this command:
 
 
  sudo arch-chroot ~/chroot/root.x86_64 /bin/su -c 'DISPLAY=:0 crawl-tiles'
 
 
A separate user can also be created to run the game, if preferred.
 
 
 
=== Spotify ===
 
 
==== Docker method ====
 
 
Read the [[Docker]] page to install it.  Then clone the repository, as shown below.  It will automate the process of pulling all the dependencies, and '''PaX''' marks it for the hardened kernel.  The advantage of this container is that it is ready-to-use and has stripped down many of the <code>/usr/bin</code> executables.  The downside is that is unstable.
 
 
git clone https://github.com/orsonteodoro/docker-arch-spotify-PaXmarked
 
 
Follow the instructions in the <code>README.md</code>
 
 
==== Chroot method ====
 
 
The Chroot method the preferred method;  it doesn't have the black screen bug and is more stable.  Just translate the [https://github.com/orsonteodoro/docker-arch-spotify-PaXmarked/blob/master/Dockerfile Dockerfile instructions] into native '''sh''' (Bourne shell).  The trick again is to run Spotify as root with sudo inside the chroot – not as regular user. 
 
 
Use <code>sudo aplay -l</code> to verify that the soundcard is detected.  When you use either this or the Docker method, which relies on ALSA, there could be a conflict depending on who grabs the sound card.  Stop all browsers or programs using the sound device outside of the chroot or the docker image so that Spotify can use it.
 
 
I did some translation.  You may need to make changes.
 
 
To update, just delete it and call <code>alpine-spotify-installer.sh</code> again.  You will still need the Arch Linux bootstrap image.  Extract the image.  Next, copy and paste the code shown below into root.x86_64;  <code>chmod +x alpine-spotify-installer.sh</code>. Then, run <code>sudo arch-chroot root.x86_64</code>.  Then, run <code>./alpine-spotify-installer.sh</code>.
 
 
{{Cat|alpine-spotify-installer.sh|<nowiki>
 
# Copyright (c) 2018 Orson Teodoro <orsonteodoro@hotmail.com>
 
#
 
# Permission is hereby granted, free of charge, to any person obtaining a copy
 
# of this software and associated documentation files (the "Software"), to deal
 
# in the Software without restriction, including without limitation the rights
 
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 
# copies of the Software, and to permit persons to whom the Software is
 
# furnished to do so, subject to the following conditions:
 
#
 
# The above copyright notice and this permission notice shall be included in all
 
# copies or substantial portions of the Software.
 
#
 
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 
# SOFTWARE.
 
 
pacman --noconfirm -Syu
 
 
pacman --noconfirm -S base-devel
 
pacman --noconfirm -S xorg-server
 
pacman --noconfirm -S shadow
 
pacman --noconfirm -S sudo
 
pacman --noconfirm -S git
 
 
chmod 0660 /etc/sudoers
 
sed -i -e 's|# %wheel ALL=(ALL) NOPASSWD: ALL|%wheel ALL=(ALL) NOPASSWD: ALL\nspotify ALL=(ALL:ALL) NOPASSWD:ALL\n|g' /etc/sudoers || return 1
 
chmod 0440 /etc/sudoers
 
 
echo "Creating user spotify"
 
useradd -m spotify
 
echo "Deleting password for spotify"
 
passwd -d spotify
 
 
gpasswd -a spotify users
 
gpasswd -a spotify audio
 
gpasswd -a spotify video
 
gpasswd -a spotify wheel
 
 
echo "switching to spotify nix account"
 
su spotify
 
 
cd /home/spotify
 
mkdir aur
 
cd aur
 
 
cd /home/spotify/aur
 
git clone https://aur.archlinux.org/spotify.git
 
cd /home/spotify/aur/spotify
 
sudo -u spotify makepkg --noconfirm -si
 
 
cd /home/spotify/aur/
 
git clone https://aur.archlinux.org/paxctl.git
 
cd /home/spotify/aur/paxctl
 
sudo -u spotify makepkg --noconfirm -si
 
 
#for grsecurity kernels like Alpine
 
sudo paxctl -C /usr/share/spotify/spotify
 
sudo paxctl -z /usr/share/spotify/spotify
 
sudo paxctl -m /usr/share/spotify/spotify
 
 
sudo pacman --noconfirm -S alsa-lib
 
 
sudo pacman --noconfirm -S alsa-utils
 
 
#confirm that the sound card(s) shows up
 
sudo aplay -l
 
 
sudo spotify
 
</nowiki>
 
}}
 
 
To make this easier, create a launcher script:
 
 
{{Cat|run.sh|<nowiki>!/bin/bash
 
DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
 
cd $DIR
 
sudo arch-chroot -u spotify root.x86_64 /bin/sh -c "sudo spotify"
 
</nowiki>
 
}}
 
 
If it shows <code>(spotify:4): Gtk-WARNING **: cannot open display: :0.0</code> Before running Spotify try:
 
 
  xhost +local:
 
 
You could insert it at the very top in the above wrapper script.
 
 
You may want to look at [https://github.com/orsonteodoro/docker-arch-spotify-PaXmarked/blob/master/deflate.sh this script] to learn how to lock it down by removing the unnecessary cruft in your chroot collections that may be abused.
 
  
 
[[Category:Development]]
 
[[Category:Development]]
 
[[Category:Installation]]
 
[[Category:Installation]]

Latest revision as of 12:32, 5 April 2021

If you want to run glibc programs in Alpine Linux, there are a few ways of doing so. You could install glibc as additional to musl (you would have to do this manually), or you could do it the easy way and use either Flatpak (the easiest) or a chroot.

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


Your options

Flatpak

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

sudo apk add flatpak

Then you can run any Flatpak application:

flatpak run <flatpak name>

It is recommended to enable Flathub using it's 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

Gentoo Linux

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

First,

sudo apk add xz

Enter the chroot:

mkdir ~/chroot
cd ~/chroot
tar -xvf stage3-*.tar.xz
tar -xvf portage-latest.tar.xz
mv portage usr
sudo mount --bind /dev dev
sudo mount --bind /sys sys
sudo mount -t proc proc proc
cp /etc/resolv.conf etc
sudo 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 || sudo mount --bind /dev dev mount | grep $CHROOT_PATH/sys || sudo mount --bind /sys sys mount | grep $CHROOT_PATH/proc || sudo mount -t proc proc proc cp /etc/resolv.conf etc sudo chroot --userspec=$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:

 sudo apk add arch-install-scripts
 mkdir ~/chroot && cd ~/chroot
 curl -O https://mirrors.edge.kernel.org/archlinux/iso/latest/archlinux-bootstrap-2021.04.01-x86_64.tar.gz
 sudo tar xzf archlinux-bootstrap-2021.04.01-x86_64.tar.gz && rm archlinux-bootstrap-2021.04.01-x86_64.tar.gz
 sudo sed -i '/evowise/s/^#//' root.x86_64/etc/pacman.d/mirrorlist
 sudo sed -i '/CheckSpace/s/^/#/' root.x86_64/etc/pacman.conf
 sudo 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

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 http://http.debian.net/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.