LJK/Security Reference Manual


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SYSEXE

Ensure system program images are valid.

Violation reports

Constraint Nature of the violation
CHECKSUM Image in system directory not checksummed in violation of policy

Description

Exemptions within the (DISK, CHECKSUM) element specify checksum values for particular files on disk. The test for the CHECKSUM constraint within this facility determines whether such an exemption has been established for all files in the SYS$SYSROOT:[*...] tree with a file type of .EXE.
Default policy Checksums of images in the SYS$SYSROOT:[*...] tree are required. Customizing Setting the (DISK, SYSEXE, CHECKSUM) limit TRUE is appropriate for most environments since upgrading to a new version of a layered product should be done in a controlled fashion. selector

Limits

Constraint Value Default
CHECKSUM FALSE or TRUE TRUE

Exemptions

Constraint Value Parameters
CHECKSUM FALSE or TRUE <node>,<filespec>
Practical considerations After upgrading layered products, checksums in the policy should be adjusted as soon as possible to match the new values.

SYSEXEPROT

Ensure that protections on files with type .EXE in SYS$COMMON:[*] fall within the restrictions set by policy.

Violation reports

Constraint Nature of the violation
ABSOLUTLO Access is narrower than permitted by policy
ABSOLUTHI Access is wider than permitted by policy
NOSYSOWNER File is owned by a system UIC in violation of policy
PERCENTLO Fewer users can access than permitted by policy
PERCENTHI More users can access than permitted by policy
SYSOWNER File is not owned by a system UIC in violation of policy
VERSIONMAX File version number is higher than allowed by policy

Description

If a file's protection setting is not restrictive enough, unauthorized users will be able to read, write, execute, or delete the file in question. If the setting is too restrictive, users generally find a less acceptable way of sharing information to get their job done. Typically, they share their password or make an unauthorized copy of the file somewhere else.

The purpose of this test is to ensure that file protection settings are within the limits set by the security manager.

The ABSOLUTLO and ABSOLUTHI tests measure the UIC-based protection mask directly. The PERCENTLO and PERCENTHI tests measure the result of protection (including ACL protection) in terms of the percentage of usernames given access.

Violations for protection-related DISK facility elements are not reported regarding only the writeability of CDROM disks since the apparent writeability is just an illusion.

Default policy Files have a system owner.

The file protection setting must allow at least the system to read, write, access, and delete the file. By default, the weakest acceptable file setting allows the system and owner to read, write, execute, and delete the file, and also allows other users in the owner's UIC group and the world to read and execute the file.

By default, a minimum of 0 percent of users must have access and a maximum of 100 percent of users may have READ and EXECUTE access with a maximum of 1 percent having WRITE, EXECUTE and DELETE access. Customizing Limits for constraints ABSOLUTLO and ABSOLUTHI take the same form as a standard VMS file protection setting. The syntax for this is explained in some detail in VMS documentation. The default settings shown in the limits table below are good examples of how to specify which class of users are allowed which type of access. These are the codes involved:

selector Limits for constraints PERCENTLO and PERCENTHI can take a selector consisting of a VMS file access type: READ, WRITE, EXECUTE, DELETE or CONTROL. If no selector is specified, customization commands apply to all possible selector values.

Limits

Constraint Value Default
ABSOLUTLO Any Protection (S:RWED,O,G,W)
ABSOLUTHI Any Protection (S:RWED,O:RWED,G:RE,W:RE)
NOSYSOWNER FALSE or TRUE FALSE
PERCENTLO 0-100 0
PERCENTHI 0-100 R:100,W:1,E:100,D:1,C:1
SYSOWNER FALSE or TRUE TRUE
VERSIONMAX 0-32767 0

Exemptions

Constraint Value Parameters
ABSOLUTLO Any Protection <node>, <filespec>
ABSOLUTHI Any Protection <node>, <filespec>
NOSYSOWNER FALSE or TRUE <node>,<filespec>
PERCENTLO 0-100 <node>, <filespec>
PERCENTHI 0-100 <node>, <filespec>
SYSOWNER FALSE or TRUE <node>,<filespec>
VERSIONMAX 0-32767 <node>,<filespec>
Practical considerations Files of type .EXE in SYS$COMMON:[*] are typically protected to allow execution by users. Some of them, particularly those provided by DEC, also allow Read access by individual users.

