Howto HostAuth

What is this?

This is PAM host-auth module for linux-vserver powered systems.

The nss_vserver module allows processes running on the host (sshd, getty) to authenticate users that exist on guests.

If you want to complete the guest login process, you should also get a modified version of vslogin linked to below. vslogin will pick up after authentication and deliver the user to a shell on his guest.

Note that with nss_vserver you don't need the syncshadows included in the vserverauth tarball.

Installation Instructions

On linux, just run

make install

After, try to run

make test

To see if it works.

How to remove it from system?

Just run

make uninstall

Use with vslogin

After you have installed module, (and have vslogin copied to /sbin/ and suid-root) you are ready: try to login into a guest, say one named "test" with user "user", by loggin in into the host with username "test-user" or "user@test." You should find yourself logged into the guest.

Caveats

Security

WARNING! If you have installed vslogin, NEVER give shell access to your host to users -- any user on host, who able to execute programs and modify environment will be able to log into guests as anybody he wants!

Usernames and guest names with dashes

Avoid using usernames or guest names with dashes.

The current version only tries one configuration while searching for the user in guest databases, which can cause problems:

• User "user" on guest "ser-ver" when written as "user@ser-ver" will work fine, while "ser-ver-user" will be threated as user "ver-user" on vserver "ser".
• User "us-er" on guest "server" when written as "guest-us-er" will work fine, while "us-er@guest" will be threated as user "er@guest" on vserver "us".

If you must have dashes, use the syncshadows method instead.

Download links

nss_vserver: http://dev.call2ru.com/vs/nss_vserver.tar.bz2

modified vslogin: http://dev.call2ru.com/vs/vserverauth.tar.gz

Authors and copyright

nss_vserver was written by Anton Fedorov <datacompboy@call2ru.com> 19 march 2006 and is public domain; feel free to use it as you want.

vslogin was written by Alec Thomas (http://swapoff.org/LinuxVServer)