Table of Contents

Introduction

Prerequisites

The below scripts assume the following directory layout:

<ca> The directory <ca> is a placeholder. Any directory can be used.
- create_root_ca.sh
- create_certificate.sh
- certs
- csr
- private

Users should create the directories certs, csr and private like this:

Code Block

title	Create directories for Certificate Authority
linenumbers	true

mkdir certs csr private

Create Root CA Certificate

This step includes to create a private key (root-ca.key) and self-signed certificate (root-ca.crt) both in PEM format. As a result the following files will be created:

<ca>/certs/root-ca.crt
<ca>/private/root-ca.key

This step is performed just once. In case of repeated execution a new Root CA Certificate will be created and server certificates will have to be renewed.

SSL/TLS Certificates are used to secure HTTP connections between JOC Cockpit, Controller and Agents, for example JS7 - JOC Cockpit HTTPS Connections.

Users can choose one of the approachs specified with RFC5280:

Self-issued Certificates are created individually per user and are not applicable within reasonable effort for deploying individual certificate files to JS7 products.
Private CA-signed Certificates are issued by users who operate their own Private Certificate Authority (CA).
Public CA-signed Certificates are issued by a trusted Certificate Authority (CA) that validates the domain owner. They are not created by users but are purchased from the trusted CA and are not in scople of this article.

There is no difference in using a Private CA or Public CA concerning functionality of X.509 certificates, usage for Server Authentication / Client Authentication, or security of connections. The only difference is that users trust the Private CA that they set up on their own.

Examples in the article make use of JS7 Release 2.7.2, OpenSSL 1.1.1k FIPS 25 Mar 2021 for Unix and OpenSSL 3.1.4 24 Oct 2023 for Windows. OpenSSL ships with Linux & other Unix OS and is available for Windows.

Setting up the Private CA

Anchor
creating_private_key_and_csr
creating_private_key_and_csr
Creating the Private Key and Certificate Signing Request

Users have the option to use ECDSA or RSA for the encryption type applied to the Private Key.

Users can run the following commands from the shell and replace the value of the ca_key_name environment variable with a name of their choice that is used when creating related files.

Anchor
using_ca_private_key_ecdsa
using_ca_private_key_ecdsa
Using ECDSA Encryption

Code Block

language	bash
title	Example how to create Private Key and Certificate Signing Request using ECDSA encryption (Unix)
linenumbers	true

# Specify key name used for file names
ca_key_name=root-ca

# Create Private Key
openssl ecparam -genkey -name secp384r1 -out ${ca_key_name}.key

# Create Certificate Signing Request
openssl req -new -sha512 -nodes \
    -key ${ca_key_name}.key \
    -out ${ca_key_name}.csr \
    -subj "/C=DE/ST=Berlin/L=Berlin/O=SOS/OU=IT/CN=${ca_key_name}"

Expand

title	Windows version...

Code Block

language	text
title	Example how to create Private Key and Certificate Signing Request using ECDSA encryption (Windows)
linenumbers	true

@rem Specify key name used for file names
set ca_key_name=root-ca
 
@rem Create Private Key
openssl ecparam -genkey -name secp384r1 -out %ca_key_name%.key
 
@rem Create Certificate Signing Request 
openssl req -new -sha512 -nodes ^
    -key %ca_key_name%.key ^
    -out %ca_key_name%.csr ^
    -subj "/C=DE/ST=Berlin/L=Berlin/O=SOS/OU=IT/CN=%ca_key_name%"

Expand

title	Explanations...

Users should adjust the ca_key_name environment variable specifying a value that matches the purpose such as root-ca for a Root CA Certificate.
Private Key
- Choice of algorithm such as secp256k1, secp384r1 depends on support by the Java version used with JS7.
Certificare Signing Request
- The hash algorithm such as -sha256, -sha512 can be freely chosen.
- The -subj option specifies the Distinguished Name used for the subject of the CSR and resulting Certificate.
  - The Distinguished Name is a unique identifier frequently using the hierarchy of Country C, State ST, Location L, Organization O, Organizational Unit OU and Common Name CN.
  - For the Private Root CA Certificate the subject and issuer properties of the CSR/Certificate are the same. The minimum requirement is to specify the Common Name CN=<name> where <name> can freely be chosen.
  - For Private CA-signed Certificates the subject property holds the Certificate's Distinguished Name and the issuer property holds the Private CA Certificate's Distinguished Name using different values.
The following files will be created with this step:
- The root-ca.key file will hold the Private Key.
- The root-ca.csr file will hold the Certificate Signing Request.

