#!/bin/bash
#
# ********************************************************
#* Copyright (c) Scarlet Line 2010
#* Created on 2010-01-01 by Kevin Shepherd <code@scarletlne.com>
#* $URL$
#* $Id$
#**********************************************************/
#** \file ssh-pwd
#	\brief Script to securely remove the need to type ssh passwords.
#	
#	This script uses public/private key encryption to authorize the
#	local host to connect securely to the remote host via ssh.
#	Documented at: http://www.scarletline.com/howto/remove_ssh_password.html
#	filename: ssh-pwd
#
LOCALUSER=$USER	# - your user name at the local computer
LOCALHOST=$HOSTNAME	# - the host name of your local computer
REMOTEHOST=$1	# - the host name of the remote computer
REMOTEUSER=$LOCALUSER	# - the user name that you connect to the remote computer as
# REMOTEPASS	# - the remote user's password on the remote system

if [ "$REMOTEHOST" == "" ]
	then
	echo "Usage: ssh-pwd <remote-host> [<remote-user>]"
	exit 1
fi

if [ "$2" != "" ]
	then
	REMOTEUSER=$2
fi

echo "LOCALUSER=$LOCALUSER	- your user name at the local computer";
echo "LOCALHOST=$LOCALHOST	- the host name of your local computer";
echo "REMOTEUSER=$REMOTEUSER	- the user name as whom you connect to the remote computer";
echo "REMOTEHOST=$REMOTEHOST	- the host name of the remote computer";
echo "$LOCALUSER@$LOCALHOST --> $REMOTEUSER@$REMOTEHOST"

# Set Up Your Local System Once
if [ ! -f ~/.ssh/id_rsa.pub ]
	then
	echo "Setting up your local system keys ..."
	echo "   ssh-keygen -t rsa -N \"\" -C \"Automatically generated by ssh-pwd\" -f ~/.ssh/id_rsa"
	ssh-keygen -t rsa -N "" -C "Automatically generated by ssh-pwd" -f ~/.ssh/id_rsa
	# Generating public/private rsa key pair.
	# Enter file in which to save the key (/home/<local-user>/.ssh/id_rsa):
	# Enter passphrase (empty for no passphrase):
	# Enter same passphrase again:
	# Your identification has been saved in /home/<local-user>/.ssh/id_rsa.
	# Your public key has been saved in /home/<local-user>/.ssh/id_rsa.pub.
	# The key fingerprint is:
	# 62:a5:fc:a4:b0:d8:87:f0:98:28:17:d4:e3:8e:aa:2f <local-user>@<local-host>
	echo "   ls -l ~/.ssh"
	ls -l ~/.ssh
	# id_rsa id_rsa.pub known_hosts
	else
	echo "Keys already exist in ~/.ssh"
	echo "   ls -l ~/.ssh"
	ls -l ~/.ssh
fi

# Set Up The Remote Host 
echo "Setting up remote host ..."
echo "   scp -o StrictHostKeyChecking=no ~/.ssh/id_rsa.pub $REMOTEUSER@$REMOTEHOST:$LOCALHOST.ssh"
echo "   *** When asked for a password, enter that of $REMOTEUSER@$REMOTEHOST ***"
scp -o StrictHostKeyChecking=no ~/.ssh/id_rsa.pub $REMOTEUSER@$REMOTEHOST:$LOCALHOST.ssh
# <remote-user>@<remote-host>'s password:<remote-pass>
# id_rsa.pub                                     100%  227   824.0KB/s   00:00
echo "   ssh -o StrictHostKeyChecking=no $REMOTEUSER@$REMOTEHOST \"if [ ! -d ~/.ssh ]; then mkdir ~/.ssh; fi; if [ -f ~/.ssh/authorized_keys ]; then cat ~/$LOCALHOST.ssh >> ~/.ssh/authorized_keys; else cp ~/$LOCALHOST.ssh ~/.ssh/authorized_keys; fi; chmod 644 ~/.ssh/authorized_keys;ls -l ~/.ssh\""
echo "   *** When asked for a password, enter that of $REMOTEUSER@$REMOTEHOST ***"
ssh -o StrictHostKeyChecking=no $REMOTEUSER@$REMOTEHOST "if [ ! -d ~/.ssh ]; then mkdir ~/.ssh; fi; if [ -f ~/.ssh/authorized_keys ]; then cat ~/$LOCALHOST.ssh >> ~/.ssh/authorized_keys; else cp ~/$LOCALHOST.ssh ~/.ssh/authorized_keys; fi; chmod 644 ~/.ssh/authorized_keys;ls -l ~/.ssh"
# <remote-user>@<remote-host>'s password:<remote-pass>
# cat ~/$LOCALHOST.ssh >> ~/.ssh/authorized_keys
# chmod 644 ~/.ssh/authorized_keys
# ls -l ~/.ssh
# total 8
# -rw-r--r--    1 <remote-user>     <remote-group>          227 Feb 23 14:27 authorized_keys
# -rw-r--r--    1 <remote-user>     <remote-group>          222 Dec 13 02:13 known_hosts
# exit
# Connection to <remote-host> closed.
echo "Test automatic connection (worked if there are no complaints) ..."
echo "   ssh -v $REMOTEUSER@$REMOTEHOST exit"
ssh -v $REMOTEUSER@$REMOTEHOST exit
# Last login: Thu Feb 23 14:26:00 2006 from 192.168.1.67
# Access to, or unauthorized use of data on this computer by any person other
# than authorized employee(s) or owner(s) of an account is strictly prohibited
# and may result in legal action against such person.