#!/bin/bash

. /usr/sbin/so-common

if [[ $1 =~ ^(-q|--quiet) ]]; then
	quiet=true
fi

before=
after=
reload_required=false

print_sshd_t() {
	local string=$1
	local state=$2
	echo "${state}:"

	local grep_out
	grep_out=$(sshd -T | grep "^${string}")

	if [[ $state == "Before" ]]; then
		before=$grep_out
	else
		after=$grep_out
	fi

	echo $grep_out
}

print_msg() {
	local msg=$1
	if ! [[ $quiet ]]; then
	printf "%s\n" \
		"----" \
		"$msg" \
		"----" \
		""
	fi
}

if ! [[ $quiet ]]; then print_sshd_t "ciphers" "Before"; fi
sshd -T | grep "^ciphers" | sed -e "s/\(3des-cbc\|aes128-cbc\|aes192-cbc\|aes256-cbc\|arcfour\|arcfour128\|arcfour256\|blowfish-cbc\|cast128-cbc\|rijndael-cbc@lysator.liu.se\)\,\?//g" >> /etc/ssh/sshd_config
if ! [[ $quiet ]]; then
	print_sshd_t "ciphers" "After"
	echo ""
fi

if [[ $before != $after ]]; then
	reload_required=true
fi

if ! [[ $quiet ]]; then print_sshd_t "kexalgorithms" "Before"; fi
sshd -T | grep "^kexalgorithms" | sed -e "s/\(diffie-hellman-group14-sha1\|ecdh-sha2-nistp256\|diffie-hellman-group-exchange-sha256\|diffie-hellman-group1-sha1\|diffie-hellman-group-exchange-sha1\|ecdh-sha2-nistp521\|ecdh-sha2-nistp384\)\,\?//g" >> /etc/ssh/sshd_config
if ! [[ $quiet ]]; then
	print_sshd_t "kexalgorithms" "After"
	echo ""
fi

if [[ $before != $after ]]; then
	reload_required=true
fi

if ! [[ $quiet ]]; then print_sshd_t "macs" "Before"; fi
sshd -T | grep "^macs" | sed -e "s/\(hmac-sha2-512,\|umac-128@openssh.com,\|hmac-sha2-256,\|umac-64@openssh.com,\|hmac-sha1,\|hmac-sha1-etm@openssh.com,\|umac-64-etm@openssh.com,\|hmac-sha1\)//g" >> /etc/ssh/sshd_config
if ! [[ $quiet ]]; then
	print_sshd_t "macs" "After"
	echo ""
fi

if [[ $before != $after ]]; then
	reload_required=true
fi

if ! [[ $quiet ]]; then print_sshd_t "hostkeyalgorithms" "Before"; fi
sshd -T | grep "^hostkeyalgorithms" | sed "s|ecdsa-sha2-nistp256,||g" | sed "s|ssh-rsa,||g" >> /etc/ssh/sshd_config
if ! [[ $quiet ]]; then
	print_sshd_t "hostkeyalgorithms" "After"
	echo ""
fi

if [[ $before != $after ]]; then
	reload_required=true
fi

if [[ $reload_required == true ]]; then
	print_msg "Reloading sshd to load config changes..."
	systemctl reload sshd
fi

{% if grains['os'] != 'CentOS' %}
print_msg "[ WARNING ] Any new ssh sessions will need to remove and reaccept the ECDSA key for this server before reconnecting."
{% endif %}