Oracle native network encryption

Amazon RDS supports Oracle native network encryption (NNE). With native network encryption, you can encrypt data as it moves to and from a DB instance. Amazon RDS supports NNE for all editions of Oracle Database.

A detailed discussion of Oracle native network encryption is beyond the scope of this guide, but you should understand the strengths and weaknesses of each algorithm and key before you decide on a solution for your deployment. For information about the algorithms and keys that are available through Oracle native network encryption, see Configuring network data encryption in the Oracle documentation. For more information about AWS security, see the AWS security center.

Note

You can use Native Network Encryption or Secure Sockets Layer, but not both. For more information, see Oracle Secure Sockets Layer.

NNE option settings

You can specify encryption requirements on both the server and the client. The DB instance can act as a client when, for example, it uses a database link to connect to another database. You might want to avoid forcing encryption on the server side. For example, you might not want to force all client communications to use encryption because the server requires it. In this case, you can force encryption on the client side using the SQLNET.*CLIENT options.

Amazon RDS supports the following settings for the NNE option.

Note

When you use commas to separate values for an option setting, don't put a space after the comma.

Option setting	Valid values	Default values	Description
SQLNET.ALLOW_WEAK_CRYPTO_CLIENTS	TRUE, FALSE	TRUE	The behavior of the server when a client using a non-secure cipher attempts to connect to the database. If TRUE, clients can connect even if they aren't patched with the July 2021 PSU. If the setting is FALSE, clients can connect to the database only when they are patched with the July 2021 PSU. Before you set SQLNET.ALLOW_WEAK_CRYPTO_CLIENTS to FALSE, make sure that the following conditions are met: SQLNET.ENCRYPTION_TYPES_SERVER and SQLNET.ENCRYPTION_TYPES_CLIENT have one matching encryption method that is not DES, 3DES, or RC4 (all key lengths). SQLNET.CHECKSUM_TYPES_SERVER and SQLNET.CHECKSUM_TYPES_CLIENT have one matching secure checksumming method that is not MD5. The client is patched with the July 2021 PSU. If the client isn't patched, the client loses the connection and receives the ORA-12269 error.
SQLNET.ALLOW_WEAK_CRYPTO	TRUE, FALSE	TRUE	The behavior of the server when a client using a non-secure cipher attempts to connect to the database. The following ciphers are considered not secure: DES encryption method (all key lengths) 3DES encryption method (all key lengths) RC4 encryption method (all key lengths) MD5 checksumming method If the setting is TRUE, clients can connect when they use the preceding non-secure ciphers. If the setting is FALSE, the database prevents clients from connecting when they use the preceding non-secure ciphers. Before you set SQLNET.ALLOW_WEAK_CRYPTO to FALSE, make sure that the following conditions are met: SQLNET.ENCRYPTION_TYPES_SERVER and SQLNET.ENCRYPTION_TYPES_CLIENT have one matching encryption method that is not DES, 3DES, or RC4 (all key lengths). SQLNET.CHECKSUM_TYPES_SERVER and SQLNET.CHECKSUM_TYPES_CLIENT have one matching secure checksumming method that is not MD5. The client is patched with the July 2021 PSU. If the client isn't patched, the client loses the connection and receives the ORA-12269 error.
SQLNET.CRYPTO_CHECKSUM_CLIENT	Accepted, Rejected, Requested, Required	Requested	The data integrity behavior when a DB instance connects to the client, or a server acting as a client. When a DB instance uses a database link, it acts as a client. Requested indicates that the client doesn't require the DB instance to perform a checksum.
SQLNET.CRYPTO_CHECKSUM_SERVER	Accepted, Rejected, Requested, Required	Requested	The data integrity behavior when a client, or a server acting as a client, connects to the DB instance. When a DB instance uses a database link, it acts as a client. Requested indicates that the DB instance doesn't require the client to perform a checksum.
SQLNET.CRYPTO_CHECKSUM_TYPES_CLIENT	SHA256, SHA384, SHA512, SHA1, MD5	SHA256, SHA384, SHA512	A list of checksum algorithms. You can specify either one value or a comma-separated list of values. If you use a comma, don't insert a space after the comma; otherwise, you receive an InvalidParameterValue error. This parameter and SQLNET.CRYPTO_CHECKSUM_TYPES_SERVER must have a common cipher.
SQLNET.CRYPTO_CHECKSUM_TYPES_SERVER	SHA256, SHA384, SHA512, SHA1, MD5	SHA256, SHA384, SHA512, SHA1, MD5	A list of checksum algorithms. You can specify either one value or a comma-separated list of values. If you use a comma, don't insert a space after the comma; otherwise, you receive an InvalidParameterValue error. This parameter and SQLNET.CRYPTO_CHECKSUM_TYPES_CLIENT must have a common cipher.
SQLNET.ENCRYPTION_CLIENT	Accepted, Rejected, Requested, Required	Requested	The encryption behavior of the client when a client, or a server acting as a client, connects to the DB instance. When a DB instance uses a database link, it acts as a client. Requested indicates that the client does not require traffic from the server to be encrypted.
SQLNET.ENCRYPTION_SERVER	Accepted, Rejected, Requested, Required	Requested	The encryption behavior of the server when a client, or a server acting as a client, connects to the DB instance. When a DB instance uses a database link, it acts as a client. Requested indicates that the DB instance does not require traffic from the client to be encrypted.
SQLNET.ENCRYPTION_TYPES_CLIENT	RC4_256, AES256, AES192, 3DES168, RC4_128, AES128, 3DES112, RC4_56, DES, RC4_40, DES40	RC4_256, AES256, AES192, 3DES168, RC4_128, AES128, 3DES112, RC4_56, DES, RC4_40, DES40	A list of encryption algorithms used by the client. The client attempts to decrypt the server input by trying each algorithm in order, proceeding until an algorithm succeeds or the end of the list is reached. Amazon RDS uses the following default list from Oracle. RDS starts with RC4_256 and proceeds down the list in order. You can change the order or limit the algorithms that the DB instance will accept. RC4_256: RSA RC4 (256-bit key size) AES256: AES (256-bit key size) AES192: AES (192-bit key size) 3DES168: 3-key Triple-DES (112-bit effective key size) RC4_128: RSA RC4 (128-bit key size) AES128: AES (128-bit key size) 3DES112: 2-key Triple-DES (80-bit effective key size) RC4_56: RSA RC4 (56-bit key size) DES: Standard DES (56-bit key size) RC4_40: RSA RC4 (40-bit key size) DES40: DES40 (40-bit key size) You can specify either one value or a comma-separated list of values. If you a comma, don't insert a space after the comma; otherwise, you receive an InvalidParameterValue error. This parameter and SQLNET.SQLNET.ENCRYPTION_TYPES_SERVER must have a common cipher.
SQLNET.ENCRYPTION_TYPES_SERVER	RC4_256, AES256, AES192, 3DES168, RC4_128, AES128, 3DES112, RC4_56, DES, RC4_40, DES40	RC4_256, AES256, AES192, 3DES168, RC4_128, AES128, 3DES112, RC4_56, DES, RC4_40, DES40	A list of encryption algorithms used by the DB instance. The DB instance uses each algorithm, in order, to attempt to decrypt the client input until an algorithm succeeds or until the end of the list is reached. Amazon RDS uses the following default list from Oracle. You can change the order or limit the algorithms that the client will accept. RC4_256: RSA RC4 (256-bit key size) AES256: AES (256-bit key size) AES192: AES (192-bit key size) 3DES168: 3-key Triple-DES (112-bit effective key size) RC4_128: RSA RC4 (128-bit key size) AES128: AES (128-bit key size) 3DES112: 2-key Triple-DES (80-bit effective key size) RC4_56: RSA RC4 (56-bit key size) DES: Standard DES (56-bit key size) RC4_40: RSA RC4 (40-bit key size) DES40: DES40 (40-bit key size) You can specify either one value or a comma-separated list of values. If you a comma, don't insert a space after the comma; otherwise, you receive an InvalidParameterValue error. This parameter and SQLNET.SQLNET.ENCRYPTION_TYPES_SERVER must have a common cipher.

