Configuring Oracle Database Native Network Encryption and Data Integrity

16 Configuring Oracle Database Native Network Encryption and Data Integrity

You can configure native Oracle Net Services data encryption and data integrity for both servers and clients.

About Oracle Database Native Network Encryption and Data Integrity
Oracle Database enables you to encrypt data that is sent over a network.
Oracle Database Native Network Encryption Data Integrity
Encrypting network data provides data privacy so that unauthorized parties cannot view plaintext data as it passes over the network.
Data Integrity Algorithms Support
A keyed, sequenced implementation of the Message Digest 5 (MD5) algorithm or the Secure Hash Algorithm (SHA-1 and SHA-2) protect against these attacks.
Diffie-Hellman Based Key Negotiation
You can use the Diffie-Hellman key negotiation algorithm to secure data in a multiuser environment.
Configuration of Data Encryption and Integrity
Oracle Database native Oracle Net Services encryption and integrity presumes the prior installation of Oracle Net Services.

Parent topic: Securing Data on the Network

About Oracle Database Native Network Encryption and Data Integrity

Oracle Database enables you to encrypt data that is sent over a network.

How Oracle Database Native Network Encryption and Integrity Works
Oracle Database provides native data network encryption and integrity to ensure that data is secure as it travels across the network.
Advanced Encryption Standard
Oracle Database supports the Federal Information Processing Standard (FIPS) encryption algorithm, Advanced Encryption Standard (AES).
ARIA
Oracle Database supports the Academia, Research Institute, and Agency (ARIA) algorithm.
GOST
Oracle Database supports the GOsudarstvennyy STandart (GOST) algorithm.
SEED
Oracle Database supports the Korea Information Security Agency (KISA) encryption algorithm, SEED.
Triple-DES Support
Oracle Database supports Triple-DES encryption (3DES), which encrypts message data with three passes of the DES algorithm.

Parent topic: Configuring Oracle Database Native Network Encryption and Data Integrity

How Oracle Database Native Network Encryption and Integrity Works

Oracle Database provides native data network encryption and integrity to ensure that data is secure as it travels across the network.

The purpose of a secure cryptosystem is to convert plaintext data into unintelligible ciphertext based on a key, in such a way that it is very hard (computationally infeasible) to convert ciphertext back into its corresponding plaintext without knowledge of the correct key.

In a symmetric cryptosystem, the same key is used both for encryption and decryption of the same data. Oracle Database provides the Advanced Encryption Standard (AES) symmetric cryptosystem for protecting the confidentiality of Oracle Net Services traffic.

Parent topic: About Oracle Database Native Network Encryption and Data Integrity

Advanced Encryption Standard

Oracle Database supports the Federal Information Processing Standard (FIPS) encryption algorithm, Advanced Encryption Standard (AES).

AES can be used by all U.S. government organizations and businesses to protect sensitive data over a network. This encryption algorithm defines three standard key lengths, which are 128-bit, 192-bit, and 256-bit. All versions operate in outer Cipher Block Chaining (CBC) mode.

Parent topic: About Oracle Database Native Network Encryption and Data Integrity

ARIA

Oracle Database supports the Academia, Research Institute, and Agency (ARIA) algorithm.

This algorithm acknowledges the cooperative efforts of Korean researchers in designing the algorithm.

ARIA defines three standard key lengths, which are 128-bit, 192-bit, and 256-bit. All versions operate in outer cipher Cipher Block Chaining (CBC) mode.

Parent topic: About Oracle Database Native Network Encryption and Data Integrity

GOST

Oracle Database supports the GOsudarstvennyy STandart (GOST) algorithm.

The GOST algorithm was created by the Euro-Asian Council for Standardization, Metrology and Certification (EACS).

GOST defines a key size of 256-bits. In Oracle Database, outer Cipher Block Chaining (CBC) mode is used.

