Re: [gentoo-user] Screen: Cannot open your terminal '/dev/tty1' - please check [Update]

[German <gentgerman@gmail.com>]

On Tue, 17 Mar 2015 22:14:03 +0200
Matti Nykyri <matti.nykyri@iki.fi> wrote:

> > On Mar 17, 2015, at 21:52, German <gentgerman@gmail.com> wrote:
> > 
> > On Tue, 17 Mar 2015 20:39:46 +0200
> > Matti Nykyri <matti.nykyri@iki.fi> wrote:
> > 
> >>> On Mar 17, 2015, at 19:33, German <gentgerman@gmail.com> wrote:
> >>> 
> >>> On Tue, 17 Mar 2015 19:16:42 +0200
> >>> Matti Nykyri <matti.nykyri@iki.fi> wrote:
> >>> 
> >>>>>> On Mar 17, 2015, at 18:11, German <gentgerman@gmail.com> wrote:
> >>>>>> 
> >>>>>> Don't hit your head to a brick wall. A small strace to the login process reveals that login set things as you tell it to in /etc/login.defs
> >>>>>> 
> >>>>>> In this file change the line:
> >>>>>> TTYPERM 0600
> >>>>>> To:
> >>>>>> TTYPERM 0620
> >>>>>> 
> >>>>>> And your problem is fixed.
> >>>>> 
> >>>>> Sorry, this didn't fix it
> >>>> 
> >>>> Yes. Sorry. The mode was wrong:
> >>>> 
> >>>> TTYPERM 660
> >>>> 
> >>>> Will fix it, if your screen is setgid tty and ttyX is gid tty. If not then:
> >>>> 
> >>>> TTYPERM 666
> >>>> 
> >>>> Will fix it, but also your tty will be world readable. If you don't consider that too big security risk, then just go
> >>> 
> >>> Neither 660 nor 666 fixed it. Sorry :(
> >> 
> >> If you have:
> >> 
> >> TTYPERM 0666
> >> 
> >> And logout and login. What mode and ownership do you have in you tty (/dev/ttyX)?
> > 
> > Ok, Matti, 0666 worked, now I can run screen as a user. Thanks. Do you think I have to try to run it 0660? Will it be less security risk?
> 
> Well 0666 = 666. The reason it now worked is because you logged out and then back in. This is becaus login program only reads the /etc/login.defs-file when you login.
> 
I pretty much sure that I logged out and logged in back after setting to 666 and it didn't work, but setting to 0666 has worked. Strange.

> With mode 0666 every user on your computer can read everything (every character) you have in your screen (so not much privacy). If you set:
> 
> TTYGROUP utmp
> TTYPERM 0660
> 
> And have:
> 
> -rwxr-sr-x root utmp /usr/bin/screen
> 
> Everything will also work and you have more privacy.

I'll be the only user on this system. So I guess I can leave it as it is.

> 
> When /bin/login us run it changes ownership of the tty to the user who logs in. Su -l does not do this. That is why the screen doesn't work. ConsoleKit is the program that is responsible for many of these permission changes. Do you have that installed?

I think ConsoleKit was installed when I emerged screen, but I am not sure.
> 
> -- 
> -Matti
> 
> 
> 
> 


-- 
German <gentgerman@gmail.com>