Security in Kafka Stages

You can configure the Kafka Multitopic Consumer origin and the Kafka Producer destination to use one of the following security options to connect securely to Kafka:

The SASL authentication options provide two SASL mechanisms: PLAIN or GSSAPI (Kerberos).

Enabling security requires completing several prerequisite tasks in addition to configuring security properties in the stage.

Prerequisite Tasks

Before enabling security for a Kafka stage, complete the prerequisite tasks for the security method that you want to use:

SSL/TLS

Complete the following prerequisite task before using SSL/TLS to connect to Kafka:

Before using SSL/TLS to connect to Kafka, make sure Kafka is configured for SSL/TLS as described in the Kafka documentation.

SASL with the PLAIN mechanism

Complete the following prerequisite tasks before using SASL with the PLAIN mechanism to connect to Kafka:

Make sure Kafka is configured for SASL authentication with the PLAIN mechanism as described in the Kafka documentation.
Define the user name and password credentials in a JAAS configuration file, as described in Providing PLAIN Credentials.

SASL with the GSSAPI (Kerberos) mechanism

Complete the following prerequisite tasks before using SASL with the GSSAPI (Kerberos) mechanism to connect to Kafka:

Make sure Kafka is configured for SASL authentication with the GSSAPI (Kerberos) mechanism as described in the Kafka documentation.
Make sure that Kerberos authentication is enabled for Data Collector, as described in Kerberos Authentication.
Determine how to provide the Kerberos credentials and complete the required tasks as described in Providing Kerberos Credentials.

SASL Authentication Credentials

When using SASL authentication to connect to Kafka, the method that you use to provide credentials depends on whether you use the PLAIN or GSSAPI (Kerberos) SASL mechanism.

Providing PLAIN Credentials

To connect to Kafka using SASL authentication with the PLAIN mechanism, provide the credentials in a Java Authentication and Authorization Service (JAAS) file.

Create a JAAS configuration file on the Data Collector machine. You can define a single JAAS file for Data Collector. As a result, every Kafka connection in every pipeline that uses SASL authentication with the PLAIN mechanism uses the same credentials.

Add the following KafkaClient login section to the file:

KafkaClient {
    org.apache.kafka.common.security.plain.PlainLoginModule required 
    username="<username>" 
    password="<password>";
};

Then modify the Java configuration options used by the deployment to include the option that defines the path to the JAAS configuration file. In Control Hub, edit the deployment. In the Configure Engine section, click Advanced Configuration. Then, click Java Configuration. Add the following option to the Java Options property:

-Djava.security.auth.login.config=<JAAS config path>/kafka_client_jaas.conf

Providing Kerberos Credentials

To connect to Kafka using SASL authentication with the GSSAPI (Kerberos) mechanism, you must provide the Kerberos credentials to use.

You can provide Kerberos credentials in either of the following ways. You can also use both methods, as needed:

JAAS file

Define Kerberos credentials in a Java Authentication and Authorization Service (JAAS) file when you want to use the same keytab and principal for every Kafka connection in every pipeline that you create. When configured, credentials defined in connection properties override JAAS file credentials.

You might use this method to provide a default keytab and principal. Then, use connection properties to specify different credentials, as needed.

To use a JAAS file, create a separate JAAS configuration file on the Data Collector machine. Add the following KafkaClient login section to the file:

KafkaClient {
    com.sun.security.auth.module.Krb5LoginModule required
    useKeyTab=true
    keyTab="<keytab path>"
    principal="<principal name>/<host name>@<realm>";
};

-Djava.security.auth.login.config=<JAAS config path>/kafka_client_jaas.conf

Stage properties

You can define Kerberos credentials in stage properties when the Kafka stage uses a stage library for Kafka 0.11.0.0 or higher. Define Kerberos credentials in stage properties when you want to use different credentials in different Kafka stages.

If you also configure a JAAS file to provide Kerberos credentials, the credentials that you enter in stage properties overrides those in the JAAS file.

To provide Kerberos credentials in stage properties, you select the Provide Keytab property on the Security tab of the stage. You specify the principal in plain text, then you use one of the following methods to specify the keytab:

Enter a Base64-encoded keytab in the Runtime Keytab property.
Encode the keytab before entering it in the stage property. Be sure to remove unnecessary characters, such as newline characters, before encoding the keytab.
Use a credential function to access a Base64-encoded keytab defined in a credential store.
For more information, see Using a Credential Store.

