Chapter 4: Integrity and security

1. Chapter 4: Integrity and security

2. Chapter objectives • After completing this chapter, you will be able to: • Describe the security and integrity needs of a large-scale operating environment • Describe the methods for serialization in a multi-user environment • Describe the built-in features that enable integrity and security • Describe the two-phase commit process and why it is needed • Describe the features needed from an add-on security package

3. Integrity

4. Integrity • Data Integrity – Primarily concerned with the accidental damage and recovery of data. • System Integrity – Ensures there is no way for any unauthorized program to: • Bypass store or fetch protection • Bypass security checking • Obtain control in an authorized state

5. Serialization Serialization means make a resource to be used on a one-at-a-time basis Methods to prevent concurrent updates: • Enqueing • Reserves • Locks • Global Resource Serialization (GRS)

6. Serialization - GRS

7. DFSMS DFSMS is the component of the operating system that controls all data set allocation and provides automatic backup of the data The DFSMS constructs: • Data class • Storage class • Management class • Storage group • ACS routines • Aggregate group • Copy Pools

8. SMS Constructs

9. Auditing Auditing is the process of ensuring that the information processing system complies with the installation security policy. Auditing may be: • A one time project (e.g; a snap inspection) or • An ongoing process System Management Facilities: writes audit records o DASD System Logger: log changes to data

10. Resource Recovery Services (RRS) RRS is the coordinating resource manager that assures that all the updates of the different data storage places are correctly coordinated and that the data integrity is maintained.

11. Application Resource Recovery Services (RRS) Resource Manager 1 Resource Manager 2 Resource Manager 3 RRS – Two-phase commit

12. Data backup and recovery Depending on the needs of the company Some tools: • FlashCopy (on 1 subsystem) • Remote Copy • Metro Mirror • Global Copy • Global Mirror • Global Mirror for IBM System z • Other backup and recovery solutions:

13. Data backup and recovery : FlashCopy

14. Data backup and recovery : Remote Copy

15. Data backup and recovery : Metro Mirror • When the application performs a write update operation to a primary volume, this is what happens: • Write to primary volume (DS6000 cache and NVS). • Write to secondary (DS6000 cache and NVS). • Signal write complete on the secondary DS6000. • Post I/O complete to host server.

16. Data backup and recovery: Global Copy The primary and secondary copies can be separated by any distance. The process is as follows: 1. The host server requests a write I/O to the primary DS6000. The write is staged through cache and non-volatile storage (NVS). 2. The write returns to the host server’s application. 3. At a later time, that is, in a non-synchronous manner, the primary DS6000 sends the necessary data so that the updates are reflected on the secondary volumes. The updates are grouped in batches for efficient transmission. 4. The secondary DS6000 returns write complete to the primary DS6000 when the updates are secured in the secondary DS6000 cache and NVS. The primary DS6000 then resets its change recording information.

17. Data backup and recovery: • Global Mirror • Global Mirror for IBM System z • Other backup and recovery solutions: • Data set level • Volume level • Application level

18. Security

19. Security IBM System Z partitioning achieves highest certification • System Z servers achieve Common Criteria Security Certification - Evaluation Assurance Level 5. • U. S. Government had rated the mainframe EAL4+ • PR/SM configures separate logical systems on the same hardware. It prevents the flow of information among logical partitions, providing a highly secure isolated environment. ATTENTION: Only the IBM mainframe partitions have attained an EAL5 rating.

20. z/OS Architecture : Enforced Isolation Virtual Storage (memory) Address Spaces Physical Storage Real Storage (frames) • Address Spaces - Unique area for executing and storing data for each user or program. • Frames – 4096-byte chunks of storage protected keys.

21. z/OS System Security Mechanisms

22. z/OS System Security • An attribute of z/OS such that there is no way for an unauthorized program: • To bypass store or fetch protection. • To bypass Password, RACF, or System Authorization Facility (SAF) mediated security checking, or, • To obtain control in an authorized state

23. z/OS Security

24. z/OS Certification • On March 11,2005, BSI awarded IBM EAL3+ certification for its flagship operating system z/OS 1.6 with the RACF optional feature. • The certification encompasses Controlled Access Protection Profile (CAPP) EAL3+ and Labeled Security Protection Profile (LSPP) EAL 3+. z/OS 1.5 and later with the RACF optional feature and DB2 Version 8, provides a multilevel security (MLS) solution.

25. Functions provided by z/OS Security Server • Traditional Functions • Identify and authenticate users. • Authorize users to protected resources. • Control users’ level of authorization to resources. • Log and report attempts to unauthorized. • Providing auditing functions. Newer Functions • Generation/Management of digital certificates. • Multilevel security

26. Summary • The New Mainframe: • Has several possibilities for to guaranty the integrity of the data • Data can be recovered when needed • Has several possibilities to make sure that the data is save and secure

27. ACEE APF Audit Backup DFSMS EAL ENQ Remote Copy FlashCopy Global Mirror GRS Integrity Lock Program states RACF Remote copy RRS SAF Security Serialization SMF SMS Storage protect key SVC System logger Two-phase commit Key terms in this chapter