Adding the NNE option

The general process for adding the NNE option to a DB instance is the following:

1. Create a new option group, or copy or modify an existing option group.

2. Add the option to the option group.

3. Associate the option group with the DB instance.

When the option group is active, NNE is active.

To add the NNE option to a DB instance using the AWS Management Console

1. For Engine, choose the Oracle edition that you want to use. NNE is supported on all editions.

2. For Major engine version, choose the version of your DB instance.

   For more information, see Creating an option group.

3. Add the NNE option to the option group. For more information about adding options, see Adding an option to an option group.

   Note

   After you add the NNE option, you don't need to restart your DB instances. As soon as the option group is active, NNE is active.

4. Apply the option group to a new or existing DB instance:

   • For a new DB instance, you apply the option group when you launch the instance. For more information, see Creating an Amazon RDS DB instance.

   • For an existing DB instance, you apply the option group by modifying the instance and attaching the new option group. After you add the NNE option, you don't need to restart your DB instance. As soon as the option group is active, NNE is active. For more information, see Modifying an Amazon RDS DB instance.

Setting NNE values in the sqlnet.ora

With Oracle native network encryption, you can set network encryption on the server side and client side. The client is the computer used to connect to the DB instance. You can specify the following client settings in the sqlnet.ora:

• SQLNET.ALLOW_WEAK_CRYPTO

• SQLNET.ALLOW_WEAK_CRYPTO_CLIENTS

• SQLNET.CRYPTO_CHECKSUM_CLIENT

• SQLNET.CRYPTO_CHECKSUM_TYPES_CLIENT

• SQLNET.ENCRYPTION_CLIENT

• SQLNET.ENCRYPTION_TYPES_CLIENT

For information, see Configuring network data encryption and integrity for Oracle servers and clients in the Oracle documentation.

