Introduction

The critical point when it comes to job scheduling is the fact that it perfectly implements code injection across your network - which is what is usually called a vulnerability.

• Jobs are code, frequently shell commands, which are forwarded to remote servers and are executed in unattended mode.
• Users have to open their network and make their firewalls look like swiss cheese to allow a central server where a job scheduling product is operated to access any remote servers in their network.

JS7 introduces digital signing for the deployment of workflows and jobs.

• Digital signatures are created automatically and do not increase the effort for the deployment of objects.
• The security mechanism includes having certificates for digital signatures ready with the Controller and the Agents that execute jobs. If the signature does not match the available certificates then deployment is denied. This mechanism does not prevent an authorized person from deploying workflows but it prevents attackers from hijacking a user's identity and deploying malicious code.

Digital Signing

Digital signing is applied to workflows when performing JS7 - Deployment of Scheduling Objects.

• The signing process is performed by the JOC Cockpit and includes:
  • the user is assigned a private key and a certificate (X.509) or a public/private key (PGP),
  • to create a signature from the JSON representation of the workflow by use of the user's private key.
• The verification process is performed by the Controller and Agent which has been assigned the relevant scheduling object such as a workflow:
  • Both Controller and Agent instances look up available X.509 certificates and PGP public keys from files with the following locations:
    • Unix
      • X.509 certificates: ./config/private/trusted-x509-keys
      • PGP public key: ./config/private/trusted-pgp-keys
    • Windows
      • X.509 certificates: .\config\private\trusted-x509-keys
      • PGP public key: .\config\private\trusted-pgp-keys
  • If a certificate or public key is found then the signature of the deployed scheduling object is verified as follows:
    • X.509: 
      • the Root CA Certificate or Intermediate CA Certificate that was used originally to sign the user's Signing Certificate has to be in place or
      • the user's self-issued Signing Certificate has to be in place.
      • Using the Root CA Certificate or Intermediate CA Certificates simplifies certificate management as a single certificate file has to be present for any Controller or Agent instances. At the same time, security-aware administrators might prefer to deploy individual user Signing Certificates to Controller and Agent instances for more fine-grained control of which workflows and other objects can be deployed by a specific user to a given Agent. Similarly a specific Intermediate CA can be used to sign user Signing Certificates.
    • PGP: the public key available for the given user who signed the deployed scheduling object has to be present.
  • Controller and Agent instances make use of all certificate files and public key files available in the directories mentioned above. If none of the files matches the signature of a deployed scheduling object then deployment will be denied.

For creation of certificates for digital signing see JS7 - How to create X.509 Signing Certificates.

Security Levels

The JOC Cockpit is installed for one of the following security levels, see the JS7 - Security Architecture article for more information.

• Security Level Low
  • Inventory objects are automatically signed with the private key that is stored with the root account.
  • Signing is automatically applied when performing the Deploy operation.
• Security Level Medium
  • Inventory objects are automatically signed with the private key that is stored with the current user's account.
  • Signing is automatically applied when performing the Deploy operation.
• Security Level High
  • Scheduling objects are signed outside of JOC Cockpit:
    • Scheduling objects are exported using the Export operation and the option For signing.
    • The export archive file is transferred to a secure device, e.g. to a secure desktop machine.
    • The export archive file is extracted and each scheduling object file included is signed individually. 
      • The JS7 offers a script solutions, see JS7 - Signing Workflows for High Security Level.
      • For example the OpenSSL command line utility can be used as well as tools such as OpenPGP Kleopatra.
      • The signing step includes to create a signature file for each scheduling object file with the same name and the extension .sig (using X.509 certificates) or .asc (using PGP keys).
    • The signed scheduling object files and signature files are added to the same or to a new archive file.
  • The archive file that includes the scheduling object files and signature files is imported to JOC Cockpit. The deployment step is performed inline with the import step.

Further Resources

• JS7 - Deployment of Workflows for High Security Level
• JS7 - Signing Workflows for High Security Level
• JS7 - How to create X.509 Signing Certificates