Anchor
using_ca_private_key_rsa
using_ca_private_key_rsa
Using RSA Encryption

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title	Click to expand/collapse...

...

./create_root.shShell script create_root_ca.sh

Code Block

title	Run .create_root.sh shell script
linenumbers	true

Code Block

title
language	bash

#!/bin/bash

Example how to create Private Key and Certificate Signing Request using RSA encryption (Unix)
linenumbers	true

collapse

true

# Specify key name used for file names
ca_key_name=root-ca

# Create

Root

Private

CA

Key

private

and

key

Certificate

and

Signing

certificate set -e CA_HOME=$(dirname "$0") CA_HOME=$(cd "${CA_HOME}" >/dev/null && pwd) CA_CERTS=${CA_HOME}/certs CA_PRIVATE=${CA_HOME}/private # step 1 Generate Certificate Authority (CA) Private Key openssl ecparam -name prime256v1 -genkey -noout -out ${CA_PRIVATE}/root-ca.key # step 2: Generate Certificate Authority Certificate openssl req -new -x509 -sha256 -key ${CA_PRIVATE}/root-ca.key -out ${CA_CERTS}/root-ca.crt

Create Server Certificate

Request
openssl req -new -newkey rsa:4096 -sha256 -nodes \
    -keyout ${ca_key_name}.key \
    -out ${ca_key_name}.csr \
    -subj "/C=DE/ST=Berlin/L=Berlin/O=SOS/OU=IT/CN=${ca_key_name}"

Expand

title	Windows version...

Code Block

language	text
title	Example how to create Private Key and Certificate Signing Request using RSA encryption (Windows)
linenumbers	true

@rem Specify key name used for file names
set ca_key_name=root-ca
 
@rem Create Private Key and Certificate Signing Request
openssl req -new -newkey rsa:4096 -sha256 -nodes ^
    -keyout %ca_key_name%.key ^
    -out %ca_key_name%.csr ^
    -subj "/C=DE/ST=Berlin/L=Berlin/O=SOS/OU=IT/CN=%ca_key_name%"

Expand

title	Explanations...

In the example the Private Key is created using the specified key size 4096.
For use of the -sha256 hash algorithm and -subj option see Using ECDSA Encryption.
The following files will be created with this step:
- The root-ca.key file will hold the Private Key.
- The root-ca.csr file will hold the Certificate Signing Request.

Anchor
creating_ca_certificate
creating_ca_certificate
Creating the CA Certificate

Steps include to create the root-ca.crt Private CA-signed Certificate file in PEM format.

Users can run the following commands from the shell and replace the value of the ca_key_name environment variable with a name of their choice that is used when creating related files.

Code Block

language	bash
title	Example how to create CA Certificate (Unix)
linenumbers	true

# Specify key name used for file names
ca_key_name=root-ca

# Create Certificate
openssl x509 -req -sha512 -days 7305 \
    -signkey ${ca_key_name}.key \
    -in ${ca_key_name}.csr \
    -out ${ca_key_name}.crt \
    -extfile <(printf "basicConstraints=CA:TRUE\nkeyUsage=critical,nonRepudiation,keyCertSign,cRLSign\n")

Expand

title	Windows version...

Code Block

language	text
title	Example how to create CA Certificate (Windows)
linenumbers	true

@rem Specify key name used for file names
set ca_key_name=root-ca
 
@rem Create Certificate
set ca_csr_tmp_file=ca-csr-%RANDOM%.tmp
copy /Y NUL %ca_csr_tmp_file%
echo basicConstraints=CA:TRUE >> %ca_csr_tmp_file%
echo keyUsage=critical,nonRepudiation,keyCertSign,cRLSign >> %ca_csr_tmp_file%

openssl x509 -req -sha512 -days 7305 ^
    -key %ca_key_name%.key ^
    -in %ca_key_name%.csr ^
    -out %ca_key_name%.crt ^
    -extfile %ca_csr_tmp_file%

del /q %ca_csr_tmp_file%

Expand

title	Explanations...

