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Debian in chroot on Android

This works with Debian Jessie and does not work with Debian Stretch. APT HTTP method says that it cannot create socket, permission denied. Adding user to the inet/net_raw group does not help. It might be caused by the old 3.4 kernel.

Automated tool: Lil' Debi.

Uses fixed-size loopback device.
Requires free loopback device - does not work on CyanogenMod 11 on Nexus 4.

Manual installation:

Install with –foreign on a non-ARM computer

debootstrap --arch=armhf --foreign jessie armroot/ http://ftp.de.debian.org/debian
cp /usr/bin/qemu-arm-static armroot/usr/bin/
chroot armroot/
/debootstrap/debootstrap --second-stage

Transfer armroot/ to the device /data/armhf
First-time usage after reboot:

su -c "mount -t tmpfs -o context=u:object_r:fuse:s0 none /storage/emulated/legacy/DCIM/OpenCamera/foo"
su -c "mount -o bind /dev /data/armhf/dev; mkdir /data/armhf/system; mount -o bind /system /data/armhf/system; mkdir /data/armhf/aroot; mount -o bind / /data/armhf/aroot; export LD_PRELOAD=; export HOME=/root; export TERM=xterm; mount -o bind /mnt/shell/emulated/0/ /data/armhf/storage; chroot /data/armhf /bin/bash"

Unexporting LD_PRELOAD from the above example is needed on Android 5 and does not work on Android 6.
Next shell:

su -c "export LD_PRELOAD=; export HOME=/root; export TERM=xterm; chroot /data/armhf /bin/bash"

Useful .bashrc:

export PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/root/bin"

cd /root

/etc/init.d/ssh start >/dev/null  2>&1

mount | grep -q proc || mount -t proc none /proc
mount | grep -q devpts || (mount -t devpts none /dev/pts; mount -t sysfs none /sys)
export LANG=cs_cz.UTF-8
export LANGUAGE=cs_cz.UTF-8
[ -e /root/vault/pin ] || encfs /root/.vault /root/vault

My favorite terminal emulator: https://f-droid.org/repository/browse/?fdid=jackpal.androidterm