Provisions the Debian Host to allow for SSH from Github user public key

provision_deploy_env.sh

#!/bin/bash

#=================================================================================================#
#provision_deploy_env.sh
#----------
#by: ilobmirt @ 2023_JUL_07
#
#Sets up this node
#=================================================================================================#

function include_git_libs(){
	local git_user="$1"
	local git_lib_id="$2"
	#If either is blank because it wasn't inputted, include my own
	if [ ${#git_user} -eq 0 ] || [ ${#git_lib_id} -eq 0 ]; then
		git_user='ilobmirt'
		git_lib_id='4852e33aaf0fbb064c2a3b6141ed5172'
	fi
	local lib_dir="/tmp/gists/${git_user}"
	local lib_file="shared_functs_${git_lib_id}.lib"
	local lib_source="https://gist.githubusercontent.com/${git_user}/${git_lib_id}/raw"
	if [ ! -d "${lib_dir}" ]; then
		mkdir -p $lib_dir
	fi
	if [ ! -f "${lib_dir}/${lib_file}" ]; then
		wget -q --output-document="${lib_dir}/${lib_file}" $lib_source
	fi
	source "${lib_dir}/${lib_file}"
}

function nm_set(){
	#EXAMPLES:
	#	nm_set eth0 192.168.1.69/24 1.1.1.1,1.0.0.1
	#	nm_set eth0 dhcp
	#	nm_set eth0 del
	local target_dev="$1"
	local target_state="$2"
	local target_dns="$3"
	#Do nothing if device and state is not defined
	if [ ${#target_dev} -eq 0 ] || [ ${#target_state} ] ; then
		return
	fi
	local connection_exists=$(nmcli con | grep "autoconfig-${target_dev}")
	#If we just wanna delete the connection, lets be done with it
	if [ ${#connection_exists} -gt 0 ] && [[ "${target_state}"=='del' ]] ; then
		sudo nmcli con del "autoconfig-${target_dev}"
		return
	fi
	#create the connection if it did not exist
	local target_type=''
	case "${target_dev:0:3}" in
		'eth' | 'enp')
			target_type='ethernet'
			;;
		'wla' | 'wlp')
			target_type='wifi'
			;;
		*)
			;;
	esac
	if [ ${#connection_exists} -eq 0 ] ; then
		sudo nmcli con add type "${target_type}" ifname "${target_interface}" con-name "${static_interface}"
	fi
	#Our target states are up / down / dhcp / (some ipv4 address)
	case "${target_state}" in
		'up')
			sudo nmcli con up "autoconfig-${target_dev}"
			;;
		'down')
			sudo nmcli con down "autoconfig-${target_dev}"
			;;
		'dhcp')
			sudo nmcli con mod "autoconfig-${target_dev}" ipv4.method auto
			sudo nmcli con mod "autoconfig-${target_dev}" ipv6.method disabled
			sudo nmcli con up "autoconfig-${target_dev}"
			;;
		*)
			sudo nmcli con mod "autoconfig-${target_dev}" ipv4.method manual ipv4.addr "${target_state}"
			if [ ${#target_dns} -gt 0 ] ; then
				sudo nmcli con mod "autoconfig-${target_dev}" ipv4.dns "${target_dns}"
			fi
			sudo nmcli con up "autoconfig-${target_dev}"
			;;
	esac
}

main(){

	#Install network Manager if not already installed
        if [[ "$(which nmcli)" == '' ]]; then
                echo "NMCLI not installed, installing"
                sudo apt update
                sudo apt-get install network-manager -y
                echo "Granting control to nmcli by cleaning up network interfaces"
                sudo mv -f /etc/network/interfaces /etc/network/interfaces.old
                sudo touch /etc/network/interfaces
                sudo systemctl restart NetworkManager
        fi

	local eth_dev=$(nmcli dev | sed -r 's/\s/###/g;s/###.*//g;/^(eth|enp)/!d;1,1! d')
	nm_set "${eth_dev}" dhcp
	include_git_libs

	local func_input="$(l2s "$@")"
	local target_user=''
	local target_hostname=''
	local target_git_sources=''

	fill_params --input "${func_input}" --var target_user --search user --default 'example_user' > /dev/null
	fill_params --input "${func_input}" --var target_hostname --search hostname --default 'example_host' > /dev/null
	fill_params --input "${func_input}" --var target_git_sources --search git --default 'ilobmirt' > /dev/null

	#We split the git sources list by comma (no spaces)
	#target_git_sources=$(echo "${target_git_sources}" | readarray -d ',')
	readarray -t target_git_sources <<< $(echo "${target_git_sources}" | sed 's/,/\n/g')
	
	local out_txt=$(cat <<EOF
╔═════════════════════════════╗
║We have passed the following:║
╚═════════════════════════════╝
    ▻ USERNAME: ${target_user}
       ▔▔▔▔▔▔▔▔▔
    ▻ HOSTNAME: ${target_hostname}
       ▔▔▔▔▔▔▔▔▔
    ▻ GIT KEY SOURCES:
       ▔▔▔ ▔▔▔ ▔▔▔▔▔▔▔▔
$(printf "\t[%s]\n" "${target_git_sources[@]}")
EOF
)

	printf "%s\n\n\n" "${out_txt}"

	#PREREQ - CURL + OPENSSH-SERVER
	printf "\tSTEP 1> SETUP PREREQ PACKAGES\n\n"
	setup_packages curl openssh-server > /dev/null

	#Set our desired hostname
	printf "\tSTEP 2> SETUP HOSTNAME\n\n"
	set_hostname ${target_hostname} > /dev/null
	
	#Establish github keys from the following people
	printf "\tSTEP 3> ADD GITHUB PUBLIC KEYS\n"
	for input_git_user in "${target_git_sources[@]}" ; do
		printf "\t\t> ${input_git_user}\n"
		github_ssh_key --user "${target_user}" --github "${input_git_user}" --method 'add' > /dev/null
	done
	printf "\n\n"

	out_txt=$(cat <<EOF
╔══════════════╗
║End of Script:║
╚══════════════╝
    The host \"$(hostname)\" has been set up for the user \"${target_user}\"
    It should now be accessible over ssh using the github keys
EOF
)

  printf "%s\n\n\n" "${out_txt}"
	
}

main $@