[UPD] 2018-12-01

It's a Docker time :)

Just use command

docker run -d --restart always --name intheshell -p 22:22222 es1n/intheshell

to run latest Docker image, boo! 👻

Don't forget, that image will bind 22 port (ssh), so change your host machine port to something else, 2222 for example

[Deprecated] Installation instruction

Upload intheshell into /usr/local/bin/

Create user ghost

useradd -m -s /usr/local/bin/intheshell ghost

Remove password for ghost

sed -ri s/ghost:(!)?:/ghost:U6aMy0wojraho:/g /etc/shadow

Allow empty password in sshd and add allowed users (file /etc/ssh/sshd_config) and some security changes

..........
PermitEmptyPasswords yes
PasswordAuthentication yes
..........
AllowUsers ghost

### Disable Subsystem
#Subsystem sftp /usr/lib/openssh/sftp-server
### X11 Forwarding
X11Forwarding no

# Adding chroot
Match User ghost
    ChrootDirectory /chroot/ghost
    AllowTcpForwarding no
..........

Adding chroot for user ghost

dir=/chroot/ghost
mkdir -p $dir
mkdir -p $dir/{dev,lib64,lib,bin,etc}
mkdir -p $dir/usr/local/bin
mknod -m 666 $dir/dev/null c 1 3
mknod -m 666 $dir/dev/tty c 5 0
mknod -m 666 $dir/dev/zero c 1 5
mknod -m 666 $dir/dev/random c 1 8
chown root:root $dir
chmod 0755 $dir
mkdir -p $dir/lib/x86_64-linux-gnu/
cp -v /lib/x86_64-linux-gnu/{libncurses.so.5,libtinfo.so.5,libdl.so.2,libc.so.6} $dir/lib/
cp -v /lib64/ld-linux-x86-64.so.2 $dir/lib64/
cat /etc/passwd | grep ghost > $dir/etc/passwd
touch $dir/etc/group
cp -av /bin/stty $dir/bin
cp -av /usr/local/bin/intheshell $dir/bin
cp -av /usr/local/bin/intheshell $dir/usr/local/bin

Disable motd and other stuff on ssh login (not so beautyfull)

chmod -x /etc/update-motd.d/*

Then restart sshd

/etc/init.d/ssh restart