Digital Certificate Monitoring

Log File Monitor supports the monitoring of Digital Certificates. This is achieved by using a file type of *CERT when creating the Log File Monitor rule group. This allows, amongst other uses, the ability to detect when certificates that are getting near to their expiry dates or for any certificates that re missing.

When *CERT is specified as the File type, three fields that are unique to Digital Certificate monitoring are displayed.

Certificate store

This specifies the certificate store that contains the digital certificates. The default setting is *SYSTEM.

*SYSTEM The *SYSTEM certificate store is specified
*OBJECTSIGNING The *OBJECTSIGNING certificate store is specified
*SIGNATUREVERIFICATION The *SIGNATUREVERIFICATION certificate store is specified
path Enter the IFS path and file name of the certificate store (extension of .kbd)
Certificate

This specifies the certificates to be monitored by checking the label attribute of the certificates. The default setting is *ALL.

*ALL All certificates found in the store location are retrieved
generic* All certificates in the store that match the generic name are retrieved
name A record is returned for the named certificate whether the certificate is found in the store or not. The Exists attribute indicates whether or not the certificate was found. If it is not found only the Name and Exists attributes contain values, as all the other attributes return blanks or zeros.

If *ALL or generic is specified, one record for each matching certificate is returned.

Certificate store password

This specifies the password required to access the certificate store.

&Varname Specify the name of a substitution variable that contains the required password. The substitution variable can be up to 128 characters.
value Enter a specific password
******** A previously entered specific password is denoted by asterisks. The actual password is not displayed. To keep the existing password, leave the field set to all asterisks. To change the password or to use a substitution variable, overtype with the new value.
Field Definitions

With a Field Type of *CERT, you can only define one normal field; CERTDATA with a type of *CHAR. This field contains XML data describing all the attributes of the certificate.

Any other fields must be type *CALC and typically use an %XML function to extract an attribute of the certificate from the XML data in the *CHAR field.

On the second page of the Log File MonitorRule Group for *CERT file type, five fields are automatically set.

CERTDATA *CHAR Certificate data
CERT *CALC Certificate label
ENDDATE *CALC Validity period end date
EXPDAYS *CALC Validity period days remaining
EXISTS *CALC Certificate exists

You can manually create fields and add the functions, but it is recommended that F4=Prompt is used in the Name field. This then displays the 'Select Certificate Attribute from where all the supported certificate attributes are listed. Once an attribute is selected the field is populated with the field name, type description and function.

Common uses for Digital Certificate Monitoring

The two commonest uses for Digital Certificate Monitoring are:

  • Detect certificates nearing expiry
  • Detect missing certificates
To detect certificates near their expiry date:
  1. Set the Store and set the Certificate to *ALL, generic or the specific name of the certificate to be monitored.
  2. Add rule criteria to check EXPDAYS is less then, for example, 30.

The EXPDAYS field definition then returns the number of days to go until the certificate expires. If the certificate has expired, zero is returned.

To detect certificates that are missing: 
  1. Set the Store and the set Certificate to a specific name. Do not use *ALL or generic.
  2. Add rule criteria to check for EXISTS = N.

If the EXISTS field definition returns N, the certificate is missing.

Supported Attributes

A certificate is identified by its 'Label' attribute. This value is located in the 'Certificate' XML tag in Log File Monitor and is recognized by the CERT field in Log File Rule Groups.

There is a 'Name' attribute (Subject's common name). This value is located in the 'Name' XML tag and is recognized by the NAME field. It is usually the same value as the 'Label' attribute but it may be different or a blank value.

STRDATE and STRTIME indicate from when a certificate is valid and ENDDATE and ENDTIME indicate when it expires.

EXPDAYS is not an actual attribute of the certificate but is calculated by Log File Monitor by comparing ENDDATE with today's date.

All of the following attributes are supported when using Digital Certificate Monitoring.

CERT Certificate label
NAME Subject's common name
EXISTS Certificate exists
STRDATE Validity period start date
STRTIME Validity period start time
ENDDATE Validity period end date
ENDTIME Validity period end time
EXPDAYS Validity period days remaining
COUNTRY Subject's country or region
STATE Subject's state or province
LOCALITY Subject's locality
ORG Subject's organization
UNIT Subject's organizational unit
POSTCODE Subject's postal code
ISSNAME Issuer's common name
ISSCOUNTRY Issuer's country or region
ISSSTATE Issuer's state or province
ISSLOCAL Issuer's locality
ISSORG Issuer's organization
ISSUNIT Issuer's organizational unit
ISSPCODE Issuer's postal code
CRLLOC CRL location
DOMAIN Domain name
EMAILADDR Email address
IPADDR IP address
KEYSTG Key storage location
LDAPSVR LDAP server name
PRIVATE Private key indicator
PVTKEYLBL Private key label
SRLNBR Serial number
TRUSTED Trusted status
DIGSIG Digital certificate extension
NONREPUD Non-repudiation extension
KEYENCIPH Key encipherment extension
DATENCIPH Data encipherment extension
KEYAGREE Key agreement extension
KEYCERTSIG Key certificate signature extension
CRLSIG CRL signature extension
ENCIPHONLY Encipher only extension
DECIPHONLY Decipher only extension