z/OS Basic Skills Information Center. Security on z/OS

26 Pages·2010·0.096 MB·English

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z/OS Basic Skills Information Center
Security on z/OS

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z/OS Basic Skills Information Center
Security on z/OS
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Contents
Overview of security on z/OS . . . . . v Chapter 3. z/OS and system integrity . . 7
Whatistheauthorizedprogramfacility? . . . . . 8
Chapter 1. Roles in z/OS security. . . . 1 Whatisstorageprotection? . . . . . . . . . 9
Whoisthesecurityadministrator? . . . . . . . 1 Controllingcross-memorycommunication . . . . 9
Whoisthesecurityauditor? . . . . . . . . . 2
Whoisthesystemoperator? . . . . . . . . . 2 Chapter 4. Security for z/OS UNIX . . . 11
Chapter 2. Security facilities of z/OS . . 3 Notices . . . . . . . . . . . . . . 13
WhatisSAF? . . . . . . . . . . . . . . 3 Programminginterfaceinformation . . . . . . 14
WhatisIBMSecurityServer?. . . . . . . . . 4 Trademarks . . . . . . . . . . . . . . 14
WhatisRACF? . . . . . . . . . . . . . 5
©CopyrightIBMCorp.2006,2010 iii
iv z/OSBasicSkillsInformationCenter: Securityonz/OS
Overview of security on z/OS
An installation's data and application programs must be protected from
unauthorized access — both internally (employees) and externally (customers,
business partners, or hackers). In working with z/OS®, you need to understand the
importance of security and the z/OS facilities used to implement it.
Over time, it has become easier to create and access computerized information. No
longer is system access limited to a handful of highly skilled programmers.
Information can now be created and accessed by almost anyone who takes a little
time to become familiar with the newer, easier-to-use, high-level inquiry languages.
More and more people are becoming increasingly dependent on computer systems
and the information they store in these systems.As general computer literacy and
the number of people using computers has increased, the need for data security
has taken on a new measure of importance. No longer can the installation depend
on keeping data secure simply because no one knows how to access the data.
Making data secure encompasses more than just making confidential information
inaccessible to those who should not see it. It also includes preventing the
inadvertent destruction of files by people who may not even know that they are
improperly manipulating data. Good data security practices reduces the likelihood
of unauthorized persons accessing, modifying, or destroying data, either
inadvertently or deliberately.
Access, in a computer-based environment, means the ability to do something with
a computer resource (for example, use, change, or view something).Access control
is the method by which this ability is explicitly enabled or restricted.
Computer-based access controls are called logical access controls. These are
protection mechanisms that limit users' access to information to only what is
appropriate for them.
Logical access controls are often built into the operating system, or may be part of
the logic of application programs or major utilities, such as database management
systems. They may also be implemented in add-on security packages that are
installed into an operating system; such packages are available for a variety of
systems, including PCs and mainframes.Additionally, logical access controls may
be present in specialized components that regulate communications between
computers and networks.
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vi z/OSBasicSkillsInformationCenter: Securityonz/OS
Chapter 1. Roles in z/OS security
Mainframe environments tend to be well-structured, with formal roles, such as
systems programmer, security administrator, and auditor, that are assigned to
separate individuals. This separation of duties is a cornerstone of security and
mainframe management. In essence,Ability should not exceedAuthority.
Asignificant difference to note, when deploying a mainframe as opposed to a
distributed server environment, is the way in which job definitions and roles are
defined and how the IT staff is assigned duties, as explained here:
v In a distributed environment, people often handle multiple duties in the interest
of efficiency. For example, an operator who has the authority to shut down the
system might also have the ability to delete user IDs.
However, giving staff the authorization for many tasks, while in one sense
efficient, opens the door for abusing this power. For example, a database
administrator who sold a corporation's information to its competition might
have the ability to hide these actions from auditors.
v In a mainframe environment, by contrast, skills are generally more focused on a
specific responsibility. That is, there tends to be more separation of duties. Each
mainframe support person is a specialist, yet mainframes usually operate with
fewer support personnel relative to the size of the user community because of
the centralized nature of mainframe management tools. The efficiency derives
from the platform architecture, not from people sharing duties.
In the past, it was the mainframe system programmer who, working with
management, decided the overall security policy and procedures. Today companies
are seeking higher levels of security, so they often appoint a separate security
manager. The system programmer might not have direct responsibility for security,
other than advising the security manager about new products. Separation of duties
is necessary to prevent any one individual from having uncontrolled access to the
system.
Who is the security administrator?
The security administrator is the focal point for planning security in the
installation. RACF® gives the security administrator (that is, the user defined with
the SPECIALattribute) many responsibilities both at the system level and at the
group level.
The security administrator is responsible for:
v Determining which RACF functions to use
v Identifying the level of RACF protection
v Identifying which data RACF is to protect
v Defining administrative structures and users.
Asystem administrator assigns user IDs and initial passwords and ensures that the
passwords are non-trivial, random, and frequently changed. Because the user IDs
and passwords are so critically important, special care must be taken to protect the
files that contain them.
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In z/OS, the security administrator can use RACF Remote Sharing Facility (RRSF) to
administer and maintain RACF databases distributed throughout the enterprise.
This facility:
v Provides improvements in system performance, system management, system
availability, and usability
v Helps to ensure that data integrity is retained across system or network failures
and delays
v Informs you when key events have occurred and returns output to view at your
convenience.
Who is the security auditor?
Security audits are a way of examining a system, policy or process for violations
and exposures.
Auditing is the process of ensuring that the information processing system
(hardware, software, liveware, middleware, policies, and procedures) complies
with the installation security policy.Auditing may be:
v Aone-time project such as a snap inspection, or
v An ongoing process pursuant to policies.
Security audits are a catch-all that have been used for actions ranging from checks
on physical security to implementation of the information security plan.
The two types of information security audits can be termed preemptive and
reactive.As their names indicate, preemptive audits test security controls. Reactive
audits respond to potential security breach events.
Who is the system operator?
Console security means controlling which commands operators can enter on their
consoles to monitor and control z/OS.
How you define command authorities for your consoles, or control logon for
operators, enables you to plan the operations security of your z/OS system or
sysplex. In a sysplex, because an operator on one system can enter commands that
affect the processing on another system, your security measures become more
complicated and you need to plan accordingly.
When implementing console security, the installation can control which commands
operators can enter on their consoles to monitor and control z/OS. To do so, the
installation uses RACF and the CONSOLxx member in PARMLIB.
For multiple console support (MCS) consoles, you can use the following to control
whether operators can enter commands from a console:
v TheAUTH keyword on the CONSOLE statement of CONSOLxx
v The LOGON keyword of the DEFAULT statement and RACF commands and
profiles.
For extended MCS consoles, you can control what an authorized SDSF or TSO/E
user can do during a console session. Because an extended MCS console can be
associated with a TSO/E user ID and not a physical console, you might want to
use RACF to limit not only the z/OS commands a user can enter, but from which
TSO/E terminals the user can enter the commands.
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