Enterprise-Wide Security Architecture and Solutions Presentation Guide

3.6 AIX/6000

Figure 50. AIX/6000

Key Points

AIX Version 3.2 and AIX Version 4 for the RISC System/6000 currently offer

security policies and mechanisms for user authentication, password complexity,

user/port access controls, access control lists, auditing, trusted path, system

integrity, and user-resource limitations.

AIX/6000 is a secure system offering traditional UNIX type security, DCE security,

and ACL enhancements to support C2 functions.

Presentation Script

AIX Version 3.2 and AIX Version 4 for the RISC System/6000 currently offer

security policies and mechanisms for user authentication, password complexity,

user/port access controls, access control lists, auditing, trusted path, system

integrity, and user-resource limitations.

Hardware Key Lock:

AIX/6000 can be ordered with a hardware Key Lock. This

Key Lock has three positions:

•

Secure

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The system is not able to boot, from hard disk or from any other device like

floppy, CD, or tape.

•

Normal

The system is able to boot from the hard disk only. This is the most

common position.

•

Service (Maintenance)

The system tries to boot from removable devices like floppy, CD, or tape. If

the system cannot find any removable boot device, then the diagnostic

software from the hard disk will be loaded.

AIX/6000:

AIX/6000 is designed to meet the National Computer Security Center

(NCSC) Trusted Computer System Evaluation Criteria (TCSEC) Class C2, with

additional support exceeding C2 for extended granular access control,

configurable identification and authentication, and system integrity checking

mechanisms. For definition of the TCSEC security levels, see section 2.6.7,

“Security Evaluation Strategy” on page 88.

The security functions offered by AIX/6000 are:

•

Identification and Authentication

AIX uses standard password authentication. Encrypted passwords and other

security relevant user information are kept in a directory that is not

accessible to ordinary users.

•

Access Control Lists (ACL)

AIX uses a combination of traditional UNIX mode bits and an Access Control

List (ACL) mechanism. An AIX ACL allows the user to restrict or permit

access for individual users, groups or combinations of users and groups.

The access permission bits (and the ACLs, if present) are modifiable only by

the owner of the file or directory.

•

Object Reuse

Storage objects are objects that can be read-from and written-to by

non-privileged users and are accessed through kernel system calls. The

identified storage objects on AIX are filesystem objects, heap data (malloc′d

memory), a process′s memory address space, shared memory segments

and sockets.

•

Audit

AIX has the capability of creating an audit trail of security relevant events.

The auditable events are generated by preselection of user/event

combinations that can be configured by the system administrator. The audit

trail is kept (by default) in a directory that is not accessible by ordinary

users.

•

System Architecture

All processes in AIX reside in their own address space. A non-privileged

process may not read or write outside of its own address space. Segment

registers, which define these address spaces, are modifiable only by the

kernel. Other, non-memory TCP resources are protected from unauthorized

access by discretionary access control.

•

System Integrity

Chapter 3. Platform Security 105

The RISC System/6000 performs an extensive Power On Self Test (POST)

each time the system is cold booted to check the proper functioning of its

hardware and firmware.

Application Security:

Some applications have additional application dependent

security functions such as DCE (for more information about DCE see Chapter 4,

“DCE Security” on page 111 and 2.6.2, “DCE Security Services” on page 75),

DB2/6000 and CICS/6000. (In Chapter 5, “Application Security” on page 123 you

will find some additional information about DB2 and CICS)

AIX (IBM E3/CMW):

IBM E3/CMW for the AIX operating system is a multi-level

secure workstation operating system that is based on AIX/6000 V3.2.5. It is

designed to meet E3 (ITSEC) and B1 (TCSEC) with selected functionality from the

B2 and B3 level. For definition of the TCSEC and ITSEC security levels, see

section 2.6.7, “Security Evaluation Strategy” on page 88.

The IBM E3/CMW for the AIX operating system is only available from IBM UK.

For detailed information about this operating system you have to contact IBM

UK.

Additional Information:

For additional information on AIX 4 security see the

AIX

4 Security White Paper

from the EMEA AIX Security Center of Competence

available through WWW at http://w3.munich.ibm.com/CoC-Security/.

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