#!/bin/bash
#
# .---.                  .              .
# |                      |              |
# |--- .--. .-.  .-.  .-.|  .-. .--.--. |.-.  .-. .--.  .-.
# |    |   (.-' (.-' (   | (   )|  |  | |   )(   )|  | (.-'
# '    '     --'  --'  -' -  -' '  '   -' -'   -' '   -  --'
#
#                    Freedom in the Cloud
#
# License
# =======
#
# Copyright (C) 2015-2016 Bob Mottram <bob@robotics.uk.to>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

PROJECT_NAME='freedombone'

export TEXTDOMAIN=${PROJECT_NAME}-client
export TEXTDOMAINDIR="/usr/share/locale"

CURR_USER=$USER
MESH_CLIENT_INSTALL=

# Version number of this script
VERSION="1.01"

# ssh (from https://stribika.github.io/2015/01/04/secure-secure-shell.html)
SSH_CIPHERS="chacha20-poly1305@openssh.com,aes256-gcm@openssh.com,aes128-gcm@openssh.com,aes256-ctr,aes192-ctr,aes128-ctr"
SSH_MACS="hmac-sha2-512-etm@openssh.com,hmac-sha2-256-etm@openssh.com,hmac-ripemd160-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-512,hmac-sha2-256,hmac-ripemd160,umac-128@openssh.com"
SSH_KEX="curve25519-sha256@libssh.org,diffie-hellman-group-exchange-sha256"
SSH_HOST_KEY_ALGORITHMS="ssh-ed25519-cert-v01@openssh.com,ssh-rsa-cert-v01@openssh.com,ssh-rsa-cert-v00@openssh.com,ssh-ed25519,ssh-rsa"

# see https://stribika.github.io/2015/01/04/secure-secure-shell.html
function ssh_remove_small_moduli {
	sudo awk '$5 > 2000' /etc/ssh/moduli > /home/$CURR_USER/moduli
	sudo mv /home/$CURR_USER/moduli /etc/ssh/moduli
}

function configure_ssh_client {
	#sudo sed -i 's/#   PasswordAuthentication.*/   PasswordAuthentication no/g' /etc/ssh/ssh_config
	#sudo sed -i 's/#   ChallengeResponseAuthentication.*/   ChallengeResponseAuthentication no/g' /etc/ssh/ssh_config
	sudo sed -i "s/#   HostKeyAlgorithms.*/   HostKeyAlgorithms $SSH_HOST_KEY_ALGORITHMS/g" /etc/ssh/ssh_config
	sudo sed -i "s/#   Ciphers.*/   Ciphers $SSH_CIPHERS/g" /etc/ssh/ssh_config
	sudo sed -i "s/#   MACs.*/   MACs $SSH_MACS/g" /etc/ssh/ssh_config
	if ! grep -q "HostKeyAlgorithms" /etc/ssh/ssh_config; then
		sudo cp /etc/ssh/ssh_config ~/ssh_config
		sudo chown $CURR_USER:$CURR_USER ~/ssh_config
		echo "   HostKeyAlgorithms $SSH_HOST_KEY_ALGORITHMS" >> ~/ssh_config
		sudo mv ~/ssh_config /etc/ssh/ssh_config
		sudo chown root:root /etc/ssh/ssh_config
	fi
	sudo sed -i "s/Ciphers.*/Ciphers $SSH_CIPHERS/g" /etc/ssh/ssh_config
	if ! grep -q "Ciphers " /etc/ssh/ssh_config; then
		sudo cp /etc/ssh/ssh_config ~/ssh_config
		sudo chown $CURR_USER:$CURR_USER ~/ssh_config
		echo "   Ciphers $SSH_CIPHERS" >> ~/ssh_config
		sudo mv ~/ssh_config /etc/ssh/ssh_config
		sudo chown root:root /etc/ssh/ssh_config
	fi
	sudo sed -i "s/MACs.*/MACs $SSH_MACS/g" /etc/ssh/ssh_config
	if ! grep -q "MACs " /etc/ssh/ssh_config; then
		sudo cp /etc/ssh/ssh_config ~/ssh_config
		sudo chown $CURR_USER:$CURR_USER ~/ssh_config
		echo "   MACs $SSH_MACS" >> ~/ssh_config
		sudo mv ~/ssh_config /etc/ssh/ssh_config
		sudo chown root:root /etc/ssh/ssh_config
	fi

	# Create ssh keys
	if [ ! -f /home/$CURR_USER/.ssh/id_ed25519 ]; then
		ssh-keygen -t ed25519 -o -a 100
	fi
	if [ ! -f /home/$CURR_USER/.ssh/id_rsa ]; then
		ssh-keygen -t rsa -b 4096 -o -a 100
	fi

	ssh_remove_small_moduli

	echo ''
	echo $'Copy the following into a file called /home/username/.ssh/authorized_keys on the Freedombone server'
	echo ''
	echo $(cat /home/$CURR_USER/.ssh/id_rsa.pub)
	echo $(cat /home/$CURR_USER/.ssh/id_ed25519.pub)
	echo ''
}

function configure_monkeysphere {
	sudo apt-get -y install monkeysphere
}

function show_help {
	echo ''
	echo $"${PROJECT_NAME}-client --mesh [yes|no]"
	echo ''
	exit 0
}

while [[ $# > 1 ]]
do
	key="$1"

	case $key in
		-h|--help)
			show_help
			;;
		--essid)
			shift
			WIFI_SSID="$1"
			;;
		--channel)
			shift
			WIFI_CHANNEL=${1}
			;;
		--mesh)
			shift
			MESH_CLIENT_INSTALL=${1}
			;;
		*)
			# unknown option
			;;
	esac
	shift
done

echo $'Configuring client'
configure_ssh_client
configure_monkeysphere
if [[ $MESH_CLIENT_INSTALL == $'yes' || $MESH_CLIENT_INSTALL == $'y' || $MESH_CLIENT_INSTALL == $'on' ]]; then
	${PROJECT_NAME}-mesh-install batman_client
	${PROJECT_NAME}-mesh-install babel_client
fi
echo $'Configuration complete'
exit 0