Simple bash script for generating self-signed certificates with wildcard

certgen

#!/bin/bash

function usage {
  echo "usage: $0 hostname"
  exit 0
}

HOSTNAME=$1
[ -z ${HOSTNAME} ] && usage

SERVER_KEY=${HOSTNAME}.key
SERVER_CERT=${HOSTNAME}.crt
DAYS=$((365*10))
SUBJECT="/C=BR/ST=RN/L=Natal/O=Anolis/CN=${HOSTNAME}"

openssl req -new -newkey rsa:2048 -nodes -x509 -sha256 \
  -days ${DAYS} \
  -subj "${SUBJECT}" \
  -keyout ${SERVER_KEY} \
  -reqexts SAN -extensions SAN \
  -config <(cat /etc/ssl/openssl.cnf <(printf "[SAN]\nsubjectAltName=DNS:*.${HOSTNAME}")) \
  -out ${SERVER_CERT}