HP OpenVMS Guide to System Security

Security for the User

Protecting Data

Controlling Access with Protection Codes

Auditing Protected Objects

Understanding Privilegesand Control Access  

How Privileges Affect Protection Mechanisms  

Security administrators can assign privileges to users whenthey create or modify user accounts. The system privileges READALLand BYPASS affect user access, regardless of the access dictatedby an ACL for the object or by other elements in its security profile.The privileges SYSPRV and GRPPRV are controlled through the systemcategory of the protection code. The privileges have the followingmeanings:

BYPASS	A user with BYPASS privilegereceives all types of access to the object, regardless of its protection.
GRPPRV	A user with GRPPRV privilegewhose UIC group matches the group of the owner of the object receivesthe same access accorded to users in the system category. Thus,the user with GRPPRV privilege is able to manage any of the group'sobjects.
READALL	A user with READALL privilegereceives read access to the object, even if that access is deniedby the ACL and the protection code. In addition, the user can receiveany other access granted through the protection code.
SYSPRV	A user with SYSPRV privilege receivesthe access accorded to users in the system category.

When you define ACLs or protection codes for your objects,remember that users with amplified privileges are entitled to specialaccess to objects throughout the system. For example, there is noway to stop a user with the BYPASS privilege from accessing yourfiles. Users with GRPPRV privilegehave the power to perform many system management functions for othermembers of their UIC group. Protection of your objects dependson the judgment of your security administrator in granting theseprivileges.

Using Control Access to Modify an ObjectProfile  

Any user with control access to an object can change its protectioncode and ACL and thereby gain access to an object. For all objectclasses but files, control access also allows a user to modify theobject's owner. To modify the owner of a file generally requiresprivilege (see Types of Access).

You obtain control access in any of the following ways:

• You hold an identifier to which theobject's ACL gives control access.



• You have the same UIC as the owner of the object.



• You qualify as a member of the system user category,and the object has an owner with a nonzero UIC. For example, youhold GRPPRV (with a matching group UIC) or SYSPRV. (Refer to Controlling Access with Protection Codes for a full descriptionof system users.)



• You hold BYPASS privilege.

Sometimes object classes allow control access through othermeans. Refer to Object-Specific Access Considerations andto the individual descriptions of classes in Descriptions of Object Classes for any special conditions that may apply.

Object-Specific Access Considerations  

For some objects, access can be granted either by a specialprivilege (beyond those listed in How Privileges Affect Protection Mechanisms) or by an all-inclusive type of access. This isparticularly true of a queue. A user with operator (OPER) privilegeis granted all types of access to a queue. A user with manage accessimplicitly possesses the three other types of queue access: read,submit, and delete. Descriptions of Object Classes listseach object class with its access types and meanings and any specialprivilege.

Controlling Access with Protection Codes

Auditing Protected Objects