Parent topic: About Oracle Database Native Network Encryption and Data Integrity

SEED

Oracle Database supports the Korea Information Security Agency (KISA) encryption algorithm, SEED.

SEED defines a key size of 128-bits. There are extensions to the standard that defines additional key sizes of 192- and 256-bits, but Oracle Database does not support these extensions. In the Oracle Database, SEED operates in outer Cipher Block Chaining (CBC) mode.

Parent topic: About Oracle Database Native Network Encryption and Data Integrity

Triple-DES Support

Oracle Database supports Triple-DES encryption (3DES), which encrypts message data with three passes of the DES algorithm.

3DES provides a high degree of message security, but with a performance penalty. The magnitude of the performance penalty depends on the speed of the processor performing the encryption. 3DES typically takes three times as long to encrypt a data block when compared to the standard DES algorithm.

3DES is available in two-key and three-key versions, with effective key lengths of 112-bits and 168-bits, respectively. Both versions operate in outer Cipher Block Chaining (CBC) mode.

The DES40 algorithm, available with Oracle Database and Secure Network Services, is a variant of DES in which the secret key is preprocessed to provide 40 effective key bits. It was designed to provide DES-based encryption to customers outside the U.S. and Canada at a time when the U.S. export laws were more restrictive. Currently DES40, DES, and 3DES are all available for export. DES40 is still supported to provide backward-compatibility for international customers.

Parent topic: About Oracle Database Native Network Encryption and Data Integrity

Oracle Database Native Network Encryption Data Integrity

Encrypting network data provides data privacy so that unauthorized parties cannot view plaintext data as it passes over the network.

Oracle Database also provides protection against two forms of active attacks.

Table 16-1 provides information about these attacks.

Table 16-1 Two Forms of Network Attacks

Type of Attack	Explanation
Data modification attack	An unauthorized party intercepting data in transit, altering it, and retransmitting it is a data modification attack. For example, intercepting a $100 bank deposit, changing the amount to $10,000, and retransmitting the higher amount is a data modification attack.
Replay attack	Repetitively retransmitting an entire set of valid data is a replay attack, such as intercepting a $100 bank withdrawal and retransmitting it ten times, thereby receiving $1,000.

Parent topic: Configuring Oracle Database Native Network Encryption and Data Integrity

Data Integrity Algorithms Support

A keyed, sequenced implementation of the Message Digest 5 (MD5) algorithm or the Secure Hash Algorithm (SHA-1 and SHA-2) protect against these attacks.

Both of these hash algorithms create a checksum that changes if the data is altered in any way. This protection operates independently from the encryption process so you can enable data integrity with or without enabling encryption.

Related Topics

Configuring Integrity on the Client and the Server

Parent topic: Configuring Oracle Database Native Network Encryption and Data Integrity

Diffie-Hellman Based Key Negotiation

You can use the Diffie-Hellman key negotiation algorithm to secure data in a multiuser environment.

Secure key distribution is difficult in a multiuser environment. Oracle Database uses the well known Diffie-Hellman key negotiation algorithm to perform secure key distribution for both encryption and data integrity.

When encryption is used to protect the security of encrypted data, keys must be changed frequently to minimize the effects of a compromised key. Accordingly, the Oracle Database key management function changes the session key with every session.

You can use Authentication Key Fold-in to defeat a possible third-party attack (historically called the man-in-the-middle attack) on the Diffie-Hellman key negotiation algorithm key negotiation. It strengthens the session key significantly by combining a shared secret, known only to the client and the server, with the original session key negotiated by Diffie-Hellman.

The client and the server begin communicating using the session key generated by Diffie-Hellman. When the client authenticates to the server, they establish a shared secret that is only known to both parties. Oracle Database combines the shared secret and the Diffie-Hellman session key to generate a stronger session key designed to defeat a man-in-the-middle attack.

Note:

The authentication key fold-in function is an imbedded feature of Oracle Database and requires no configuration by the system or network administrator.

