You can use Oracle Data Encryption with other Oracle features, such as Oracle Data Guard or Oracle Real Application Clusters.
How Transparent Data Encryption Works with Export and Import Operations
Oracle Data Pump can export and import tables that contain encrypted columns, as well as encrypt entire dump sets.
About Exporting and Importing Encrypted Data
You can use Oracle Data Pump to export and import tables that have encrypted columns.
For both software and hardware keystores, the following points are important when you must export tables containing encrypted columns:
Sensitive data should remain unintelligible during transport.
Authorized users should be able to decrypt the data after it is imported at the destination.
When you use Oracle Data Pump to export and import tables containing encrypted columns, it uses the
ENCRYPTION parameter to enable encryption of data in dump file sets. The
ENCRYPTION parameter allows the following values:
ENCRYPTED_COLUMNS_ONLY: Writes encrypted columns to the dump file set in encrypted format
DATA_ONLY: Writes all of the data to the dump file set in encrypted format
METADATA_ONLY: Writes all of the metadata to the dump file set in encrypted format
ALL: Writes all of the data and metadata to the dump file set in encrypted format
NONE: Does not use encryption for dump file sets
Exporting and Importing Tables with Encrypted Columns
You can export and import tables with encrypted columns using the
Ensure that the keystore is open before you attempt to export tables containing encrypted columns.
In a multitenant environment, if you are exporting data in a pluggable database (PDB), then ensure that the wallet is open in the PDB. If you are exporting into the root, then ensure that the wallet is open in the root.
To find if the keystore is open, query the
STATUScolumn of the
V$ENCRYPTION_WALLETview. If you must open the keystore, then run the following SQL statement:
ADMINISTER KEY MANAGEMENT SET KEYSTORE OPEN IDENTIFIED BY software_keystore_password [CONTAINER = ALL | CURRENT];
software_keystore_passwordsetting is the password for the keystore. The keystore must be open because the encrypted columns must be decrypted using the TDE table keys, which requires access to the TDE master encryption key. The columns are reencrypted using a password, before they are exported.
EXPDPcommand, using the
ENCRYPTION_PASSWORDparameter to specify a password that is used to encrypt column data in the export dump file set.
The following example exports the
ENCRYPTION_PWD_PROMPT = YESsetting enables you to prompt for the password interactively, which is a recommended security practice.
expdp hr TABLES=employee_data DIRECTORY=dpump_dir DUMPFILE=dpcd2be1.dmp ENCRYPTION=ENCRYPTED_COLUMNS_ONLY ENCRYPTION_PWD_PROMPT = YES Password: password_for_hr
To import the exported data into the target database, ensure that you specify the same password that you used for the export operation, as set by the
The password is used to decrypt the data. Data is reencrypted with the new TDE table keys generated in the target database. The target database must have the keystore open to access the TDE master encryption key. The following example imports the
impdp hr TABLES=employee_data DIRECTORY=dpump_dir DUMPFILE=dpcd2be1.dmp ENCRYPTION_PWD_PROMPT = YES Password: password_for_hr
Using Oracle Data Pump to Encrypt Entire Dump Sets
Oracle Data Pump can encrypt entire dump sets, not just Transparent Data Encryption columns.
While importing, you can use either the password or the keystore TDE master encryption key to decrypt the data. If the password is not supplied, then the TDE master encryption key in the keystore is used to decrypt the data. The keystore must be present and open at the target database. The open keystore is also required to reencrypt column encryption data at the target database.
You can use the
ENCRYPTION_MODE=TRANSPARENT setting to transparently encrypt the dump file set with the TDE master encryption key stored in the keystore. A password is not required in this case. The keystore must be present and open at the target database, and it must contain the TDE master encryption key from the source database for a successful decryption of column encryption metadata during an import operation.
The open keystore is also required to reencrypt column encryption metadata at the target database. If a keystore already exists on the target database, then you can export the current TDE master encryption key from the keystore of the source database and import it into the keystore of the target database.
ENCRYPTION_MODEparameter to specify the encryption mode.
ENCRYPTION_MODE=DUALencrypts the dump set using the TDE master encryption key stored in the keystore and the password provided.
For example, to use dual encryption mode to export encrypted data:
expdp hr DIRECTORY=dpump_dir1 DUMPFILE=hr_enc.dmp ENCRYPTION=all ENCRYPTION_PASSWORD=encryption_password ENCRYPTION_PWD_PROMPT=yes ENCRYPTION_ALGORITHM=AES256 ENCRYPTION_MODE=dual Password: password_for_hr Encryption Password: password_for_encryption
Using Oracle Data Pump with Encrypted Data Dictionary Data
Oracle Data Pump operations provide protections for encrypted passwords and other encrypted data.
