Script to generate a self-signed certificate in bash

ssl-script.sh

#!/bin/bash

# Check if URL is passed as an argument
if [ $# -eq 0 ]; then
    echo "Error: Please provide a URL as an argument."
    exit 1
fi

# Set the URL
URL=$1

# Generate a private key for the CA
openssl genrsa -out my_ca.key 2048

# Create a self-signed certificate for the CA
openssl req -new -x509 -key my_ca.key -out my_ca.crt -days 365 -subj "/CN=My Local CA"

# Generate a private key
openssl genrsa -out $URL.key 2048

# Create a configuration file for the certificate
cat <<EOF >$URL.cnf
[ req ]
prompt             = no
default_bits       = 2048
distinguished_name = req_distinguished_name
req_extensions     = req_ext

[ req_distinguished_name ]
countryName                 = US
stateOrProvinceName         = California
localityName               = San Francisco
organizationName           = Example Inc.
commonName                 = $URL

[ req_ext ]
subjectAltName = @alt_names

[alt_names]
DNS.1 = $URL
DNS.2 = www.$URL
EOF

# Generate a Certificate Signing Request (CSR)
openssl req -new -key $URL.key -out $URL.csr -config $URL.cnf

# Sign the CSR with the local CA
openssl x509 -req -in $URL.csr -CA my_ca.crt -CAkey my_ca.key -CAcreateserial -out $URL.crt -days 365 -sha256

echo "Certificate signed by local CA for $URL has been generated:"
ls -l $URL.*