Parent topic: Configuring Oracle Database Native Network Encryption and Data Integrity

Configuration of Data Encryption and Integrity

Oracle Database native Oracle Net Services encryption and integrity presumes the prior installation of Oracle Net Services.

About Activating Encryption and Integrity
In any network connection, both the client and server can support multiple encryption algorithms and integrity algorithms.
About Negotiating Encryption and Integrity
The sqlnet.ora file on systems using data encryption and integrity must contain some or all the REJECTED, ACCEPTED, REQUESTED, and REQUIRED parameters.
Configuring Encryption and Integrity Parameters Using Oracle Net Manager
You can set up or change encryption and integrity parameter settings using Oracle Net Manager.

Parent topic: Configuring Oracle Database Native Network Encryption and Data Integrity

About Activating Encryption and Integrity

In any network connection, both the client and server can support multiple encryption algorithms and integrity algorithms.

When a connection is made, the server selects which algorithm to use, if any, from those algorithms specified in the sqlnet.ora files.The server searches for a match between the algorithms available on both the client and the server, and picks the first algorithm in its own list that also appears in the client list. If one side of the connection does not specify an algorithm list, all the algorithms installed on that side are acceptable. The connection fails with error message ORA-12650 if either side specifies an algorithm that is not installed.

Encryption and integrity parameters are defined by modifying a sqlnet.ora file on the clients and the servers on the network.

You can choose to configure any or all of the available encryption algorithms, and either or both of the available integrity algorithms. Only one encryption algorithm and one integrity algorithm are used for each connect session.

Note:

Oracle Database selects the first encryption algorithm and the first integrity algorithm enabled on the client and the server. Oracle recommends that you select algorithms and key lengths in the order in which you prefer negotiation, choosing the strongest key length first.

About Negotiating Encryption and Integrity

The sqlnet.ora file on systems using data encryption and integrity must contain some or all the REJECTED, ACCEPTED, REQUESTED, and REQUIRED parameters.

About the Values for Negotiating Encryption and Integrity
Oracle Net Manager can be used to specify four possible values for the encryption and integrity configuration parameters.
REJECTED Configuration Parameter
The REJECTED value disables the security service, even if the other side requires this service.
ACCEPTED Configuration Parameter
The ACCEPTED value enables the security service if the other side requires or requests the service.
REQUESTED Configuration Parameter
The REQUESTED value enables the security service if the other side permits this service.
REQUIRED Configuration Parameter
The REQUIRED value enables the security service or preclude the connection.

Parent topic: Configuration of Data Encryption and Integrity

About the Values for Negotiating Encryption and Integrity

Oracle Net Manager can be used to specify four possible values for the encryption and integrity configuration parameters.

The following four values are listed in the order of increasing security, and they must be used in the profile file (sqlnet.ora) for the client and server of the systems that are using encryption and integrity.

The value REJECTED provides the minimum amount of security between client and server communications, and the value REQUIRED provides the maximum amount of network security:

REJECTED
ACCEPTED
REQUESTED
REQUIRED

The default value for each of the parameters is ACCEPTED.

Oracle Database servers and clients are set to ACCEPT encrypted connections out of the box. This means that you can enable the desired encryption and integrity settings for a connection pair by configuring just one side of the connection, server-side or client-side.

So, for example, if there are many Oracle clients connecting to an Oracle database, you can configure the required encryption and integrity settings for all these connections by making the appropriate sqlnet.ora changes at the server end. You do not need to implement configuration changes for each client separately.

Table 16-2 shows whether the security service is enabled, based on a combination of client and server configuration parameters. If either the server or client has specified REQUIRED, the lack of a common algorithm causes the connection to fail. Otherwise, if the service is enabled, lack of a common service algorithm results in the service being disabled.

