HP OpenVMS Systems

HP Advanced Server for OpenVMS
Server Administrator's Guide

To secure shared directories effectively, keep the following in mind:

• Share permissions apply to network users, not OpenVMS users. However, network user accounts can be host mapped to OpenVMS user accounts, providing access to OpenVMS resources for network users based on their OpenVMS user accounts.
• Share permissions apply to all files and subdirectories created in the shared directory. You can set access permissions for specific files and subdirectories in the share. For more information, see Section 4.3.5.3, Inheriting Permissions. Note that you can restrict user access to specific files and subdirectories in a share (using the SET FILE command), or you can restrict user access at the share level (using the ADD SHARE/PERMISSIONS= or MODIFY SHARE/PERMISSIONS= command). For example, you can restrict a user to READ access to the contents of a share by modifying the permissions for that share. This would override any other access previously granted the user to the contents of that share.

Table 4-7, Share Permissions, shows permissions available for shares and the actions available to users for each permission.

You can share an existing OpenVMS directory. When you share a directory, you specify its location on the server, including the disk device, the directory name, and the name for the share. The following example shows how to share a directory on the server:

Use the ADD SHARE/DIRECTORY command. For example:

LANDOFOZ\\TINMAN> ADD SHARE/DIRECTORY RAINBOW USER1:[SHARED] -
_LANDOFOZ\\TINMAN> /HOST_ATTRIBUTES=(RMS_FORMAT=STREAM)
%PWRK-S-SHAREADD, share "RAINBOW" added on server "TINMAN"

This command adds a directory share named RAINBOW for the directory USER1:[SHARED]. Files created in this directory will be RMS stream-format files. Because the /PERMISSIONS qualifier is not included on the command line, the new share is available to all network users.

4.3.2.4 Creating a Personal Share

The Advanced Server allows you to set up personal shares, which are typically used for sharing a user's OpenVMS login directory. Personal shares are unique in that they are hidden (they will not appear in the list of shares users can display, such as in Network Neighborhood), but the names of personal shares do not end with a dollar sign ($). Thus, when users want to map a drive to their OpenVMS login directory, they specify a personal share name (typically the same as their user name) without having to include a dollar sign in the share name.

A personal share typically points to the root directory of a user's OpenVMS account. For example, network user SCARECROW has a personal share that is mapped to the OpenVMS directory [STRAWMAN] on server TINMAN. If you display the personal shares on TINMAN, the following information appears:

LANDOFOZ\\TINMAN> SHOW SHARES/TYPE=PERSONAL

Shared resources on server "TINMAN":

Name          Type       Description
------------  ---------  -------------------------------------
STRAWMAN      Personal

  Total of 1 share

STRAWMAN, the host mapped OpenVMS account, has a login directory defined in the UAF record; for example: DUA1:[000000]STRAWMAN.DIR, or DUA1:[STRAWMAN]. You can use the AUTHORIZE utility to display a system's UAF records. For example:

$ MCR AUTHORIZE
UAF> SHOW STRAWMAN

Username:     STRAWMAN           Owner: SYSTEM MANAGER
Account:      SYSTEM                    UIC: [360,44] ([PCSA,STRAWMAN])
CLI:          DCL                       Table: DCLTABLES
Default:      DUA1:[STRAWMAN]
LGICMD: LOGIN
   .
   .
   .

Only users in the Administrators group can display and access all the personal shares on a server.

Follow these steps to create a personal share:

1. Add a share using the ADD SHARE/PERSONAL command.
2. Use the SHOW SHARES/TYPE=PERSONAL command to display the share. Include the /FULL qualifier to display the path and permissions. For example:

LANDOFOZ\\TINMAN> ADD SHARE GREATOZ USER1:[USERS] -
_LANDOFOZ\\TINMAN> /PERSONAL/NOPERMISSIONS/PERMISSIONS=(LION=FULL)
%PWRK-S-SHAREADD, share "GREATOZ" added on server "TINMAN"