6.6 QUEUE tests

Tests in the QUEUE facility deal with print and batch queues.

Exemptions are based on node name and queue name.


ACLIDENT

Ensure that identifier types used in access control lists conform to policy.

Violation reports

Constraint Nature of the violation
NOGENERAL General identifier used in violation of policy
NOSYSTEM System-defined identifier used in violation of policy
NOUIC UIC identifier used in violation of policy

Description

Use of UIC identifiers directly in access control lists leads to problems if user responsibilities are changed, since control of the access they have been granted is distributed throughout the system.

The purpose of this test is to ensure that identifiers used in Identifier Access Control Entries are of acceptable types.

Default policy Identifiers in ACLs must not be UIC identifiers. Customizing The options of prohibiting General and System identifiers are provided for flexibility, but are not useful in most circumstances. The main customization which might be desired is to remove the prohibition against the use of UIC identifiers. selector

Limits

Constraint Value Default
NOGENERAL FALSE or TRUE FALSE
NOSYSTEM FALSE or TRUE FALSE
NOUIC FALSE or TRUE TRUE

Exemptions

Constraint Value Parameters
NOGENERAL FALSE or TRUE <node>, <QUEUE-name>
NOSYSTEM FALSE or TRUE <node>, <QUEUE-name>
NOUIC FALSE or TRUE <node>, <QUEUE-name>
Practical considerations In cases where existing use of UIC identifiers is pervasive temporary customization might be required.

CHECKPOINT

Ensure that use of queue checkpoint capability conform to policy.

Violation reports

Constraint Nature of the violation
BATPROHIB Batch job was submitted /RESTART in violation of policy
BATREQUIRE Batch job was submitted /NORESTART in violation of policy
PRIPROHIB Print job was submitted /RESTART in violation of policy
PRIREQUIRE Print job was submitted /NORESTART in violation of policy

Description

This element supports tests regarding whether the /RESTART capability is specified for jobs in print queues (where it is the VMS default) and batch queues (where it is not the VMS default).
Default policy Print jobs just be submitted /RESTART. Customizing Use the tests for this element to ensure batch and print operations are carried out in a reliable fashion. selector

Limits

Constraint Value Default
BATPROHIB FALSE or TRUE FALSE
BATREQUIRE FALSE or TRUE FALSE
PRIPROHIB FALSE or TRUE FALSE
PRIREQUIRE FALSE or TRUE TRUE

Exemptions

Constraint Value Parameters
BATPROHIB FALSE or TRUE <node>, <QUEUE-name>
BATREQUIRE FALSE or TRUE <node>, <QUEUE-name>
PRIPROHIB FALSE or TRUE <node>, <QUEUE-name>
PRIREQUIRE FALSE or TRUE <node>, <QUEUE-name>
Practical considerations This element does not consider the issue of whether batch jobs are making efficient use of the BATCH$RESTART capability, since that requires analysis of individual batch jobs.

MANAGER

Ensure that use of queue manager conform to policy.

Violation reports

Constraint Nature of the violation
PROHIBITED Queue Manager is running in violation of policy
REQUIRED Queue Manager is not running in violation of policy

Description

This element supports tests regarding whether the queue manager is running.
Default policy The Queue Manager must be running. Customizing Preventing use of the Queue Manager considerably restricts the ability to run reliable assured backups. Consider protecting queues as an alternative. selector

Limits

Constraint Value Default
PROHIBITED FALSE or TRUE FALSE
REQUIRED FALSE or TRUE TRUE

Exemptions

Constraint Value Parameters
PROHIBITED FALSE or TRUE <node>, <QUEUE-name>
REQUIRED FALSE or TRUE <node>, <QUEUE-name>
Practical considerations Most installations run the Queue Manager.

OPRMARKING

Ensure that use of mandatory print queue marking conform to policy.

