Introduction
JS7 - Deployment of Scheduling Objects makes use of Signing Certificates to digitally sign workflows and other objects. Use of certificates for signing is not related to use of certificates to secure connections using HTTPS.
- Certificates for the specific use of code signing must be used.
- Users choose which approach they want to follow:
- Creating self-signed Certificates.
- Creating CA-signed Certificates.
Rollout of certificates to Controllers and Agents depends on the following choice:
- Self-signed Certificates have to be deployed from individual certificate files made available to Controllers and Agents.
- There is no security gap in use of self-signed Certificates. When users store certificate files to Controllers and Agents then this proves that they trust the certificates.
- CA-signed Certificates are not deployed to Controllers and Agents. Instead, the CA Certificate is deployed that was used to sign individual certificates.
- The approach includes that any signing certificate signed by the CA will be accepted for deployment of scheduling objects.
- For better control which certificates are made available for deplyoment, users might decide to use a specific Intermediate CA.
Self-signed Certificates and CA Certificates are deployed to the <data>/config/private/trusted-x509-keys
directory of Controller and Agent instances.
The article suggests the following steps for creation of both Self-signed Certificates and CA-signed Certificates:
- Create Private Key
- Create Certificate Signing Request (CSR)
- Create and sign Certificate
The article explains how to create Signing Certificates for use with JS7. Users who operate their own Certificate Authority might find different approaches and different responsibilities for the indicated steps. There's more than one way how to do it.
Examples in the article make use of OpenSSL 1.1.1k FIPS 25 Mar 2021 and JS7 Release 2.7.2. OpenSSL ships with Linux & other Unix OS and is available for Windows. The examples are focused on Unix.
Creating the Private Key and Certificate Signing Request
The steps to create a Private Key and Certificate Signing Request are the same for use of self-signed Certificates and CA-signed Certificates. 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 key_name
environment variable with a name of their choice that is used when creating related files.
Using ECDSA Encryption
# Specify key name used for file names key_name=signing # Create Private Key openssl ecparam -genkey -name secp384r1 -out "${key_name}".key # Create Certificate Signing Request (CSR) openssl req -new -sha512 -nodes \ -key "${key_name}".key \ -out "${key_name}".csr \ -subj "/C=DE/ST=Berlin/L=Berlin/O=SOS/OU=IT/CN=${key_name}"
Explanation:
- Private Key
- Choice of algorithm such as
secp256k1
,secp384r1
depends on support by the Java version used with JS7.
- Choice of algorithm such as
- 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
, StateST
, LocationL
, OrganizationO
, Organizational UnitOU
and Common NameCN
. - For self-signed Certificates 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 CA-signed Certificates the subject property holds the Certificate's Distinguished Name and the issuer property holds the CA Certificate's Distinguished Name. Both Distinguished Names should match except for the Common Name
CN
.
- The Distinguished Name is a unique identifier frequently using the hierarchy of Country
- The hash algorithm such as
- The following files will be created with this step:
- The
<key_name>
.key
file will hold the Private Key. - The
<key_name>
.csr
file will hold the Certificate Signing Request.
- The
Using RSA Encryption
# Specify key name used for file names key_name=signing # Create Private Key and Certificate Signing Request (CSR) openssl req -new -newkey rsa:4096 -sha256 -nodes \ -keyout "${key_name}".key \ -out "${key_name}".csr \ -subj "/C=DE/ST=Berlin/L=Berlin/O=SOS/OU=IT/CN=${key_name}"
Explanation:
- In the example the Private Key is created using the specified key size
4096
. - Choice of algorithm such as
secp256k1
,secp384r1
depends on support by the Java version used with JS7. - For use of the
-subj
option see Using ECDSA Encryption. - The following files will be created with this step:
- The
<key_name>
.key
file will hold the Private Key. - The
<key_name>
.csr
file will hold the Certificate Signing Request.
- The
Creating Certificates
Users have the option to create self-signed Certificates or CA-signed Certificates.
Creating self-signed Certificates
Users can run the following commands from the shell and replace the value of the key_name
environment variable with a name of their choice that is used when creating related files.
# Specify key name used for file names key_name=signing # Create Certificate openssl x509 -req -sha512 -days 3652 \ -signkey "${key_name}".key \ -in "${key_name}".csr \ -out "${key_name}".crt \ -extfile <(printf "keyUsage=critical,nonRepudiation,digitalSignature\nextendedKeyUsage=critical,codeSigning\n")
Explanation:
- The SHA option such as
-sha256, -sha384, -sha512
should preferably match the value of the option used when creating the Certificate Signing Request. - The
-days
argument optionally specifies the validity period of the resulting Certificate. - 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 a number of extensions recommended for use with Signing Certificates. - The following files will be created with this step:
- The
<key_name>
.crt
file will hold the self-signed Certificate.
