Data protection in Amazon Data Firehose
Amazon Data Firehose encrypts all data in transit using TLS protocol. Furthermore, for data stored in interim storage during processing, Amazon Data Firehose encrypts data using AWS Key Management Service and verifies data integrity using checksum verification.
If you have sensitive data, you can enable server-side data encryption when you use Amazon Data Firehose. How you do this depends on the source of your data.
Note
If you require FIPS 140-2 validated cryptographic modules when accessing AWS through a
command line interface or an API, use a FIPS endpoint. For more information about the
available FIPS endpoints, see Federal
Information Processing Standard (FIPS) 140-2
Server-side encryption with Kinesis Data Streams
When you send data from your data producers to your data stream, Kinesis Data Streams encrypts your data using an AWS Key Management Service (AWS KMS) key before storing the data at rest. When your Firehose stream reads the data from your data stream, Kinesis Data Streams first decrypts the data and then sends it to Amazon Data Firehose. Amazon Data Firehose buffers the data in memory based on the buffering hints that you specify. It then delivers it to your destinations without storing the unencrypted data at rest.
For information about how to enable server-side encryption for Kinesis Data Streams, see Using Server-Side Encryption in the Amazon Kinesis Data Streams Developer Guide.
Server-side encryption with Direct PUT or other data sources
If you send data to your Firehose stream using PutRecord or PutRecordBatch, or if you send the data using AWS IoT, Amazon CloudWatch Logs, or CloudWatch Events, you can turn on server-side encryption by using the StartDeliveryStreamEncryption operation.
To stop server-side-encryption, use the StopDeliveryStreamEncryption operation.
You can also enable SSE when you create the Firehose stream. To do that, specify DeliveryStreamEncryptionConfigurationInput when you invoke CreateDeliveryStream.
When the CMK is of type CUSTOMER_MANAGED_CMK, if the Amazon Data Firehose service is
unable to decrypt records because of a KMSNotFoundException, a
KMSInvalidStateException, a KMSDisabledException, or a
KMSAccessDeniedException, the service waits up to 24 hours (the
retention period) for you to resolve the problem. If the problem persists beyond the
retention period, the service skips those records that have passed the retention period
and couldn't be decrypted, and then discards the data. Amazon Data Firehose provides the following
four CloudWatch metrics that you can use to track the four AWS KMS exceptions:
-
KMSKeyAccessDenied -
KMSKeyDisabled -
KMSKeyInvalidState -
KMSKeyNotFound
For more information about these four metrics, see Monitor Amazon Data Firehose with CloudWatch metrics.
Important
To encrypt your Firehose stream, use symmetric CMKs. Amazon Data Firehose doesn't support asymmetric CMKs. For information about symmetric and asymmetric CMKs, see About Symmetric and Asymmetric CMKs in the AWS Key Management Service developer guide.
Note
When you use a customer managed key (CUSTOMER_MANAGED_CMK) to enable server-side encryption (SSE) for your Firehose stream, the Firehose service sets an encryption context whenever it uses your key. Since this encryption context represents an occurrence where a key owned by your AWS account was used, it is logged as part of AWS CloudTrail event logs for your AWS account. This encryption context is system generated by the Firehose service. Your application should not make any assumptions about the format or content of the encryption context set by the Firehose service.