The SHA option such as -sha256, -sha384, -sha512 can be freely chosen.
The -days option specifies the validity period of the CA Certificate that should be longer than the validity period of individual certificates signed by the CA later on.
The -signkey option specifies the location of the Private Key file created from the previous step.
The -in option specifies the location of the Certificate Signing Request file created from the previous step.
The -out option specifies the location of the resulting Certificate file.
The -extfile option specifies the Basic Constraint CA:TRUE which is required for a CA Certificate. Key Usage is limited to signing certificates.
The following files will be created with this step:
- The root-ca.crt file will hold the CA Certificate.

Creating SSL/TLS Server Certificates

For a given server next steps includes to create the Private Key and Certificate Signing Request (CSR). The resulting Server Certificate will be signed by the Private CAThis step includes to create a private key and certificate request (CSR). The resulting server certificate will be signed.

This step is performed for each server certificate Server Certificate that should be created:

...

.

...

Users can run the following commands from the shell and replace the value of the server_name environment variable with a name of their choice that is used when creating related files.

Creating the Private Key and Certificate Signing Request

Anchor
using_server_private_key_ecdsa
using_server_private_key_ecdsa
Using ECDSA Encryption

...

title	Run .create_root.sh shell script
linenumbers	true

...

Code Block

language	bash
title	Shell script create_certificate.shExample how to create Private Key and Certificate Signing Request using ECDSA encryption (Unix)
linenumbers	true

#!/bin/bash Specify key name used for file names
server_name=myhost

# Create certificate for Server Authentication and Client Authentication

# Example
# ./create_certificate.sh apmaccs

set -e

CA_HOME=$(dirname "$0")
CA_HOME=$(cd "${CA_HOME}" >/dev/null && pwd)

CA_CERTS=${CA_HOME}/certs
CA_CSR=${CA_HOME}/csr
CA_PRIVATE=${CA_HOME}/private


# Specify server for which the certificate should be created
SERVER=$1


# Step 1 - Generate Private Key andPrivate Key
openssl ecparam -genkey -name secp384r1 -out ${server_name}.key

# Create Certificate Signing Request
openssl req -new -sha512 -nodes \
    -key ${server_name}.key \
    -out ${server_name}.csr \
    -subj "/C=DE/ST=Berlin/L=Berlin/O=SOS/OU=IT/CN=${server_name}"

Expand

title	Windows version...

Code Block

language	text
title	Example how to create Private Key and Certificate Signing Request using ECDSA encryption (Windows)
linenumbers	true

@rem Specify key name used for file names
set server_name=myhost

@rem Create Private Key
openssl ecparam -genkey -name secp384r1 -out %server_name%.key

@rem Create Certificate Signing Request
openssl req -new -sha512 -nodes ^
    -

config

key

${CA_HOME}/openssl-cert.config -extensions 'standard exts' -nodes \ -days 7300

%server_name%.key ^
    -out %server_name%.csr ^
    -subj "/C=DE/ST=Berlin/L=Berlin/O=SOS/OU=IT/CN=%server_name%"

Expand

title	Explanations...

Explanations are the same as for Using ECDSA Encryption.

Anchor
using_server_private_key_rsa
using_server_private_key_rsa
Using RSA Encryption

Expand

title	Click to expand/collapse...

Code Block

language	bash
title	Example how to create Private Key and Certificate Signing Request using RSA encryption (Unix)
linenumbers	true

# Specify key name used for file names
server_name=myhost

# Create Private Key and Certificate Signing Request
openssl req -new -newkey rsa:4096 -sha256 -nodes \
    -keyout ${

CA

server_

PRIVATE

name}

/${SERVER}

.key \
    -out ${

CA

server_name}.csr \
    -subj "/C=DE/ST=Berlin/L=Berlin/O=SOS/OU=IT/CN=${server_name}"

Expand

title	Windows version...

Code Block

language	text
title	Example how to create Private Key and Certificate Signing Request using RSA encryption (Windows)
linenumbers	true

@rem Specify key name used for file names
set server_name=myhost

@rem Create Private Key and Certificate Signing Request
openssl req -new -newkey rsa:4096 -sha256 -nodes ^
    -keyout %server_name%.key ^
    -out %server_name%.csr ^
    -subj "/C=DE/ST=Berlin/L=Berlin/O=SOS/OU=IT/CN=%server_name%"

Expand

title	Explanations...