LANDOFOZ\\TINMAN> SHOW SHARES/TYPE=PERSONAL/FULL

Shared resources on server "TINMAN":

Name          Type       Description
------------  ---------  ------------------------------------------
GREATOZ       Personal
    Path: USER1:[USERS]
    Connections:  Current: 0, Maximum: No limit
    RMS file format: Stream
    Directory Permissions: System: RWED, Owner: RWED, Group: RWED, World: RE
    File Permissions: System: RWD, Owner: RWD, Group: RWD, World: R
    Share Permissions:
        LION                            Full Control
     Total of 1 share

LANDOFOZ\\TINMAN>

After the personal share is created, you can set up the associated directory as the user's home directory. The home directory contains files and programs for the user, and is automatically accessible when the user logs on to the network. For information about setting up home directories, see Section 3.1.10, Specifying Home Directories.

4.3.2.5 Stopping Directory Sharing

You may need to stop sharing a directory when the directory is no longer being used and you want to delete it; for example, when a project requiring the use of shared files is completed. Advise users when you are planning to stop sharing a directory.

For example, to stop sharing the directory GREATOZ, use the ADMINISTER command REMOVE SHARE, as follows:

LANDOFOZ\\TINMAN> REMOVE SHARE GREATOZ/NOCONFIRM
%PWRK-S-SHAREREM, share "GREATOZ" removed from server "TINMAN"

LANDOFOZ\\TINMAN>

This example removes the share named GREATOZ from the server named TINMAN; no confirmation is required. When you stop sharing a directory, the share name is removed from the share database and no longer appears on the list of available shares. However, the directory and its files are not deleted.

4.3.3 Displaying Information About Shares

You can use the SHOW SHARES command to display the shares provided by a server and to see which shares are available to the network. Before sharing a new directory from the server, first check which shares are currently available.

The following example shows how to display the shared directories for your server:

LANDOFOZ\\TINMAN> SHOW SHARES

Shared resources on server "TINMAN":

Name          Type       Description
------------  ---------  ---------------------------------------
NETLOGON      Directory  Logon Scripts Directory
PWLIC         Directory  PATHWORKS Client License Sftwr
PWLICENSE     Directory  PATHWORKS Client License Sftwr
PWUTIL        Directory  Adv. Srv. Client-based Utilities
USERS         Directory  Users Directory

  Total of 5 shares

LANDOFOZ\\TINMAN>

The default display does not show administrative shares and personal shares.

You can display information about administrative shares (those that end with $) using the SHOW SHARES/HIDDEN command, as described in Section 4.2, Administrative Shares.

You can display information about personal shares using the SHOW SHARES/TYPE=PERSONAL command.

You can display information about all shares using the SHOW SHARE/TYPE=ALL command.

4.3.3.1 Displaying Information About a Specific Share

You can display information about any share, regardless of the type of share, by specifying the share name, as in the following example:

LANDOFOZ\\TINMAN> SHOW SHARES RAINBOW

Shared resources on server "TINMAN":

Name          Type       Description
------------  ---------  --------------------
RAINBOW       Personal

  Total of 1 share

To display share permissions, use the SHOW SHARES command with the /PERMISSIONS qualifier. For example:

LANDOFOZ\\TINMAN> SHOW SHARES/PERMISSIONS
Shared resources on server "TINMAN":
Name          Type       Description
------------  ---------  --------------------------------------------------
DICK          Printer    Dick's print share
    Share Permissions:
        Everyone                        Full Control
NETLOGON      Directory  Logon Scripts Directory
    Share Permissions:
        Everyone                        Read
PATHWORKS     Directory
    Share Permissions:
        Everyone                        Full Control
PWLIC         Directory  PATHWORKS Client License Sftwr
    Share Permissions:
        Administrators                  Full Control
        Everyone                        Read
PWLICENSE     Directory  PATHWORKS Client License Sftwr
    Share Permissions:
        Administrators                  Full Control
        Everyone                        Read
PWUTIL        Directory  Adv. Srv. Client-based Utilities
    Share Permissions:
        Everyone                        Read
USERS         Directory  Users Directory
    Share Permissions:
        Everyone                        Full Control

  Total of 7 shares

LANDOFOZ\\TINMAN>

You can change the properties of an existing share using the MODIFY SHARE command. You can change the following share properties:

• Number of users allowed to connect to a shared directory
• Shared directory's description
• Share permissions

To change the properties of a shared directory, you must be logged on as a member of the Administrators or Server Operators group.

