Bash Script to Generate OpenSSL Configuration File with Custom Parameters

cnf-generator.sh

#!/bin/bash

# 기본 설정
OUTPUT_CNF="openssl.cnf"

# 기본 값
COUNTRY="US"
STATE="California"
LOCALITY="San Francisco"
ORGANIZATION="Home"
COMMON_NAME="localhost"
EMAIL=""
DNS_NAMES=()
IP_ADDRESSES=()

# 색상 지정
green=$(tput setaf 2)
reset=$(tput sgr0)

# 사용법 안내 함수
usage() {
  echo "Usage: $0 [-c country] [-s state] [-l locality] [-o organization] [-n common_name] [-e email] [-d dns_names] [-i ip_addresses]"
  echo "  -c country         Country Name (default: US, e.g., KR)"
  echo "  -s state           State or Province Name (default: California, e.g., Seoul)"
  echo "  -l locality        Locality Name (default: San Francisco, e.g., Seoul)"
  echo "  -o organization    Organization Name (default: Home, e.g., My Company)"
  echo "  -n common_name     Common Name (default: localhost, e.g., myserver.local)"
  echo "  -e email           Email Address (default: '', e.g., admin@mydomain.com)"
  echo "  -d dns_names       Comma-separated list of DNS names (default: '', e.g., example.com,www.example.com)"
  echo "  -i ip_addresses    Comma-separated list of IP addresses (default: '', e.g., 192.168.1.1,192.168.1.2)"
  exit 1
}

# 옵션이 없으면 사용법 출력
if [ $# -eq 0 ]; then
  usage
fi

# 옵션 파싱
while getopts "c:s:l:o:n:e:d:i:" opt; do
  case ${opt} in
  c) COUNTRY=$OPTARG ;;
  s) STATE=$OPTARG ;;
  l) LOCALITY=$OPTARG ;;
  o) ORGANIZATION=$OPTARG ;;
  n) COMMON_NAME=$OPTARG ;;
  e) EMAIL=$OPTARG ;;
  d) IFS=',' read -r -a DNS_NAMES <<<"$OPTARG" ;;
  i) IFS=',' read -r -a IP_ADDRESSES <<<"$OPTARG" ;;
  *) usage ;;
  esac
done

# 디버깅 출력 함수
print_debug_info() {
  echo "COUNTRY=$COUNTRY"
  echo "STATE=$STATE"
  echo "LOCALITY=$LOCALITY"
  echo "ORGANIZATION=$ORGANIZATION"
  echo "COMMON_NAME=$COMMON_NAME"
  echo "EMAIL=$EMAIL"
  echo "DNS_NAMES=${DNS_NAMES[*]}"
  echo "IP_ADDRESSES=${IP_ADDRESSES[*]}"
}

# openssl.cnf 파일 생성 함수
generate_openssl_cnf() {
  {
    cat <<EOL
[ req ]
default_bits        = 2048
default_keyfile     = server-key.pem
distinguished_name  = subject
req_extensions      = req_ext
x509_extensions     = x509_ext
string_mask         = utf8only

[ subject ]
countryName         = Country Name (2 letter code)
countryName_default = $COUNTRY

stateOrProvinceName         = State or Province Name (full name)
stateOrProvinceName_default = $STATE

localityName          = Locality Name (e.g., city)
localityName_default  = $LOCALITY

organizationName         = Organization Name (e.g., company)
organizationName_default = $ORGANIZATION

commonName          = Common Name (e.g. server FQDN or YOUR name)
commonName_default  = $COMMON_NAME

emailAddress         = Email Address
emailAddress_default = $EMAIL

[ x509_ext ]
subjectKeyIdentifier    = hash
authorityKeyIdentifier  = keyid, issuer
basicConstraints  = CA:FALSE
keyUsage          = digitalSignature, keyEncipherment
subjectAltName    = @alternate_names
nsComment         = "OpenSSL Generated Certificate"
extendedKeyUsage  = serverAuth, clientAuth

[ req_ext ]
subjectKeyIdentifier  = hash
basicConstraints    = CA:FALSE
keyUsage            = digitalSignature, keyEncipherment
subjectAltName      = @alternate_names
nsComment           = "OpenSSL Generated Certificate"
extendedKeyUsage  = serverAuth, clientAuth

[ alternate_names ]
EOL

    # DNS 이름 추가
    for i in "${!DNS_NAMES[@]}"; do
      echo "DNS.$((i + 1)) = ${DNS_NAMES[$i]}"
    done

    # IP 주소 추가
    for i in "${!IP_ADDRESSES[@]}"; do
      echo "IP.$((i + 1)) = ${IP_ADDRESSES[$i]}"
    done
  } >"$OUTPUT_CNF"
  echo "${green}The cnf file has been created: $OUTPUT_CNF${reset}"
}

# 디버깅 정보 출력
print_debug_info

# openssl.cnf 파일 생성
generate_openssl_cnf

How to use

sh cnf-generator.sh [-c country] [-s state] [-l locality] [-o organization] [-n common_name] [-e email] [-d dns_names] [-i ip_addresses]

• -c country: Country Name (default: US, e.g., KR)
• -s state: State or Province Name (default: California, e.g., Seoul)
• -l locality: Locality Name (default: San Francisco, e.g., Seoul)
• -o organization: Organization Name (default: Home, e.g., My Company)
• -n common_name: Common Name (default: localhost, e.g., myserver.local)
• -e email: Email Address (default: "", e.g., admin@mydomain.com)
• -d dns_names: Comma-separated list of DNS names (default: "", e.g., example.com,www.example.com)
• -i ip_addresses: Comma-separated list of IP addresses (default: "", e.g., 192.168.1.1,192.168.1.2)

Example

sh cnf-generator.sh -c KR -s Seoul -l Seoul -o My Company -n myserver.local -e admin@mydomain.com -d example.com,www.example.com -i 192.168.1.1,192.168.1.2