When you enable the encryption of fixed-user database passwords in a source database, then an Oracle Data Pump export operation dump stores a known invalid password for the database link password. This password is in place instead of the encrypted password that the export operation extracts from the database. An
ORA-39395: Warning: object <database link name> requires password reset after import warning message is displayed as a result. If you import data into an Oracle Database 18c or later database, then this same warning appears when the database link object with its invalid password is created in the target database. When this happens, you must reset the database link password, as follows:
ALTER DATABASE LINK database_link_name CONNECT TO schema_name IDENTIFIED BY password;
To find information about the database link, you can query the
V$DBLINK dynamic view.
When the encryption of fixed-user database passwords has been disabled in a source database, then there are no changes to Data Pump. The obfuscated database link passwords are exported and imported as in previous releases.
In this case, Oracle recommends the following:
ENCRYPTION_PASSWORDparameter on the
expdpcommand so that you can further protect the obfuscated database link passwords.
YESso that the password can be entered interactively from a prompt, instead of being echoed on the screen.
ENCRYPTION_PASSWORD and the
ENCRYPTION_PWD_PROMPT parameters are available in import operations.
ENCRYPTION_PWD_PROMPT is only available with the
impdp command-line clients, whereas
ENCRYPTION_PASSWORD is available in both the command-line clients and the
DBMS_DATAPUMP PL/SQL package.
During an import operation, whether the keystore is open or closed affects the behavior of whether or not an encryption password must be provided. If the keystore was open during the export operation and you provided an encryption password, then you do not need to provide the password during the import operation. If the keystore is closed during the export operation, then you must provide the password during the import operation.
How Transparent Data Encryption Works with Oracle Data Guard
For both software keystores and hardware keystores, Oracle Data Guard supports Transparent Data Encryption (TDE).
If the primary database uses TDE, then each standby database in a Data Guard configuration must have a copy of the encryption keystore from the primary database. If the primary database uses TDE, then each standby database in a Data Guard configuration must have an encryption keystore with the keystore from the primary database merged into it. If you reset the TDE master encryption key in the primary database, then you must merge the keystore on the primary database that contains the TDE master encryption key to each standby database.
Note the following:
Encrypted data in log files remains encrypted when data is transferred to the standby database. Encrypted data also stays encrypted during transit.
TDE works with SQL*Loader direct path loads. The data loaded into encrypted columns is transparently encrypted during the direct path load.
Materialized views work with TDE tablespace encryption. You can create both materialized views and materialized view logs in encrypted tablespaces. Materialized views also work with TDE column encryption.
How Transparent Data Encryption Works with Oracle Real Application Clusters
Oracle RAC nodes can share both a software keystore and a hardware security module.
About Using Transparent Data Encryption with Oracle Real Application Clusters
Oracle Database enables Oracle RAC nodes to share a software keystore.
A configuration with a hardware security module uses a network connection from each instance of the database to the shared hardware security module. This eliminates the need to manually copy the software keystore to each of the other nodes in the cluster. Oracle recommends that you create the software keystore on a shared file system. This enables all of the instances to access the same shared software keystore. If you configure Oracle RAC to use Automatic Storage Management (ASM), then store the keystore on the ASM disk group.
For a hardware security module based configuration, configure the database instance on each Oracle RAC node to connect to the shared hardware security module. Thus, all instances of the database have access to the hardware security module.
Keystore operations that must be performed on all of the instances (such as opening or closing the keystore, or rekeying the TDE master encryption key) can be issued on any one Oracle RAC instance. Internally, the Oracle database takes care of synchronizing the keystore context on each Oracle RAC node, so that the effect of the keystore operation is visible to all of the other Oracle RAC instances in the cluster. This means that when you open the keystore on one instance, then it also opens for each of the other Oracle RAC instances. Similarly, when a TDE master encryption key rekey operation takes place, the new key becomes available to each of the Oracle RAC instances. This means that when you open the keystore on one database instance, it opens for each of the other Oracle RAC instances. You can perform other keystore operations, such as exporting TDE master encryption keys, rotating the keystore password, merging keystores, or backing up keystores, from a single instance only.
When using a shared file system, ensure that the
WALLET_LOCATION parameter setting in the
sqlnet.ora file for all of the Oracle RAC instances point to the same shared software keystore location. You also must ensure security of the shared software keystore by assigning the appropriate directory permissions.
Using a Non-Shared File System to Store a Software Keystore in Oracle RAC
If you do not use a shared file system to store the software keystore, then you must copy the keystore to the associated nodes.
Log in to the instance of the database as a user who has been granted the
ADMINISTER KEY MANAGEMENTor
In a multitenant environment, log in to the root or the appropriate PDB. For example:
sqlplus sec_admin@hrpdb as syskm Enter password: password Connected.