Table 16-2 Encryption and Data Integrity Negotiations

Client Setting	Server Setting	Encryption and Data Negotiation
`REJECTED`	`REJECTED`	`OFF`
`ACCEPTED`	`REJECTED`	`OFF`
`REQUESTED`	`REJECTED`	`OFF`
`REQUIRED`	`REJECTED`	Connection fails
`REJECTED`	`ACCEPTED`	`OFF`
`ACCEPTED`	`ACCEPTED`	`OFF`^Foot 1
`REQUESTED`	`ACCEPTED`	`ON`
`REQUIRED`	`ACCEPTED`	`ON`
`REJECTED`	`REQUESTED`	`OFF`
`ACCEPTED`	`REQUESTED`	`ON`
`REQUESTED`	`REQUESTED`	`ON`
`REQUIRED`	`REQUESTED`	`ON`
`REJECTED`	`REQUIRED`	Connection fails
`ACCEPTED`	`REQUIRED`	`ON`
`REQUESTED`	`REQUIRED`	`ON`
`REQUIRED`	`REQUIRED`	`ON`

^Footnote 1

This value defaults to OFF. Cryptography and data integrity are not enabled until the user changes this parameter by using Oracle Net Manager or by modifying the sqlnet.ora file.

Parent topic: About Negotiating Encryption and Integrity

REJECTED Configuration Parameter

The REJECTED value disables the security service, even if the other side requires this service.

In this scenario, this side of the connection specifies that the security service is not permitted. If the other side is set to REQUIRED, the connection terminates with error message ORA-12650. If the other side is set to REQUESTED, ACCEPTED, or REJECTED, the connection continues without error and without the security service enabled.

Parent topic: About Negotiating Encryption and Integrity

ACCEPTED Configuration Parameter

The ACCEPTED value enables the security service if the other side requires or requests the service.

In this scenario, this side of the connection does not require the security service, but it is enabled if the other side is set to REQUIRED or REQUESTED. If the other side is set to REQUIRED or REQUESTED, and an encryption or integrity algorithm match is found, the connection continues without error and with the security service enabled. If the other side is set to REQUIRED and no algorithm match is found, the connection terminates with error message ORA-12650.

If the other side is set to REQUESTED and no algorithm match is found, or if the other side is set to ACCEPTED or REJECTED, the connection continues without error and without the security service enabled.

Parent topic: About Negotiating Encryption and Integrity

REQUESTED Configuration Parameter

The REQUESTED value enables the security service if the other side permits this service.

In this scenario, this side of the connection specifies that the security service is desired but not required. The security service is enabled if the other side specifies ACCEPTED, REQUESTED, or REQUIRED. There must be a matching algorithm available on the other side, otherwise the service is not enabled. If the other side specifies REQUIRED and there is no matching algorithm, the connection fails.

Parent topic: About Negotiating Encryption and Integrity

REQUIRED Configuration Parameter

The REQUIRED value enables the security service or preclude the connection.

In this scenario, this side of the connection specifies that the security service must be enabled. The connection fails if the other side specifies REJECTED or if there is no compatible algorithm on the other side.

Parent topic: About Negotiating Encryption and Integrity

Configuring Encryption and Integrity Parameters Using Oracle Net Manager

You can set up or change encryption and integrity parameter settings using Oracle Net Manager.

Configuring Encryption on the Client and the Server
Use Oracle Net Manager to configure encryption on the client and on the server.
Configuring Integrity on the Client and the Server
You can use Oracle Net Manager to configure network integrity on both the client and the server.
Enabling Both Oracle Native Encryption and SSL Authentication for Different Users Concurrently
Depending on the SQLNET.ENCRYPTION_CLIENT and SQLNET.ENCRYPTION_SERVER settings, you can configure Oracle Database to allow both Oracle native encryption and SSL authentication for different users concurrently.

Parent topic: Configuration of Data Encryption and Integrity

Configuring Encryption on the Client and the Server

Use Oracle Net Manager to configure encryption on the client and on the server.

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 Encryption tab.