Explanations are the same as for Using RSA Encryption.

Creating the Server Certificate

Code Block

language	bash
title	Example how to create and sign Server Certificate (Unix)
linenumbers	true

# Specify server for which the certificate should be created
server_name=myhost

# Create and sign CSR}/${SERVER}.csr


# Step 2 - Generate and Sign the Server Certificate
openssl x509 -req -sha512 -days 3652 \
    -in ${CA_CSR}/${SERVERserver_name}.csr \
    -CA ${CA_CERTS}/root-ca.crt \
    -CAkey ${CA_PRIVATE}/root-ca.key \
    -CAcreateserial \
    -out ${CAserver_CERTSname}/${SERVER}.crt -days 7300 \
    -extfile <(printf "'subjectAltName=DNS:apmaccs,DNS:apmaccs.sos\nnsCertType = client, server%s\nkeyUsage = digitalSignaturecritical, keyEncipherment,digitalSignature\nextendedKeyUsage = serverAuth, clientAuth\n' "${server_name}")

...

OpenSSL configuration file openssl-cert.config

Expand

title	Windows version...

Code Block

title

language	text
title	Example how to create and sign Server Certificate (Windows)
linenumbers	true

[ req ] prompt = no distinguished_name = standard dn [ standard dn ] commonName = apmaccs countryName = DE localityName = Berlin organizationName = SOS organizationalUnitName = JS7 stateOrProvinceName = Berlin [ standard exts ] extendedKeyUsage = serverAuth,clientAuth

@rem Specify key name used for file names
set server_name=myhost

@rem Create and sign Server Certificate
set server_crt_tmp_file=server-crt-%RANDOM%.tmp
copy /Y NUL %server_crt_tmp_file%
echo subjectAltName=DNS:%server_name% >> %server_crt_tmp_file%
echo keyUsage=critical,keyEncipherment,digitalSignature >> %server_crt_tmp_file%
echo extendedKeyUsage=serverAuth,clientAuth >> %server_crt_tmp_file%
 
openssl x509 -req -sha512 -days 3652 ^
    -in %server_name%.csr ^
    -CA root-ca.crt ^
    -CAkey root-ca.key ^
    -CAcreateserial ^
    -out %server_name%.crt ^
    -extfile %server_crt_tmp_file%

del /q %server_crt_tmp_file%

Expand

title	Explanations...

The following files will be created for the given server:
- myhost.crt: the Server Certificate
For operation with JS7 JOC Cockpit, Controller and Agents users can add
- the Private Key and Server Certificate to a keystore.
- the Root CA Certificate to a truststore.
- For details see JS7 - How to add SSL TLS Certificates to Keystore and Truststore

Resources

Shell Scripts

As an alternative to running OpenSSL commands in an interactive shell, scripts are provided that perform this task.

The below scripts assume the following directory layout:

<ca> The directory <ca> is a placeholder. Any directory can be used.
- create_root_ca.sh
- create_server_certificate.sh
- certs
- csr
- private

The sub-directories certs, csr and private will be created should they not exist.

Creating the Private Root CA Certificate

Download: create_root_ca.sh

The following files will be created when executing the script:

<ca>/certs/root-ca.crt
<ca>/csr/root-ca.csr
<ca>/private/root-ca.key

This step is performed just once. In case of renewal of the Root CA Certificate any Server Certificates will have to be renewed.

Code Block

language	bash
title	Run .create_root_ca.sh shell script
linenumbers	true

# Description
# create_root_ca.sh --key-name=<basename> --subject=<distinguished-name> --days=<number-of-days>

# Example for use with defaults
./create_root_ca.sh

# Example for use with basename
./create_root_ca.sh --key-name=ca-root

# Example applying specific distinguished name and lifetime
./create_root_ca.sh --subject="/C=DE/ST=Berlin/L=Berlin/O=SOS/OU=IT/CN=JS7 CA" --days=7660

The shell script is optionally executed with the following arguments:

--key-name
- The basename of the key without extension. Default: root-ca
--subject
- The distinguished name that is used as the subject of the CA Certificate. Default: /C=DE/ST=Berlin/L=Berlin/O=SOS/OU=IT/CN=Root CA
--days
- The lifetime of the certificate is specified by the number of days. Default: 7305
- Consider that Server Certificates have to be renewed if the Root CA Certificate expires.