The following example shows how to use the MODIFY SHARE command to add permissions on an existing directory share called GREATOZ and to grant READ access to the user SCARECROW:

LANDOFOZ\\TINMAN> MODIFY SHARE GREATOZ/PERMISSIONS=(SCARECROW=READ)
%PWRK-S-SHAREMOD, share "GREATOZ" modified on server "TINMAN"

LANDOFOZ\\TINMAN>

Users and groups can be granted or denied access to specific files and subdirectories in a shared directory. A user denied access to a file or directory, either individually or as a member of a group, can connect to the share but cannot perform any operations with the files and directories in the share. You can grant specific unique access permissions for files and directories in shares that users can access. Once a user connects to the resource, the file and directory access permissions control the operations that the user can perform. For information about specifying share permissions, see Section 4.3.2.2, Planning Share Permissions.

You can enable users to set access permissions on their own files and directories. These users can then control whether other users can read, write, or modify files in that directory. To enable users to set access permissions, give them full control using the SET FILE command.

4.3.5.1 File and Directory Access Permissions

Table 4-8, Directory Access Permissions and Actions on Directories, lists the types of access users can have and the permissions to set on directories.

Table 4-9, Directory Access Permissions and Actions on Files, lists the types of access users can have to files and the permissions to set on them.

By default, anyone with a valid network user name and password can log on to a server and connect to a share on that server. However, a user must have the requisite permissions to access the directories and files in the share. You use the SET FILE/PERMISSIONS command to set permissions on a shared directory. You may need to change access permissions if users cannot access the directories or files they need, or if unauthorized users can access them. For information about how a file or directory that does not have explicit permissions inherits the permissions, see Section 4.1.3.1, Inheritance of Directory Permissions, and Section 4.3.5.3, Inheriting Permissions.

Permissions for disk resources are stored on the disk with each resource as an OpenVMS access control list (ACL). Thus, resource permissions are backed up by the OpenVMS Backup utility.

4.3.5.3 Inheriting Permissions

As you create subdirectories and files in shared directories that have existing permissions, those permissions are automatically propagated to the new subdirectories and files. (This assumes the default for the STORE_SECURITY_ACES is in effect; see Section 4.1.3.6, Streamlining Security Information Storage and Lookups, for more information.) However, if you decide to share a directory that contains existing subdirectories and files, the permissions you assign to the new share are not propagated to its subdirectories and files. You can either explicitly set permissions for each subdirectory and file, or you allow their permissions to be inherited.

4.3.6 Specifying File and Directory Access Permissions

When sharing a directory on a server, you specify the name of the groups and users who can access the share, its subdirectories, and its files, and the permissions each group or user has for the share. After the share has been created, you can modify the permissions on the files and directories in the share. The following example shows how to use the SET FILE/PERMISSIONS command to modify permissions. In this example, the command specifies the access permissions for all files with the .C extension in the directory CURTAIN in share GREATOZ.

LANDOFOZ\\TINMAN> SET FILE GREATOZ\CURTAIN\*.C -
_LANDOFOZ\\TINMAN> MUNCHKINS/PERMISSIONS=READ -
_LANDOFOZ\\TINMAN> SCARECROW/PERMISSIONS=FULL_CONTROL
%PWRK-S-FILEMOD, "GREATOZ\CURTAIN\FILE1.C" modified on server "TINMAN"

%PWRK-S-FILESMODIFIED, total of 1 file modified
LANDOFOZ\\TINMAN>

As a result, the following permissions are set:

• Group MUNCHKINS has READ access
• User SCARECROW has FULL access