#!/bin/bash
################################################################################
# Intended use: Simple shell script to create certs (RSA or EC)
#
# Notes: This script support Linux Bash shell script only
# Install Bash from https://www.gnu.org/software/bash/
#
# Copyright (C) 2015 - 2025, VGISC Dev Team <dev@vgisc.com>
################################################################################

filepath=`readlink -f $0`
basedir=`dirname $filepath`

SCRIPT_DIR=`dirname $filepath`
FLAG_EC=0
COMMON_ARGS="-batch"
DOMAIN="vgisc.com"

OPENSSL_BIN="$basedir/bin/openssl"

init_dir(){
	if [ -f "$basedir/root-ca" ]; then
		return
	fi

	mkdir -p $basedir/{root-ca,sub-ca}/{db,certs,private}

	touch $basedir/{root-ca,sub-ca}/db/index
	touch $basedir/{root-ca,sub-ca}/db/index.attr
	chmod 700 $basedir/{root-ca,sub-ca}/private
	$OPENSSL_BIN rand -hex 16 > $basedir/root-ca/db/serial
	$OPENSSL_BIN rand -hex 16 > $basedir/sub-ca/db/serial
	echo 1001 > $basedir/root-ca/db/crlnumber
	echo 1001 > $basedir/sub-ca/db/crlnumber

	cp $basedir/conf/root-ca.conf $basedir/root-ca/root-ca.conf
	cp $basedir/conf/sub-ca.conf $basedir/sub-ca/sub-ca.conf
}

gen_ca()
{
	if [ -f "$basedir/root-ca/root-ca.crt" ];then
		echo "Root CA is present, please delete it or run build.sh clean before generate a new root CA"
		return
	fi

	init_dir

	cd $basedir/root-ca

	if [ $FLAG_EC -eq 0 ];then
		$OPENSSL_BIN req -new -config root-ca.conf -out root-ca.csr -keyout private/root-ca.key -nodes
		$OPENSSL_BIN rsa -in private/root-ca.key -out private/root-ca.key

	else
		$OPENSSL_BIN ecparam -genkey -name secv384 -out private/root-ca.key
		$OPENSSL_BIN req -new -config root-ca.conf -key private/root-ca.key -out root-ca.csr
		$OPENSSL_BIN ec -in private/root-ca.key -out private/root-ca.key
	fi

	$OPENSSL_BIN ca $COMMON_ARGS -selfsign -config root-ca.conf -rand_serial\
		-in root-ca.csr -out root-ca.crt\
		-extensions ca_ext
}

gen_subca()
{
	if [ -f "$basedir/sub-ca/sub-ca.crt" ];then
		echo "Sub CA is present, please delete it or run build.sh clean before generate a new sub CA"
		return
	fi

	if [ ! -f "$basedir/root-ca/root-ca.crt" ];then
		echo "Root CA not present...  Building CA now..."
		gen_ca
	fi

	cd $basedir/sub-ca

	if [ $FLAG_EC -eq 0 ]; then
		$OPENSSL_BIN req -new -config sub-ca.conf -nodes\
			-out sub-ca.csr -keyout private/sub-ca.key
	else
		$OPENSSL_BIN ecparam -genkey -name secv384 -out private/sub-ca.key
		$OPENSSL_BIN req -new -config sub-ca.conf -key private/sub-ca.key -out sub-ca.csr
	fi

	cd $basedir/root-ca
	$OPENSSL_BIN ca $COMMON_ARGS -config root-ca.conf -rand_serial\
		-in $basedir/sub-ca/sub-ca.csr -out $basedir/sub-ca/sub-ca.crt\
		-extensions sub_ca_ext
}

server()
{
	if [ ! -f "$basedir/sub-ca/sub-ca.crt" ];then
		echo "Sub CA not present...  Building Sub CA now..."
		gen_subca
		
	fi

	mkdir -p $basedir/server
	cp $basedir/conf/openssl.cnf $basedir/server/
	cd $basedir/server

	CN=$1

	if [ $FLAG_EC -eq 0 ]; then
		$OPENSSL_BIN req -config openssl.cnf -new -nodes\
			-out "$CN.csr" -keyout "$CN.key"\
			-subj "/C=VN/ST=Ha Noi/L=Dong Da/O=VGISC/CN=$CN"\
			-addext "subjectAltName=DNS:$CN,DNS:*.$CN"
	else
		$OPENSSL_BIN ecparam -genkey -name secv384 -out "$CN.key"
		$OPENSSL_BIN req -config openssl.cnf -new\
			-key "$CN.key" -out "$CN.csr"\
			-subj "/C=VN/ST=Ha Noi/L=Dong Da/O=VGISC/CN=$CN"\
			-addext "subjectAltName=DNS:$CN,DNS:*.$CN"
	fi

	cd $basedir/sub-ca
	$OPENSSL_BIN ca $COMMON_ARGS -config sub-ca.conf -rand_serial\
		-in $basedir/server/$CN.csr -out $basedir/server/$CN.crt\
		-extensions server_ext
	
	cat sub-ca.crt >> $basedir/server/$CN.crt
}

client()
{
	if [ ! -f "$basedir/sub-ca/sub-ca.crt" ];then
		echo "Sub CA not present...  Building Sub CA now..."
		gen_subca
	fi

	mkdir -p $basedir/client
	cp $basedir/conf/openssl.cnf $basedir/client/
	cd $basedir/client

