Solaris Trusted Extensions Administrator's Procedures
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Chapter 6 Users, Rights, and Roles in Trusted Extensions (Overview)

This chapter describes essential decisions that you must make before creating regular users, and provides additional background information for managing user accounts. The chapter assumes that the initial setup team has set up roles and a limited number of user accounts. These users can assume the roles that are used to configure and administer Solaris Trusted Extensions. For details, see Creating Roles and Users in Trusted Extensions in Solaris Trusted Extensions Configuration Guide.

User Security Features in Trusted Extensions

Trusted Extensions software adds the following security features to users, roles, or rights profiles:

  • A user has a label range within which the user can use the system.

  • A role has a label range within which the role can be used to perform administrative tasks.

  • A Trusted Extensions rights profile can include CDE administrative actions. Like commands, actions can have security attributes.

  • Commands and actions in a Trusted Extensions rights profile have a label attribute. The command or action must be performed within a label range, or at a particular label.

  • Trusted Extensions software adds privileges and authorizations to the set of privileges and authorizations that are defined by the Solaris OS.

Administrator Responsibilities for Users

The System Administrator role creates user accounts. The Security Administrator role sets up the security aspects of an account.

If you are using the Sun JavaTM System Directory Server for the LDAP naming service, check that the initial setup team configured the tsol_ldap.tbx toolbox. For the procedure, see Configuring the Solaris Management Console for LDAP (Task Map) in Solaris Trusted Extensions Configuration Guide.

For details on setting up users and roles, see the following:

System Administrator Responsibilities for Users

In Trusted Extensions, the System Administrator role is responsible for determining who can access the system. The system administrator is responsible for the following tasks:

  • Adding and deleting users

  • Adding and deleting roles

  • Modifying user and role configurations, other than security attributes

Security Administrator Responsibilities for Users

In Trusted Extensions, the Security Administrator role is responsible for all security attributes of a user or role. The security administrator is responsible for the following tasks:

  • Assigning and modifying the security attributes of a user, role, or rights profile

  • Creating and modifying rights profiles

  • Assigning rights profiles to a user or role

  • Assigning privileges to a user, role, or rights profile

  • Assigning authorizations to a user, a role, or rights profile

  • Removing privileges from a user, role, or rights profile

  • Removing authorizations from a user, role, or rights profile

Typically, the Security Administrator role creates rights profiles. However, if a profile needs capabilities that the Security Administrator role cannot grant, then superuser or the Primary Administrator role can create the profile.

Before creating a rights profile, the security administrator needs to analyze whether any of the commands or actions in the new profile need privilege or authorization to be successful. The man pages for individual commands list the privileges and authorizations that might be needed. For examples of actions that require privileges and authorizations, see the exec_attr database.

Decisions to Make Before Creating Users in Trusted Extensions

The following decisions affect what users are able to do in Trusted Extensions and how much effort is required. Some decisions are the same as the decisions that you would make when installing the Solaris OS. However, decisions that are specific to Trusted Extensions can affect site security and ease of use.

Default User Security Attributes in Trusted Extensions

Settings in the label_encodings and the policy.conf files together define default security attributes for user accounts. The values that you explicitly set for a user override these system values. Some values that are set in these files also apply to role accounts. For security attributes that you can explicitly set, see Configurable User Attributes in Trusted Extensions.

label_encodings File Defaults

The label_encodings file defines a user's minimum label, clearance, and default label view. For details about the file, see the label_encodings(4) man page. Your site's label_encodings file was installed by your initial setup team. Their decisions were based on Devising a Label Strategy in Solaris Trusted Extensions Configuration Guide, and examples from Solaris Trusted Extensions Label Administration.

Label values that the security administrator explicitly sets for individual users in the Solaris Management Console are derived from the label_encodings file. Explicitly set values override the values in the label_encodings file.

policy.conf File Defaults in Trusted Extensions

The Solaris /etc/security/policy.conf file contains the default security settings for the system. Trusted Extensions adds two keywords to this file. You can add these keyword-value pairs to the file if you want to change the system-wide value. These keywords are enforced by Trusted CDE.

Table 6–1 Trusted Extensions Security Defaults in policy.conf File

Keyword

Default Value

Possible Values

Notes

IDLECMD

LOCK

LOCK | LOGOUT

Does not apply to roles.

IDLETIME

30

0 to 120 minutes

Does not apply to roles.

The authorizations and rights profiles that are defined in the policy.conf file are in addition to any authorizations and profiles that are assigned to individual accounts. For the other fields, the individual user's value overrides the system value.

Planning User Security in Trusted Extensions in Solaris Trusted Extensions Configuration Guide includes a table of every policy.conf keyword. See also the policy.conf(4) man page.

Configurable User Attributes in Trusted Extensions

The Solaris Management Console 2.1 is your tool for creating and modifying user accounts. For users who can log in at more than one label, you might also want to set up .copy_files and .link_files files in each user's minimum–label home directory.

