[Pkg-xfce-devel] Bug#661230: lightdm: passwordless login doesn't work

[Denys Gavrysh]

Hi,

I have set up lightdm to support guest accounts.
The problem lies in default PAM setting in Debian.

Here is the line that permits password-less logins on "secure" ttys in 
/etc/pam.d/common-auth file:
-----------------------------------------------------------------
auth	[success=1 default=ignore]	pam_unix.so nullok_secure
-----------------------------------------------------------------

We need just to allow blank password in any case.
What I actually done is:

# sed -e 's/_secure//' /etc/pam.d/common-auth > 
/etc/pam.d/common-auth-insecure
# sed -i -e 's/common-auth/&-insecure/' /etc/pam.d/lightdm

And it works, also preventing logins without password by SSH.
So, according to configured central authentication policy, lightdm 
(which is not a plain tty AFAIK) behavior seems correct.

-- 
Denys Gavrysh