change shell for any user to use /bin/bash

changeshell.sh

#!/usr/bin/expect -f

###
# 
# Copyright (c) 2013 KimSia Sim
# 
# Ubuntu 12.10 based change shell for users
# Run this by executing the following from a fresh install of Ubuntu 12.10 server:
# 
#     expect -c "$(curl -fsSL https://raw.github.com/gist/5126919)" <username> <password>
# 
# Be sure to replace <username> with your intended username and <password> with your intended password.
# Also, run this as root, unless you enjoy failing.
# Be sure you have installed expect. Run apt-get install expect before this.
# 
# Its handy to install 'screen' if you want to ensure your remote connection to
# a server doesn't disrupt the installation process. If you want to do this, just
# do the following before running the main bash command:
# 
#     apt-get install screen -y
#     screen
# 
# To recover your session if you are disconnected, ssh to your server as root again,
# and type:
# 
#     screen -x
# 
# Dependencies:
# - curl
# 
# Todo:
# - SSL Configuration
# 
###
 

 
set CHANGESHELL_FOR_USER [lindex $argv 0];
set PASSWORD_OF_USER [lindex $argv 1];
 
########################################
## switch to another user
## read this http://stackoverflow.com/a/1988255/80353
########################################
sudo -u $CHANGESHELL_FOR_USER -H sh -c "chsh -s /bin/bash" 

expect "*?assword:*" {send -- "$PASSWORD_OF_USER\r";}
expect eof