Violation reports

Constraint Nature of the violation
PROHIBITED Output execution queue outputs a description in violation of policy
REQUIRED Output execution queue does not output a description in violation of policy
CONTAINS Output execution queue description does not include text required by policy

Description

This element supports tests regarding whether print queues include mandatory descriptions as specified by the queue initialization command /SEPARATE=(BURST,FLAG,TRAILER)/DESCRIPTION="description".
Default policy Mandatory print queue marking is not required. Customizing Use this element to verify that output markings restricting distribution of printouts are configured. selector

Limits

Constraint Value Default
PROHIBITED FALSE or TRUE FALSE
REQUIRED FALSE or TRUE FALSE
CONTAINS text null string

Exemptions

Constraint Value Parameters
PROHIBITED FALSE or TRUE <node>, <QUEUE-name>
REQUIRED FALSE or TRUE <node>, <QUEUE-name>
CONTAINS text <node>, <QUEUE-name>
Practical considerations This element pertains to operator-imposed markings that cannot be bypassed by individual users.

OWNER

Ensure that ownership of queues conforms to policy.

Violation reports

Constraint Nature of the violation
WRONG Queue owner is not as specified

Description

If an individual user account gains ownership of a queue, it can be used to interfere with services to other users.

The purpose of this test is to ensure that the proper owner retains ownership of QUEUEs that are not in use. This test checks the ownership of any QUEUE not currently in use and reports any instance in which the owner is not the proper owner.

For limits only (not exemptions), owner matching string of [SYSTEM] will match (as a special case) against UIC's which are represented as [1,4] (due, for instance, to absence of a Rights Database (RIGHTSLIST.DAT)).

Default policy Every queue must be owned by the system. Customizing An alternative owner can be specified for any QUEUE by setting an exemption. It is also possible to change the standard owner to be some account other than the system, by changing the limit for this test. selector

Limits

Constraint Value Default
WRONG Identifier [SYSTEM]

Exemptions

Constraint Value Parameters
WRONG Identifier <node>, <QUEUE-name>
Practical considerations QUEUE ownership and protection must be considered jointly.

PROTECTION

Ensure that each QUEUE's protection setting meets the minimum setting defined by policy.

Violation reports

Constraint Nature of the violation
ABSOLUTLO Access is narrower than permitted by policy
ABSOLUTHI Access is wider than permitted by policy
NOSYSOWNER Queue is owned by a system UIC in violation of policy
PERCENTLO Fewer users can access than permitted by policy
PERCENTHI More users can access than permitted by policy
SYSOWNER Queue is not owned by a system UIC in violation of policy

Description

Under VMS, a protection setting can be applied to a queue in the same way that it can be applied to files. This allows a given user (or group of users) to have exclusive access to a given disk, for example. Conversely, it can be set to keep a QUEUE open for access by all users, or to limit them to read access.

The purpose of this test is to ensure that the protection settings for QUEUEs remain at the levels established by policy.

The ABSOLUTLO and ABSOLUTHI tests measure the UIC-based protection mask directly. The PERCENTLO and PERCENTHI tests measure the result of protection (including ACL protection) in terms of the percentage of usernames given access.

Default policy Queues have a system owner.

The most permissive protection allowed for a queue gives 100 percent of the users Read and Submit access, but only 10 percent of the users more powerful access. Customizing The default limit values for these tests leave queue protection "wide open", so changes should be made to obtain any value from this test. selector Limits for constraints PERCENTLO and PERCENTHI can take a selector consisting of a VMS QUEUE access type: READ, WRITE, LOGICAL, PHYSICAL or CONTROL. If no selector is specified, customization commands apply to all possible selector values.

Limits

Constraint Value Default
ABSOLUTLO Any Protection (S:M,O:D,G:R,W:S)
ABSOLUTHI Any Protection (S:RSMD,O:RSMD,G:RSMD,W:RSMD)
NOSYSOWNER FALSE or TRUE FALSE
PERCENTLO 0-100 0
PERCENTHI 0-100 R:100,S:100,M:10,D:10,C:10
SYSOWNER FALSE or TRUE TRUE

Exemptions

Constraint Value Parameters
ABSOLUTLO Any Protection <node>, <QUEUE-name>
ABSOLUTHI Any Protection <node>, <QUEUE-name>
NOSYSOWNER FALSE or TRUE <node>,<filespec>
PERCENTLO 0-100 <node>, <QUEUE-name>
PERCENTHI 0-100 <node>, <QUEUE-name>
SYSOWNER FALSE or TRUE <node>,<filespec>
Practical considerations Private queue ownership is a powerful mechanism to allow project operators without giving full OPER privilege.


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