Customizing the Use of Strong Authentication

23 Customizing the Use of Strong Authentication

You can configure multiple authentication methods under Oracle Database native network encryption and strong authentication.

Connecting to a Database Using Strong Authentication
You can use password authentication to connect to a database that is configured to use strong authentication.
Disabling Strong Authentication and Native Network Encryption
You can use Oracle Net Manager to disable strong authentication and native network encryption.
Configuring Multiple Authentication Methods
Many networks use more than one authentication method on a single security server.
Configuring Oracle Database for External Authentication
You can use parameters to configure Oracle Database for network authentication.

Parent topic: Managing Strong Authentication

23.1 Connecting to a Database Using Strong Authentication

You can use password authentication to connect to a database that is configured to use strong authentication.

To connect to an Oracle database server using a user name and password when an Oracle network and strong authentication method has been configured, disable the external authentication.

You must first follow the instructions in Disabling Strong Authentication and Native Network Encryption to disable the external authentication before you can connect to an Oracle Database server using a user name and password when an Oracle network and strong authentication method has been configured.

With the external authentication disabled, connect to the database using the following format:

% sqlplus username@net_service_name
Enter password: password

For example:

% sqlplus hr@emp
Enter password: password

Note:

You can configure multiple authentication methods, including both externally authenticated users and password authenticated users, on a single database.

Parent topic: Customizing the Use of Strong Authentication

23.2 Disabling Strong Authentication and Native Network Encryption

You can use Oracle Net Manager to disable strong authentication and native network encryption.

Start Oracle Net Manager.
- (UNIX) From $ORACLE_HOME/bin, enter the following command at the command line:
```
netmgr
```
- (Windows) Select Start, Programs, Oracle - HOME_NAME, Configuration and Migration Tools, then Net Manager.
Expand Oracle Net Configuration, and from Local, select Profile.
From the Naming list, select Network Security.

The Network Security tabbed window appears.
Select the Authentication tab (which is selected by default).
Sequentially move all authentication methods from the Selected Method list to the Available Methods list by selecting a method and choosing the left arrow [<].

Description of the illustration auth0001.gif
Select the Encryption tab.
Do the following:
- From the Encryption menu, select SERVER.
- Set Encryption Type to rejected.
- In the Encryption Seed field, enter a valid encryption seed if an encryption seed was used.
- Under Select Methods, move any methods to the Available Methods field.
Repeat these steps disable native network encryption for the client, by selecting CLIENT from the Encryption menu.
From the File menu, select Save Network Configuration.
The sqlnet.ora file is updated with the following entries to indicate that strong authentication and native network encryption are disabled:

Strong authentication:
```
SQLNET.AUTHENTICATION_SERVICES = (NONE)
```
For native network encryption, you can set it individually, for the server side and for the client side. The following examples show native network encryption being disabled for both the server and the client:
```
SQLNET.ENCRYPTION_SERVER = REJECTED
SQLNET.ENCRYPTION_CLIENT = REJECTED
```
Be aware that in a multitenant environment, the settings in the sqlnet.ora file apply to all pluggable databases (PDBs).

Related Topics

About the Values for Negotiating Encryption and Integrity

Parent topic: Customizing the Use of Strong Authentication

23.3 Configuring Multiple Authentication Methods

Many networks use more than one authentication method on a single security server.

Accordingly, Oracle Database lets you configure your network so that Oracle clients can use a specific authentication method, and Oracle database servers can accept any method specified.

You can set up multiple authentication methods on both client and server systems either by using Oracle Net Manager, or by using any text editor to modify the sqlnet.ora file. Use Oracle Net Manager to add authentication methods to both clients and servers.

Start Oracle Net Manager.
- (UNIX) From $ORACLE_HOME/bin, enter the following command at the command line:
```
netmgr
```
- (Windows) Select Start, Programs, Oracle - HOME_NAME, Configuration and Migration Tools, then Net Manager.
Expand Oracle Net Configuration, and from Local, select Profile.
From the Naming list, select Network Security.

The Network Security tabbed window appears.
Select the Authentication tab.
Select a method listed in the Available Methods list.
Sequentially move selected methods to the Selected Methods list by clicking the right arrow (>).
Arrange the selected methods in order of desired use.

To do this, select a method in the Selected Methods list, and select Promote or Demote to position it in the list.
From the File menu, select Save Network Configuration.
The sqlnet.ora file is updated with the following entry, listing the selected authentication methods:
```
SQLNET.AUTHENTICATION_SERVICES = (KERBEROS5, RADIUS)
```

Note:

SecurID functionality is available through RADIUS; RADIUS support is built into the RSA ACE/Server.

Related Topics

Configuring RADIUS Authentication

Parent topic: Customizing the Use of Strong Authentication

23.4 Configuring Oracle Database for External Authentication

You can use parameters to configure Oracle Database for network authentication.

Setting the SQLNET.AUTHENTICATION_SERVICES Parameter in sqlnet.ora
The SQLNET.AUTHENTICATION_SERVICES parameter defines the authentication method and version to be used.
Setting OS_AUTHENT_PREFIX to a Null Value
The OS_AUTHENT_PREFIX parameter specifies a prefix that Oracle Database uses to authenticate users who attempt to connect to the server.

Parent topic: Customizing the Use of Strong Authentication

23.4.1 Setting the SQLNET.AUTHENTICATION_SERVICES Parameter in sqlnet.ora

The SQLNET.AUTHENTICATION_SERVICES parameter defines the authentication method and version to be used.

You must set the SQLNET.AUTHENTICATION_SERVICES parameter in the sqlnet.ora file for all clients and servers to enable each to use a supported authentication method.

Set the SQLNET.AUTHENTICATION_SERVICES parameter using the following syntax:
```
SQLNET.AUTHENTICATION_SERVICES=(oracle_authentication_method)
```

For example, for all clients and servers using Kerberos authentication:

SQLNET.AUTHENTICATION_SERVICES=(KERBEROS5)

By default, the sqlnet.ora file is located in the ORACLE_HOME/network/admin directory or in the location set by the TNS_ADMIN environment variable. Ensure that you have properly set the TNS_ADMIN variable to point to the correct sqlnet.ora file.

23.4.2 Setting OS_AUTHENT_PREFIX to a Null Value

The OS_AUTHENT_PREFIX parameter specifies a prefix that Oracle Database uses to authenticate users who attempt to connect to the server.

Authentication service-based user names can be long, and Oracle user names are limited to 30 bytes. Oracle strongly recommends that you set the OS_AUTHENT_PREFIX parameter to a null value.

In the initialization file for the database instance, set OS_AUTHENT_PREFIX as follows:
```
OS_AUTHENT_PREFIX=""
```

Note:

The default value for OS_AUTHENT_PREFIX is OPS$; however, you can set it to any string.
If a database already has the OS_AUTHENT_PREFIX set to a value other than NULL (" "), then do not change it, because it can inhibit previously created, externally identified users from connecting to the Oracle server.

After you have set OS_AUTHENT_PREFIX to null, then you can create external users by using the following syntax:

CREATE USER os_authent_prefix_username IDENTIFIED EXTERNALLY;

For example, to create the user king:

CREATE USER king IDENTIFIED EXTERNALLY;

The advantage of creating a user in this way is that you no longer need to maintain different user names for externally identified users. This is true for all supported authentication methods.

Parent topic: Configuring Oracle Database for External Authentication