Creating a Server Certificate

Download: create_server_certificate.sh

The following files will be created with <server> being a placeholder for the hostname for which a certificate should be created.

<ca>/certs/<server>.crt
<ca>/csr/<server>.csr
<ca>/private/<server>.key

This step is performed for each Server Certificate that should be created.

Code Block

language	bash
title	Run .create_server_certificate.sh shell script
linenumbers	true

# Description
# create_server_certificate.sh --dns=<hostname>[,<hostname>] --key-name=<basename> --subject=<distinguished-name> --days=<number-of-days>

# Example for use with DNS and lifetime
./create_server_certificate.sh --dns=centostest-primary --days=365

# Example for use with DNS, key name and lifetime
./create_server_certificate.sh --dns=centostest-primary,centostest-primary.sos --key-name=centostest-primary --days=4017

# Example for use with DNS, subject and lifetime
./create_server_certificate.sh --dns=centostest-primary,centostest-primary.sos --subject="/C=DE/ST=Berlin/L=Berlin/O=SOS/OU=IT/CN=centostest-primary.sos" --days=4017

The shell script is executed with the following arguments:

--dns (required)
- The DNS hostname of the server that should be assigned the certificate. A server can be assigned more than one DNS hostname, for example the FQDN can extend the hostname. Only DNS hostnames that are added to the certificate can be used later on to establish secure HTTPS connections.
--key-name
- The basename of the key without extension. Default: root-ca
--subject
- The distinguished name that is used as the subject of the Server Certificate. Default: /C=DE/ST=Berlin/L=Berlin/O=SOS/OU=IT/CN=<dns>
- The CN attribute must specify the server's hostname. By default the first hostname specified with the --dns option is used.
--days
- The lifetime of the certificate is specified by the number of days. Default: 3652

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Key

Introduction

Prerequisites

Create Root CA Certificate

Setting up the Private CA

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creating_private_key_and_csr
creating_private_key_and_csr
Creating the Private Key and Certificate Signing Request

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using_ca_private_key_ecdsa
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Using ECDSA Encryption

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using_ca_private_key_rsa
using_ca_private_key_rsa
Using RSA Encryption

Create Server Certificate

Anchor
creating_ca_certificate
creating_ca_certificate
Creating the CA Certificate

Creating SSL/TLS Server Certificates

Creating the Private Key and Certificate Signing Request

Anchor
using_server_private_key_ecdsa
using_server_private_key_ecdsa
Using ECDSA Encryption

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using_server_private_key_rsa
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Using RSA Encryption

Creating the Server Certificate

Resources

Shell Scripts

Creating the Private Root CA Certificate

Creating a Server Certificate

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Versions Compared

Old Version 1

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Key

Introduction

Prerequisites

Create Root CA Certificate

Setting up the Private CA

Anchorcreating_private_key_and_csrcreating_private_key_and_csrCreating the Private Key and Certificate Signing Request

Anchorusing_ca_private_key_ecdsausing_ca_private_key_ecdsaUsing ECDSA Encryption

Anchorusing_ca_private_key_rsausing_ca_private_key_rsaUsing RSA Encryption

Create Server Certificate

Anchorcreating_ca_certificatecreating_ca_certificateCreating the CA Certificate

Creating SSL/TLS Server Certificates

Creating the Private Key and Certificate Signing Request

Anchorusing_server_private_key_ecdsausing_server_private_key_ecdsaUsing ECDSA Encryption

Anchorusing_server_private_key_rsausing_server_private_key_rsaUsing RSA Encryption

Creating the Server Certificate

Resources

Shell Scripts

Creating the Private Root CA Certificate

Creating a Server Certificate

Links

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creating_private_key_and_csr
creating_private_key_and_csr
Creating the Private Key and Certificate Signing Request

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using_ca_private_key_ecdsa
Using ECDSA Encryption

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using_ca_private_key_rsa
using_ca_private_key_rsa
Using RSA Encryption

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creating_ca_certificate
creating_ca_certificate
Creating the CA Certificate

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using_server_private_key_ecdsa
using_server_private_key_ecdsa
Using ECDSA Encryption

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using_server_private_key_rsa
using_server_private_key_rsa
Using RSA Encryption