conf/157500: posible chsh bug on systems using nss_ldap/pam_ldap
ends adding users to /etc/master.passwd
Nicolas de Bari Embriz Garcia Rojas
nbari at sign.io
Wed Jun 1 15:40:09 UTC 2011
>Synopsis: posible chsh bug on systems using nss_ldap/pam_ldap ends adding users to /etc/master.passwd
>Arrival-Date: Wed Jun 01 15:40:09 UTC 2011
>Originator: Nicolas de Bari Embriz Garcia Rojas
FreeBSD sign.io 8.1-STABLE FreeBSD 8.1-STABLE #1: Sun Nov 21 16:09:52 CET 2010 root at sign.io:/usr/obj/usr/src/sys/SIGNIO amd64
I have a server using nss_ldap/pam_ldap (all users are stored on an ldap directory) but I notice that few users where available to change their shell using the command chsh -s /bin/sh.
In theory chsh like the passwd command should not operate on ldap and just work for local users.
in fact the passwd command output this:
passwd: Sorry, `passwd' can only change passwords for local or NIS users.
when creating an account via web (www.sign.io - info stored on ldap not localy and in a remote server) and after login for the first time to the server via ssh, the user can execute the command chsh -s /bin/sh and chsh will add the user to the /etc/passwd and /etc/master.passwd (this should not happen) but seems like chsh is ignoring nsswitch.conf:
group: files ldap
hosts: files dns
passwd: files ldap
if the user change his password (not using the passwd command) using an alternate script like this one:
read -p "Old Password: " oldp; echo
read -p "New Password: " np1; echo
read -p "Retype New Password: " np2; echo
if [ "$np1" != "$np2" ]; then
echo "Passwords do not match."
ldappasswd -h 172.16.13.1 -D uid="$USER",ou=people,dc=sign,dc=io\
-w "$oldp" \
-a "$oldp" \
The user can still login the the shell but if he want to change his shell again, he has to use his previous password since a new record on /etc/passwd and /etc/master.passwd has been created.
also the this new record does not respect the login.conf, since the entry looks like this:
where in theory they should have a hash beginning with $2 (since blf) is specified on the login.conf
the current login.conf is like this:
:path=/sbin /bin /usr/sbin /usr/bin /usr/games /usr/local/sbin /usr/local/bin ~/bin:\
create an account via ldap not locally (live example on www.sign.io)
login the the shell server that uses pam_ldap/nss_ldap (no local users on /etc/master.passwd) and execute the chsh -s /bin/sh.
chsh will ask for a password the one will be stored or used for creating a new entry on /etc/passwd (later update will update /etc/mater.passwd) (this should not happened)
unknown, maybe temporally disabling chsh
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