The User Accounts tool in the Solaris Management Console works as it does in the Solaris OS, with two exceptions:

  • Trusted Extensions adds attributes to user accounts.

  • Home directory server access requires administrative attention in Trusted Extensions.

    • You create the home directory server entry the same as you do on a Solaris system.

    • Then, you and the user perform additional steps to mount the home directory at every user label.

As described in How to Add a User With the Solaris Management Console’s Users Tool in System Administration Guide: Basic Administration, a wizard enables you to create user accounts quickly. After using the wizard, you can modify the user's default Trusted Extensions attributes.

For more information about the .copy_files and .link_files files, see .copy_files and .link_files Files.

Security Attributes That Must Be Assigned to Users

The Security Administrator role must specify some security attributes for new users, as the following table shows. For information about the files that contain default values, see Default User Security Attributes in Trusted Extensions.

Table 6–2 Security Attributes That Are Assigned After User Creation

User Attribute

Location of Default Value

Is Action Required

Effect of Action

Password

None

Required

User has password

Roles

None

Optional

User can assume a role

Authorizations

policy.conf file

Optional

User has additional authorizations

Rights Profiles

policy.conf file

Optional

User has additional rights profiles

Labels

label_encodings file

Optional

User has different default label or accreditation range

Privileges

policy.conf file

Optional

User has different set of privileges

Account Usage

policy.conf file

Optional

User has different setting for computer when it is idle

Audit

audit_control file

Optional

User is audited differently from the system audit settings

Security Attribute Assignment to Users in Trusted Extensions

The Security Administrator role assigns security attributes to users in the Solaris Management Console after the user accounts are created. If you have set up correct defaults, your next step is to assign security attributes only for users who need exceptions to the defaults.

When assigning security attributes to users, the security administrator considers the following information:

Assigning Passwords

The Security Administrator role assigns passwords to user accounts after the accounts have been created. After this initial assignment, users can change their passwords.

As in the Solaris OS, users can be forced to change their passwords at regular intervals. The password aging options limit how long any intruder who is able to guess or steal a password could potentially access the system. Also, establishing a minimum length of time to elapse before changing a password prevents a user with a new password from reverting immediately to the old password. For details, see the passwd(1) man page.


Note –

The passwords for users who can assume roles must not be subject to any password aging constraints.


Assigning Roles

A user is not required to have a role. A single user can be assigned more than one role if doing so is consistent with your site's security policy.

Assigning Authorizations

As in the Solaris OS, assigning authorizations directly to a user adds those authorizations to existing authorizations. In Trusted Extensions, you add the authorizations to a rights profile, then assign the profile to the user.

Assigning Rights Profiles

As in the Solaris OS, the order of profiles is important. The profile mechanism uses the first instance of the command or action in an account's profile set.

You can use the sorting order of profiles to your advantage. If you want a command to run with different security attributes from those attributes that are defined for the command in an existing profile, create a new profile with the preferred assignments for the command. Then, insert that new profile before the existing profile.


Note –

Do not assign rights profiles that include administrative actions or administrative commands to a regular user. The profile would not work because a regular user cannot enter the global zone.


Changing Privilege Default

The default privilege set can be too liberal for many sites. To restrict the privilege set for any regular user on a system, change the policy.conf file setting. To change the privilege set for individual users, use the Solaris Management Console. For an example, see How to Restrict a User's Set of Privileges.

Changing Label Defaults

Changing a user's label defaults creates an exception to the user defaults in the label_encodings file.

Changing Audit Defaults

As in the Solaris OS, assigning audit classes to a user creates exceptions to the audit classes that are assigned in the /etc/security/audit_control file on the system. For more information about auditing, see Chapter 18, Trusted Extensions Auditing (Overview).

.copy_files and .link_files Files

In Trusted Extensions, files are automatically copied from the skeleton directory only into the zone that contains the account's minimum label. To ensure that zones at higher labels can use startup files, either the user or the administrator must create the files .copy_files and .link_files.

The Trusted Extensions files .copy_files and .link_files help to automate the copying or linking of startup files into every label of an account's home directory. Whenever a user creates a workspace at a new label, the updatehome command reads the contents of .copy_files and .link_files at the account's minimum label. The command then copies or links every listed file into the higher-labeled workspace.

The .copy_files file is useful when a user wants a slightly different startup file at different labels. Copying is preferred, for example, when users use different mail aliases at different labels. The .link-files file is useful when a startup file should be identical at any label that it is invoked. Linking is preferred, for example, when one printer is used for all labeled print jobs. For example files, see How to Configure Startup Files for Users in Trusted Extensions.

The following lists some startup files that you might want users to be able to link to higher labels or to copy to higher labels:

.acrorc

.login

.signature

.aliases

.mailrc

.soffice

.cshrc

.mime_types

.Xdefaults

.dtprofile

.newsrc

.Xdefaults-hostname

.emacs

.profile