For details on enabling Kafka connections to use SASL authentication with the GSSAPI (Kerberos) mechanism, see Enabling SASL Authentication or Enabling SASL Authentication on SSL/TLS.

Using a Credential Store

You can define Kerberos keytabs in a credential store, then call the appropriate keytab from a Kafka stage.

Defining Kerberos keytabs in a credential store allows you to store multiple keytabs for use by Kafka stages. It also provides flexibility in how you use the keytabs. For example, you might create two separate keytabs, one for Kafka origins and one for Kafka destinations. Or, you might provide separate keytabs for every Kafka stage that you define.

Using a credential store makes it easy to update keytabs without having to edit the stages that use them. This can simplify tasks such as recycling keytabs or migrating pipelines to production.

Make sure that Data Collector is configured to use a supported credential store. For a list of supported credential stores and instructions on enabling each credential store, see Credential Stores.

For an additional layer of security, you can require group access to credential store secrets.

Enabling SSL/TLS Encryption

When the Kafka cluster uses the Kafka SSL security protocol, enable the Kafka stage to use SSL/TLS encryption.

Before you enable Kafka stages to use SSL/TLS, make sure that you have performed all necessary prerequisite tasks. Then, perform the following steps to enable the Kafka stages to use SSL/TLS to connect to Kafka.

On the General tab of the stage, set the Stage Library property to the appropriate Kafka version.
On the Kafka tab of the stage, configure each Kafka broker URI to use the SSL/TLS port.

The default SSL/TLS port number is 9093.

On the Security tab, configure the following properties:


Security Property	Description
Security Option	Set to SSL/TLS Encryption (Security Protocol=SSL).
Truststore Type	Type of truststore to use. Use one of the following types: Java Keystore File (JKS) PKCS #12 (p12 file) Default is Java Keystore File (JKS).
Truststore File	Path to the truststore file. Enter an absolute path to the file or enter the following expression to define the file stored in the Data Collector resources directory: `${runtime:resourcesDirPath()}/keystore.jks`
Truststore Password	Password to the truststore file. Tip: To secure sensitive information such as passwords, you can use runtime resources or credential stores.
Enabled Protocols	Comma-separated list of protocols used to connect to the Kafka brokers. Ensure that at least one of these protocols is enabled in the Kafka brokers. Note: Older protocols are not as secure as TLSv1.2.

Enabling SSL/TLS Encryption and Authentication

When the Kafka cluster uses the Kafka SSL security protocol and requires client authentication, enable the Kafka stage to use SSL/TLS encryption and authentication.

Before you enable a Kafka stage to use SSL/TLS encryption and authentication, make sure that you have performed all necessary prerequisite tasks. Then, perform the following steps to enable the stage to use SSL/TLS encryption and authentication to connect to Kafka.

On the General tab of the stage, set the Stage Library property to the appropriate Kafka version.
On the Kafka tab of the stage, configure each Kafka broker URI to use the SSL/TLS port.

The default SSL/TLS port number is 9093.

On the Security tab, configure the following properties:


Security Property	Description
Security Option	Set to SSL/TLS Encryption and Authentication (Security Protocol=SSL).
Truststore Type	Type of truststore to use. Use one of the following types: Java Keystore File (JKS) PKCS #12 (p12 file) Default is Java Keystore File (JKS).
Truststore File	Path to the truststore file. Enter an absolute path to the file or enter the following expression to define the file stored in the Data Collector resources directory: `${runtime:resourcesDirPath()}/keystore.jks`
Truststore Password	Password to the truststore file. Tip: To secure sensitive information such as passwords, you can use runtime resources or credential stores.
Keystore Type	Type of keystore to use. Use one of the following types: Java Keystore File (JKS) PKCS #12 (p12 file) Default is Java Keystore File (JKS).
Keystore File	Path to the keystore file. Enter an absolute path to the file or enter the following expression to define the file stored in the Data Collector resources directory: `${runtime:resourcesDirPath()}/keystore.jks`
Keystore Password	Password to the keystore file.
Key Password	Password for the key in the keystore file. Tip: To secure sensitive information such as passwords, you can use runtime resources or credential stores.
Enabled Protocols	Comma-separated list of protocols used to connect to the Kafka brokers. Ensure that at least one of these protocols is enabled in the Kafka brokers. Note: Older protocols are not as secure as TLSv1.2.