Reset the TDE master encryption key on the first Oracle Real Application Clusters (Oracle RAC) node.
For example, for column encryption:
ADMINISTER KEY MANAGEMENT SET KEY IDENTIFIED BY keystore_password WITH BACKUP USING 'emp_key_backup';
Copy the keystore file with the new TDE master encryption key from the first node to all of the other nodes.
To find the keystore file location, query the
WRL_PARAMETERcolumn in the
V$ENCRYPTION_WALLETview. To find the
WRL_PARAMETERsettings for all of the database instances, query the
Close and then reopen the keystore on any node.
If you are using a multitenant container database (CDB), then run the following statement in the root:
ADMINISTER KEY MANAGEMENT SET KEYSTORE OPEN FORCE KEYSTORE IDENTIFIED BY software_keystore_password [CONTAINER = ALL | CURRENT];
Any keystore operation, such as opening or closing the keystore, performed on any one Oracle RAC instance applies to all other Oracle RAC instances. This is true even if you are not using a shared file system.
All of the Oracle RAC nodes are now configured to use the new TDE master encryption key.
How Transparent Data Encryption Works with SecureFiles
SecureFiles, which stores LOBS, has three features: compression, deduplication, and encryption.
About Transparent Data Encryption and SecureFiles
SecureFiles encryption uses TDE to provide the encryption facility for LOBs.
When you create or alter tables, you can specify the SecureFiles encryption or LOB columns that must use the SecureFiles storage. You can enable the encryption for a LOB column by either using the current Transparent Data Encryption (TDE) syntax or by using the
ENCRYPT clause as part of the LOB parameters for the LOB column. The
DECRYPT option in the current syntax or the LOB parameters turn off encryption.
Example: Creating a SecureFiles LOB with a Specific Encryption Algorithm
CREATE TABLE statement can create a SecureFiles LOB with encryption specified.
Example 8-1 shows how to create a SecureFiles LOB in a
CREATE TABLE statement.
Example 8-1 Creating a SecureFiles LOB with a Specific Encryption Algorithm
CREATE TABLE table1 ( a BLOB ENCRYPT USING 'AES256') LOB(a) STORE AS SECUREFILE ( CACHE );
Example: Creating a SecureFiles LOB with a Column Password Specified
CREATE TABLE statement can create a SecureFiles LOB with a column password.
Example 8-2 shows an example of creating a SecureFiles LOB that uses password protections for the encrypted column.
All of the LOBS in the LOB column are encrypted with the same encryption specification.
Example 8-2 Creating a SecureFiles LOB with a Column Password Specified
CREATE TABLE table1 (a VARCHAR2(20), b BLOB) LOB(b) STORE AS SECUREFILE ( CACHE ENCRYPT USING 'AES192' IDENTIFIED BY password );
How Transparent Data Encryption Works with Oracle Call Interface
Transparent Data Encryption does not have any effect on the operation of Oracle Call Interface (OCI).
For most practical purposes, TDE is transparent to OCI except for the row shipping feature. You cannot use the OCI row shipping feature with TDE because the key to make the row usable is not available at the receipt-point.
How Transparent Data Encryption Works with Editions
Transparent Data Encryption does not have any effect on the Editions feature of Oracle Database.
For most practical purposes, TDE is transparent to Editions. Tables are always noneditioned objects. TDE Column Encryption encrypts columns of the table. Editions are not affected by TDE tablespace encryption.
Configuring Transparent Data Encryption to Work in a Multidatabase Environment
Each Oracle database on the same server (such as databases sharing the same Oracle binary but using different data files) must access its own TDE keystore.
Keystores are not designed to be shared among databases. By design, there must be one keystore per database. You cannot use the same keystore for more than one database.
To configure the
sqlnet.orafile for a multidatabase environment, use one of the following options:
Option 1: If the databases share the same Oracle home, then keep the
sqlnet.orafile in the default location, which is in the
In this case, it is ideal to use the default location. Ensure that the
sqlnet.orafile has no
ENCRYPTION_WALLET_LOCATIONentries. Transparent Data Encryption accesses the keystore from the default
sqlnet.oralocation if these two entries are not in the
Option 2: If Option 1 is not feasible for your site, then you can specify the keystore location as follows. The
WALLET_ROOTinitialization parameter is shared by all PDBs, but each CDB (or standalone database) must have its own separate
WALLET_ROOT = /home/oracle/db_unique_name/wallet/
Option 3: If Options 1 and 2 are not feasible, then use separate
sqlnet.orafiles, one for each database. Ensure that you correctly set the
TNS_ADMINenvironment variable to point to the correct database configuration.
Using a keystore from another database can cause partial or complete data loss.