Description of the illustration asoencry_12102.png
Select CLIENT or SERVER option from the Encryption box.
From the Encryption Type list, select one of the following:
- REQUESTED
- REQUIRED
- ACCEPTED
- REJECTED
(Optional) In the Encryption Seed field, enter between 10 and 70 random characters. The encryption seed for the client should not be the same as that for the server.
Select an encryption algorithm in the Available Methods list. Move it to the Selected Methods list by choosing the right arrow (>). Repeat for each additional method you want to use.
Select File, Save Network Configuration. The sqlnet.ora file is updated.

Repeat this procedure to configure encryption on the other system. The sqlnet.ora file on the two systems should contain the following entries:

On the server:

SQLNET.ENCRYPTION_SERVER = [accepted | rejected | requested | required]
SQLNET.ENCRYPTION_TYPES_SERVER = (valid_encryption_algorithm [,valid_encryption_algorithm])

On the client:

SQLNET.ENCRYPTION_CLIENT = [accepted | rejected | requested | required]
SQLNET.ENCRYPTION_TYPES_CLIENT = (valid_encryption_algorithm [,valid_encryption_algorithm])

Table 16-3 lists valid encryption algorithms and their associated legal values.

Table 16-3 Valid Encryption Algorithms

Algorithm Name	Legal Value
AES 256-bit key	AES256
AES 192-bit key	AES192
AES 128-bit key	AES128

Parent topic: Configuring Encryption and Integrity Parameters Using Oracle Net Manager

Configuring Integrity on the Client and the Server

You can use Oracle Net Manager to configure network integrity on both the client and the server.

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 Integrity tab.

Description of the illustration cfig0002.gif
Depending upon which system you are configuring, select the Server or Client from the Integrity box.
From the Checksum Level list, select one of the following checksum level values:
- REQUESTED
- REQUIRED
- ACCEPTED
- REJECTED
Select an integrity algorithm in the Available Methods list. Move it to the Selected Methods list by choosing the right arrow (>). Repeat for each additional method you want to use.
Select File, Save Network Configuration.

The sqlnet.ora file is updated.

Repeat this procedure to configure integrity on the other system.

The sqlnet.ora file on the two systems should contain the following entries:

On the server:

SQLNET.CRYPTO_CHECKSUM_SERVER = [accepted | rejected | requested | required]
SQLNET.CRYPTO_CHECKSUM_TYPES_SERVER = (valid_crypto_checksum_algorithm [,valid_crypto_checksum_algorithm])

On the client:

SQLNET.CRYPTO_CHECKSUM_CLIENT = [accepted | rejected | requested | required]
SQLNET.CRYPTO_CHECKSUM_TYPES_CLIENT = (valid_crypto_checksum_algorithm [,valid_crypto_checksum_algorithm])

Enabling Both Oracle Native Encryption and SSL Authentication for Different Users Concurrently

Depending on the SQLNET.ENCRYPTION_CLIENT and SQLNET.ENCRYPTION_SERVER settings, you can configure Oracle Database to allow both Oracle native encryption and SSL authentication for different users concurrently.

About Enabling Both Oracle Native Encryption and SSL Authentication for Different Users Concurrently
By default, Oracle Database does not allow both Oracle native encryption and Secure Sockets Layer (SSL) authentication for different users concurrently.
Configuring Both Oracle Native Encryption and SSL Authentication for Different Users Concurrently
Use the IGNORE_ANO_ENCRYPTION_FOR_TCPS parameter to enable the concurrent use of both Oracle native encryption and Secure Sockets Layer (SSL) authentication.

Parent topic: Configuring Encryption and Integrity Parameters Using Oracle Net Manager

About Enabling Both Oracle Native Encryption and SSL Authentication for Different Users Concurrently

By default, Oracle Database does not allow both Oracle native encryption and Secure Sockets Layer (SSL) authentication for different users concurrently.