Enabling SASL Authentication

When the Kafka cluster uses the Kafka SASL_PLAINTEXT security protocol, enable the Kafka stage to use SASL authentication.

Before you enable Kafka stages to use SASL authentication, make sure that you have performed all necessary prerequisite tasks.

Note: The following steps provide details on providing Kerberos credentials using a JAAS file or stage properties. You can use either method or both. Skip the steps that are not relevant to your desired implementation.

To use a Java Authentication and Authorization Service (JAAS) file to provide plain or Kerberos credentials, create a JAAS configuration file on the Data Collector machine.

The contents of the JAAS configuration file depend on whether you use the PLAIN or GSSAPI (Kerberos) SASL mechanism and depend on your Data Collector installation and authentication type. For details, see Providing PLAIN Credentials or Providing Kerberos Credentials.
If using the GSSAPI (Kerberos) SASL mechanism and a credential store to call keytabs from stage properties, add the Base64-encoded keytabs that you want to use to the credential store.

Note: Be sure to remove unnecessary characters, such as newline characters, before encoding the keytab.

If you configured Data Collector to require group secrets, for each keytab secret that you define, create a group secret and specify a comma-separated list of groups allowed to access the keytab secret.

Name the group secret based on the keytab secret name, as follows: <keytab secret name>-groups.

For details on defining secrets, see your credential store documentation.
On the General tab of the Kafka stage, set the Stage Library property to the appropriate Kafka version.

If using stage properties to define Kafka credentials, select a stage library for Kafka version 0.11.0.0 or later.

On the Security tab of the stage, configure the following properties:


Security Property	Description
Security Option	Set to SASL Authentication (Security Protocol=SASL_PLAINTEXT).
SASL Mechanism	SASL mechanism to use: PLAIN GSSAPI (Kerberos)
Kerberos Service Name	Kerberos service principal name that the Kafka brokers run as. Available when using the GSSAPI (Kerberos) mechanism.
Provide Keytab at Runtime	Enables providing Kerberos credentials in the connection properties. Important: Configuring Kerberos credentials in connection properties is not supported in Transformer pipelines at this time. Available when using the GSSAPI (Kerberos) mechanism.
Runtime Keytab	Kerberos keytab to use for the connection, specified in one of the following ways: Enter a Base64-encoded keytab. Be sure to remove unnecessary characters, such as newline characters, before encoding the keytab. If using a credential store, use the `credential:get()` or `credential:getWithOptions()` credential function to retrieve a Base64-encoded keytab. Note: The user who starts the pipeline must be in the Data Collector group specified in the credential function. When Data Collector requires a group secret, the user must also be in a group associated with the keytab. For more information about using keytabs in a credential store, see Using a Credential Store. Available when using the GSSAPI (Kerberos) mechanism.
Runtime Principal	Kerberos principal to use for the connection, specified in the following format: `<principal name>/<host name>@<realm>`. Available when using the GSSAPI (Kerberos) mechanism.

Enabling SASL Authentication on SSL/TLS

When the Kafka cluster uses the SASL_SSL security protocol, enable the Kafka stage to use SASL authentication on SSL/TLS.

Before you enable Kafka stages to use SASL authentication on SSL/TLS, make sure that you have performed all necessary prerequisite tasks.

To use a Java Authentication and Authorization Service (JAAS) file to provide plain or Kerberos credentials, create a JAAS configuration file on the Data Collector machine.

The contents of the JAAS configuration file depend on whether you use the PLAIN or GSSAPI (Kerberos) SASL mechanism and depend on your Data Collector installation and authentication type. For details, see Providing PLAIN Credentials or Providing Kerberos Credentials.
If using the GSSAPI (Kerberos) SASL mechanism and a credential store to call keytabs from stage properties, add the Base64-encoded keytabs that you want to use to the credential store.