	CN=$1
	if [ $FLAG_EC -eq 0 ]; then
		$OPENSSL_BIN req -config openssl.cnf -new -nodes\
			-out "$CN.csr" -keyout "$CN.key"\
			-subj "/C=VN/ST=Ha Noi/L=Dong Da/O=VGISC/CN=$CN"
	else
		$OPENSSL_BIN ecparam -genkey -name secv384 -out "$CN.key"
		$OPENSSL_BIN req -config openssl.cnf -new\
			-out "$CN.csr" -key "$CN.key"\
			-subj "/C=VN/ST=Ha Noi/L=Dong Da/O=VGISC/CN=$CN"
	fi

	cd $basedir/sub-ca
	$OPENSSL_BIN ca $COMMON_ARGS -config sub-ca.conf -rand_serial\
		-in $basedir/client/$CN.csr -out $basedir/client/$CN.crt\
		-extensions client_ext
	cat sub-ca.crt >> $basedir/client/$CN.crt

}

test_server()
{
	server test.com
	cd $basedir
	# Both the s_server and s_client won't send the full chain, 
	# which differs from what the Web Server and Browser do.
	# So we have to concatenate the CA and SubCA as a whole
	cat sub-ca/sub-ca.crt root-ca/root-ca.crt > /tmp/ca-bundle.crt

	if [ $FLAG_EC -eq 0 ]; then
		$OPENSSL_BIN s_server -accept 8443 -verify 2 -state\
			-CAfile /tmp/ca-bundle.crt\
			-cert server/test.com.crt\
			-key server/test.com.key
	else
		$TEST_OPENSSL_BIN s_server -accept 8443 -verify 2 -state\
			-CAfile /tmp/ca-bundle.crt\
			-cert server/test.com.crt\
			-key server/test.com.key
	fi

}

test_client()
{
	client UserTest
	cd $basedir

	if [ $FLAG_EC -eq 0 ]; then
		$OPENSSL_BIN s_client -connect 127.0.0.1:8443\
			-verify 2 -state\
			-CAfile root-ca/root-ca.crt\
			-cert client/UserTest.crt\
			-key client/UserTest.key
	else
		$TEST_OPENSSL_BIN s_client -connect 127.0.0.1:8443\
			-config $basedir/client/openssl.cnf\
			-verify 2 -state\
			-CAfile root-ca/root-ca.crt\
			-cert client/UserTest.crt\
			-key client/UserTest.key
	fi

}

verify()
{
	cd $basedir
	for i in `ls server/*.crt client/*.crt`;
	do
		echo 
		$OPENSSL_BIN verify -show_chain\
			-CAfile root-ca/root-ca.crt -untrusted sub-ca/sub-ca.crt $i
	done

}

clean()
{
	rm -rf $basedir/root-ca
	rm -rf $basedir/sub-ca
	rm -rf $basedir/server
	rm -rf $basedir/client
	rm -rf $basedir/ca.crt
}

usage()
{
	echo "================================"
	echo "Usage:"
	echo " ./build.sh rsa/ec gen_ca                 # generate CA keys and certs"
	echo " ./build.sh rsa/ec gen_subca              # generate Sub CA keys and certs (implying: gen_ca)"
	echo " ./build.sh rsa/ec server wwww.vgisc.com  # generate Server certs with CommonName: www.test.com (implying: gen_subca)"
	echo " ./build.sh rsa/ec client vpn1.vgisc.com  # generate client certs with CommonName: Client1 (implying: gen_subca)"
	echo ""
	echo " ./build.sh rsa/ec test_server            # generate a test server cert and run openssl s_server on 127.0.0.1:8443"
	echo " ./build.sh rsa/ec test_client            # generate a test client cert and run openssl s_client connecting 127.0.0.1:8443"
	echo " ./build.sh verify                        # verify every cert in ./server/*.crt and ./client/*.crt"
	echo " ./build.sh clean                         # delete everything, including root-ca and sub-ca dirs"
	echo " ./build.sh help                          # show this help"
}

help()
{
	usage
}

if [ $# -eq 0 ]; then
	help
elif [ $# -eq 1 ];then
	echo "Calling:$1"
	eval $1
else
	if [ "$1" = "ec" ];then
		FLAG_EC=1
	fi
	echo "Calling:$2"
	eval $2 $3
fi

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#					BASH SCRIPT ON LINUX/UNIX - END
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