The use of both Oracle native encryption (also called Advanced Networking Option (ANO) encryption) and SSL authentication together is called double encryption. Suppose the client has the SQLNET.ENCRYPTION_CLIENT parameter set to required and the server has the SQLNET.ENCRYPTION_SERVER parameter set to required. If a TCPS listener is used, then the connection is refused and the ORA-12696: Double Encryption Turned On, login disallowed error is returned.

However, there are cases in which both a TCP and TCPS listener must be configured, so that some users can connect to the server using a user name and password, and others can validate to the server by using an SSL certificate. In these situations, you must configure both password-based authentication and SSL authentication. A workaround in previous releases was to set the SQLNET.ENCRYPTION_SERVER parameter to requested. If your requirements are that SQLNET.ENCRYPTION_SERVER be set to required, then you can set the IGNORE_ANO_ENCRYPTION_FOR_TCPS parameter in both SQLNET.ENCRYPTION_CLIENT and SQLNET.ENCRYPTION_SERVER to TRUE. By default, it is set to FALSE.

Setting IGNORE_ANO_ENCRYPTION_FOR_TCPS to TRUE forces the client to ignore the value that is set for the SQLNET.ENCRYPTION_CLIENT parameter for all outgoing TCPS connections. Instead of returning the ORA-12696 error when both TCPS and ANO are configured, this parameter allows the database to ignore the SQLNET.ENCRYPTION_CLIENT or SQLNET.ENCRYPTION_SERVER setting when there is a conflict between the use of a TCPS client and when these two parameters are set to required.

Parent topic: Enabling Both Oracle Native Encryption and SSL Authentication for Different Users Concurrently

Configuring Both Oracle Native Encryption and SSL Authentication for Different Users Concurrently

Use the IGNORE_ANO_ENCRYPTION_FOR_TCPS parameter to enable the concurrent use of both Oracle native encryption and Secure Sockets Layer (SSL) authentication.

On the server, you must set IGNORE_ANO_ENCRYPTION_FOR_TCPS in the sqlnet.ora file, and on the client, you can set it in either the sqlnet.ora file or the tnsnames.ora file.

Log in to the database server
Go to the location of the sqlnet.ora file.
By default, sqlnet.ora is in the ORACLE_BASE/network/admin directory. The sqlnet.ora file can also be stored in the directory specified by the TNS_ADMIN environment variable.
In sqlnet.ora, check if the current SQLNET.ENCRYPTION_SERVER setting is required or requested.
If SQLNET.ENCRYPTION_SERVER is set to required, then add the SQLNET.IGNORE_ANO_ENCRYPTION_FOR_TCPS to sqlnet.ora and then set it to TRUE.
```
IGNORE_ANO_ENCRYPTION_FOR_TCPS=TRUE
```
Save and exit sqlnet.ora.
Log in to the client.
For the client, you can set the value in either the sqlnet.ora file or the tnsnames.ora file.
- Setting the value in sqlnet.ora: Check if the SQLNET.ENCRYPTION_CLIENT parameter is set to required. If SQLNET.ENCRYPTION_CLIENT, then edit the sqlnet.ora file to have the following setting:
```
IGNORE_ANO_ENCRYPTION_FOR_TCPS=TRUE
```
- Setting the value in tnsnames.ora: By default, tnsnames.ora is in the same location as sqlnet.ora. If SQLNET.ENCRYPTION_CLIENT is set to required in sqlnet.ora, then in the SECURITY portion of the TNS_ALIAS setting, set IGNORE_ANO_ENCRYPTION_FOR_TCPS=TRUE. For example:
```
test_ssl=
    (DESCRIPTION =
       (ADDRESS=(PROTOCOL=tcps)(HOST=)(PORT=1750))
       (CONNECT_DATA=(SID=^ORACLE_SID^))
       (SECURITY=(IGNORE_ANO_ENCRYPTION_FOR_TCPS=TRUE))
     ) 
```

Parent topic: Enabling Both Oracle Native Encryption and SSL Authentication for Different Users Concurrently