How do I use the terminal SCREEN when chrooted?

Question

How do I allow a user to use SCREEN on a chrooted user?

I have tried everything but I keep on failing.

I need the user to be able to use SCREEN when they are logged in bash as a chrooted user.

The chrooted user must have enough access to open a new pty, also your question needs more info, do you use any extra security on your system (grsec, selinux, other)?

grawity · Answer 1 · 2012-10-12 20:09:14Z

up vote 2 down vote

SCREEN probably needs devpts, the pseudo-terminal filesystem, to be mounted on /dev/pts inside the chroot.

mount -t devpts none "$rootpath/dev/pts" -o ptmxmode=0666,newinstance

ln -fs "pts/ptmx" "$rootpath/dev/ptmx"

(The newinstance flag is optional; it gives the user a completely separate pty list, preventing them from knowing what other users are logged in.)

answered Oct 12 '12 at 20:09

grawity
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	Do I do that on the root user? – Muktadir Miah Oct 12 '12 at 20:16
	@MuktadirMiah: Yes, and you do that for every user's chroot. (You can automate it with `pam_exec`.) – grawity Oct 12 '12 at 20:32
	"I ran "mount -t devpts none "/home/jail/dev/pts" -o ptmxmode=0666,newinstance" I get the error "mount: mount point /home/jail/dev/pts does not exist" I used this tutorial to chroot the user: dharmitshah.blogspot.co.uk/2011/12/… – Muktadir Miah Oct 14 '12 at 17:06
	If the mountpoint does not exist, create it. With `mkdir`. – grawity Oct 14 '12 at 17:17
	I have done it but still I get "-su: screen: command not found" on the chrooted user. – Muktadir Miah Oct 14 '12 at 17:23

1 Answer