Sometimes, the DB instance rejects a connection request from an application. For example, a rejection can occur when the encryption algorithms on the client and on the server don't match. To test Oracle native network encryption, add the following lines to the sqlnet.ora file on the client:

DIAG_ADR_ENABLED=off
TRACE_DIRECTORY_CLIENT=/tmp
TRACE_FILE_CLIENT=nettrace
TRACE_LEVEL_CLIENT=16

When a connection is attempted, the preceding lines generate a trace file on the client called /tmp/nettrace*. The trace file contains information about the connection. For more information about connection-related issues when you are using Oracle Native Network Encryption, see About negotiating encryption and integrity in the Oracle Database documentation.

Modifying NNE option settings

After you enable NNE, you can modify its settings. Currently, you can modify NNE option settings only with the AWS CLI or RDS API. You can't use the console. To learn how to modify option settings using the CLI, see AWS CLI. For more information about each setting, see NNE option settings.

Modifying CRYPTO_CHECKSUM_* values

If you modify NNE option settings, make sure that the following option settings have at least one common cipher:

• SQLNET.CRYPTO_CHECKSUM_TYPES_SERVER

• SQLNET.CRYPTO_CHECKSUM_TYPES_CLIENT

The following example shows a scenario in which you modify SQLNET.CRYPTO_CHECKSUM_TYPES_SERVER. The configuration is valid because the CRYPTO_CHECKSUM_TYPES_CLIENT and CRYPTO_CHECKSUM_TYPES_SERVER both use SHA256.

Option setting	Values before modification	Values after modification
SQLNET.CRYPTO_CHECKSUM_TYPES_CLIENT	SHA256, SHA384, SHA512	No change
SQLNET.CRYPTO_CHECKSUM_TYPES_SERVER	SHA256, SHA384, SHA512, SHA1, MD5	SHA1,MD5,SHA256

For another example, assume that you want to modify SQLNET.CRYPTO_CHECKSUM_TYPES_SERVER from its default setting to SHA1,MD5. In this case, make sure you set SQLNET.CRYPTO_CHECKSUM_TYPES_CLIENT to SHA1 or MD5. These algorithms aren't included in the default values for SQLNET.CRYPTO_CHECKSUM_TYPES_CLIENT.

Modifying ALLOW_WEAK_CRYPTO* settings

To set the SQLNET.ALLOW_WEAK_CRYPTO* options from the default value to FALSE, make sure that the following conditions are met:

• SQLNET.ENCRYPTION_TYPES_SERVER and SQLNET.ENCRYPTION_TYPES_CLIENT have one matching secure encryption method. A method is considered secure if it's not DES, 3DES, or RC4 (all key lengths).

• SQLNET.CHECKSUM_TYPES_SERVER and SQLNET.CHECKSUM_TYPES_CLIENT have one matching secure checksumming method. A method is considered secure if it's not MD5.

• The client is patched with the July 2021 PSU. If the client isn't patched, the client loses the connection and receives the ORA-12269 error.

The following example shows sample NNE settings. Assume that you want to set SQLNET.ENCRYPTION_TYPES_SERVER and SQLNET.ENCRYPTION_TYPES_CLIENT to FALSE, thereby blocking non-secure connections. The checksum option settings meet the prerequisites because they both have SHA256. However, SQLNET.ENCRYPTION_TYPES_CLIENT and SQLNET.ENCRYPTION_TYPES_SERVER use the DES, 3DES, and RC4 encryption methods, which are non-secure. Therefore, to set the SQLNET.ALLOW_WEAK_CRYPTO* options to FALSE, first set SQLNET.ENCRYPTION_TYPES_SERVER and SQLNET.ENCRYPTION_TYPES_CLIENT to a secure encryption method such as AES256.

Option setting	Values
SQLNET.CRYPTO_CHECKSUM_TYPES_CLIENT	SHA256, SHA384, SHA512
SQLNET.CRYPTO_CHECKSUM_TYPES_SERVER	SHA1,MD5,SHA256
SQLNET.ENCRYPTION_TYPES_CLIENT	RC4_256, 3DES168, DES40
SQLNET.ENCRYPTION_TYPES_SERVER	RC4_256, 3DES168, DES40

Removing the NNE option

You can remove NNE from a DB instance.

To remove NNE from a DB instance, do one of the following:

• To remove NNE from multiple DB instances, remove the NNE option from the option group they belong to. This change affects all DB instances that use the option group. After you remove the NNE option, you don't need to restart your DB instances. For more information, see Removing an option from an option group.

• To remove NNE from a single DB instance, modify the DB instance and specify a different option group that doesn't include the NNE option. You can specify the default (empty) option group, or a different custom option group. After you remove the NNE option, you don't need to restart your DB instance. For more information, see Modifying an Amazon RDS DB instance.