Note: Be sure to remove unnecessary characters, such as newline characters, before encoding the keytab.

If you configured Data Collector to require group secrets, for each keytab secret that you define, create a group secret and specify a comma-separated list of groups allowed to access the keytab secret.

Name the group secret based on the keytab secret name, as follows: <keytab secret name>-groups.

For details on defining secrets, see your credential store documentation.
On the General tab of the Kafka stage, set the Stage Library property to the appropriate Kafka version.

If using stage properties to define Kafka credentials, select a stage library for Kafka version 0.11.0.0 or later.

On the Security tab of the stage, configure the following properties:


Security Property	Description
Security Option	Set to SASL Authentication on SSL/TLS (Security Protocol=SASL_SSL).
SASL Mechanism	SASL mechanism to use: PLAIN GSSAPI (Kerberos)
Kerberos Service Name	Kerberos service principal name that the Kafka brokers run as. Available when using the GSSAPI (Kerberos) mechanism.
Provide Keytab at Runtime	Enables providing Kerberos credentials in the connection properties. Important: Configuring Kerberos credentials in connection properties is not supported in Transformer pipelines at this time. Available when using the GSSAPI (Kerberos) mechanism.
Runtime Keytab	Kerberos keytab to use for the connection, specified in one of the following ways: Enter a Base64-encoded keytab. Be sure to remove unnecessary characters, such as newline characters, before encoding the keytab. If using a credential store, use the `credential:get()` or `credential:getWithOptions()` credential function to retrieve a Base64-encoded keytab. Note: The user who starts the pipeline must be in the Data Collector group specified in the credential function. When Data Collector requires a group secret, the user must also be in a group associated with the keytab. For more information about using keytabs in a credential store, see Using a Credential Store. Available when using the GSSAPI (Kerberos) mechanism.
Runtime Principal	Kerberos principal to use for the connection, specified in the following format: `<principal name>/<host name>@<realm>`. Available when using the GSSAPI (Kerberos) mechanism.
Truststore File	Path to the truststore file. Enter an absolute path to the file or enter the following expression to define the file stored in the Data Collector resources directory: `${runtime:resourcesDirPath()}/keystore.jks`
Truststore Password	Password to the truststore file. Tip: To secure sensitive information such as passwords, you can use runtime resources or credential stores.
Enabled Protocols	Comma-separated list of protocols used to connect to the Kafka brokers. Ensure that at least one of these protocols is enabled in the Kafka brokers. Note: Older protocols are not as secure as TLSv1.2.
Truststore Type	Type of truststore to use. Use one of the following types: Java Keystore File (JKS) PKCS #12 (p12 file) Default is Java Keystore File (JKS).

Enabling Custom Authentication

To specify security requirements with custom properties, enable the Kafka stage to use custom authentication.

With custom authentication, you specify custom properties that contain the information required by the security protocol rather than using the properties in the stage. For example, you can enable custom authentication and then configure custom properties required for the SASL_SSL security protocol rather than enabling SASL Authentication on SSL/TLS.

Before enabling custom authentication, complete any necessary prerequisites for the security methods you are using, as described in the Kafka documentation. For example, if using SSL/TLS to connect to Kafka, you must make sure Kafka is configured for SSL/TLS.

On the General tab of the stage, set the Stage Library property to the appropriate Kafka version.

On the Security tab, configure the following properties:


Security Property	Description
Security Option	Set to Custom Authentication (Security Protocol=CUSTOM).
Custom Security Properties	Additional security properties to use. In simple or bulk edit mode, click the Add icon to add properties. Define the security property name and value. Use the property names and values as expected for Kafka clients. For more information, see the Kafka documentation.

For example, to configure the SASL_SSL security protocol with the PLAIN mechanism, in Custom Security Properties you configure properties to set the protocol, to connect to the Java Authentication and Authorization Service (JAAS), and to use SSL/TLS:


Name	Value
security.protocol	`SASL_SSL`
sasl.mechanism	`PLAIN`
sasl.jaas.config	`org.apache.kafka.common.security.plain.PlainLoginModule required \ username="<user name for JAAS>"\ password="<password>";`
ssl.truststore.location	`<full path to the client truststore jks file>`
ssl.truststore.password	`<password>`