- The
Self-signed Certificates must be copied to the <data>/config/private/trusted-x509-keys
directory of Controller and Agent instances.
Creating CA-signed Certificates
For CA-signed Certificates a Certificate Authority (CA) is required owning a CA Private Key and CA Certificate. The CA Private Key and CA Certificate will be used to sign Certificates on behalf of users.
- Setup of the Certificate Authority is performed once.
- Signing is performed for each Certificate on behalf of users.
Creating the Certificate Authority (CA)
The steps to create the CA Private Key and CA Certificate are similar to Creating the Private Key and Certificate Signing Request for self-signed Certificates.
Creating the CA Private Key and Certificate Signing Request
Steps include to create the signing-ca.key
CA Private Key file and signing-ca.csr
CA Certificate Signing Request file both 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.
# Specify key name used for file names ca_key_name=signing-ca # Create Private Key openssl ecparam -genkey -name secp384r1 -out "${ca_key_name}".key # Create Certificate Signing Request (CSR) openssl req -new -sha512 -nodes \ -key "${ca_key_name}".key \ -out "${ca_key_name}".csr \ -subj "/C=DE/ST=Berlin/L=Berlin/O=SOS/OU=IT/CN=${ca_key_name}"
Explanation:
- Explanations are the same as from Creating Private Key and Certificate Signing Request for self-signed Certificates.
- Users can choose Using ECDSA Encryption or Using RSA Encryption.
Creating the CA Certificate
Steps include to create the signing-ca.crt
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.
# Specify key name used for file names ca_key_name=signing-ca # Create Certificate openssl x509 -req -days 7305 \ -signkey "${ca_key_name}".key \ -in "${ca_key_name}".csr \ -out "${ca_key_name}".crt \ -extfile <(printf "basicConstraints=CA:TRUE\nkeyUsage=critical,nonRepudiation,keyCertSign,cRLSign\n")
Explanation:
- Explanations are similar to Creating self-signed Certificates with a few exceptions.
- The
-days
option specifying the validity period of the CA Certificate should be longer than the validity period of individual certificates. - The
-extfile
option specifies the Basic ConstraintCA:TRUE
which is required for a CA Certificate. Key Usage is limited to signing certificates.
- The
- The following files will be created with this step:
- The
signing-ca.crt
file will hold the CA Certificate.
- The
The CA Certificate must be copied to the <data>/config/private/trusted-x509-keys
directory of Controller and Agent instances.
Creating Signing Certificates
Creating the Signing Private Key and Certificate Signing Request
Steps include to create the signing.key
Private Key file and signing.csr
Certificate Signing Request file both in PEM format.
Users can run the following commands from the shell and replace the value of the key_name
environment variable with a name of their choice that is used when creating related files.
# Specify key name used for file names key_name=signing # Create Private Key openssl ecparam -genkey -name secp384r1 -out "${key_name}".key # Create Certificate Signing Request (CSR) openssl req -new -sha512 -nodes \ -key "${key_name}".key \ -out "${key_name}".csr \ -subj "/C=DE/ST=Berlin/L=Berlin/O=SOS/OU=IT/CN=${key_name}"
Explanation:
- Explanations are the same as with Creating Private Key and Certificate Signing Request for self-signed Certificates.
- Users can choose Using ECDSA Encryption or Using RSA Encryption.
Creating the Signing Certificate
Steps include to create the signing.crt
CA-signed Certificate file in PEM format.
Users can run the following commands from the shell and replace the value of the key_name
environment variable with a name of their choice that is used when creating related files:
# Specify key name used for file names key_name=signing # Create Certificate openssl x509 -req -sha512 -days 3652 \ -in "${key_name}".csr \ -CA signing-ca.crt \ -CAkey signing-ca.key \ -CAcreateserial \ -out "${key_name}".crt \ -extfile <(printf '\nkeyUsage=critical,nonRepudiation,digitalSignature\nextendedKeyUsage=critical,codeSigning\n')
Explanation:
- Explanations are similar to Creating self-signed Certificates with a few exceptions:
- The
-days
option specifying the validity period of the Signing Certificate should indicate a shorter period than the validity period of the CA Certificate. - The
-in
option specifies the location of the Certificate Signing Request. - The
-CA
option specifies the location of the CA Certificate file. - The
-CAkey
option specifies the location of the CA Private Key file. - The
-extfile
option specifies the Key Usage being limited to code signing.
- The
- The following files will be created with this step:
- The
signing.crt
file will hold the Signing Certificate..
- The
The Signing Certificate file does not require to be deployed to Controller and Agent instances. Instead, the CA Certificate file is deployed to Controller and Agent instances.