Rekeying

You can change (rekey) a master key and table keys. You cannot rekey tablespace keys.

Getting ready

It is assumed that a keystore is opened and a master key is created.

How to do it...

1. Connect to the database as a user who has administer key privilege or SYSKM privilege (for example, maja):

   $ sqlplus maja
   

2. To rekey a table (for example, the oe.customer) using a different encryption algorithm (for example, AES128), execute the following statement:

   

   Figure 24 - Rekeying a table key

3. Change a master key by executing the following statement (in our example, keystore_password is welcome1):

   SQL> ADMINISTER KEY MANAGEMENT SET KEY IDENTIFIED BY
   keystore_password
   WITH BACKUP;
   

   

   Figure 25 - Rekeying a master key

How it works...

When you changed a table key, in step 2, all encrypted data in the oe.customers table were decrypted and then encrypted using the new table key and the new encryption algorithm. If you just want to change key and use the same algorithm as before, syntax for rekeying is...