Policy and GuardPoint Management
You can use the same CTE-LDT policies that you use for protecting GuardPoint directories in local file systems and NFS/CIFS shares. The only exception is that for CTE-LDT protected GuardPoints, it only supports backup/ restore of files that do not use Apply Key.
Security Rule Ordering for Polices
If you want to enforce restrictions when guarding NFS shares using an LDT or standard policy with a CBC-CS1 key, note the following:
CipherTrust Transparent Encryption embeds and hides LDT and/or IV (initialization vector) attributes in the first 4K of files for NFS shares guarded with an LDT or standard policy with a CBC-CS1 key. Embedding CipherTrust Transparent Encryption attributes increases the actual file size by 4K, and CTE hides that extra 4K when reporting the file size. The exception to this is when a backup/restore process reads/writes such files. This requires embedded attributes to be read/restored by the backup/restore process. In such cases, CipherTrust Transparent Encryption does not hide the 4K attribute space in the file. The backup user/process views the actual file size. Non-backup users/applications view the file size as less than 4K.
If you want a security rule to enforce restricted access for reading file level attributes on such GuardPoints, you must specify the Apply Key effect. Alternatively, you can place the security rule that is enforcing the restricted access after the rule granting read/write access. This avoids application failure if the Apply key effect is not desired. For example, the order of the two rules in a policy that does not hide the user user-name would be:
-
Security Rule n
Rule Value User <user-name>
Action Read-file-attribute and/or Read directory Effect permit -
Security Rule n + 1
Rule Value User <user-name>
Action all_ops Effect permit, apply-key
Assuming <user-name>
is not affiliated with backup/restore operations, <user-name>
would view the actual file size which is 4K larger than the size of the user data in the file. The returned file size can result in failure when user-name attempts to read/write files. By reordering rules n and n + 1, <user-name>
will view the correct size hiding the 4K attribute space in the target file.
For more information, see Adding Security Rules in the CipherTrust Manager documentation.