Description of problem:
sshd rules will pass when sshd_required is set to 0 (unset)

Version-Release number of selected component (if applicable):
scap-security-guide-0.1.36-4.el7.noarch

How reproducible:
reliably

Steps to Reproduce:
1. open scap workbench, select sshd_use_approved_ciphers
2. sshd_required set to 0
3. scan machine that has Ciphers line commented / not present at all

Actual results:
pass

Expected results:
fail

Additional info:

All sshd rules has more or less same pattern in the oval (this is snippet from source code):
    <criteria operator="AND">                                                   
      <extend_definition comment="Installed OS is certified" definition_ref="installed_OS_is_certified" />
      <criteria comment="SSH is not installed or conditions are met"            
      operator="OR">                                                            
          <extend_definition comment="sshd is not required and not installed, or requirement is unset"
          definition_ref="sshd_not_required_or_unset" />                        
          <criteria comment="sshd is installed and configured" operator="AND">  
            <extend_definition comment="sshd is required and installed, or requirement is unset"
            definition_ref="sshd_required_or_unset" />                          
            <criterion comment="Check the Cipers list in /etc/ssh/sshd_config"  
            test_ref="test_sshd_use_approved_ciphers" />                        
          </criteria>                                                           
      </criteria>                                                               
    </criteria> 

That criterion "sshd_not_required_or_unset" is the culprit - what we really want in this situation is different logic - "sshd is not installed and either not required or unset".