There are more AWS SDK examples available in the [AWS Doc SDK Examples](https://github.com/awsdocs/aws-doc-sdk-examples) GitHub repo. # Use `GenerateDataKey` with an AWS SDK or CLI The following code examples show how to use `GenerateDataKey`. ------ #### [ CLI ] **AWS CLI** **Example 1: To generate a 256-bit symmetric data key** The following `generate-data-key` example requests a 256-bit symmetric data key for use outside of AWS. The command returns a plaintext data key for immediate use and deletion, and a copy of that data key encrypted under the specified KMS key. You can safely store the encrypted data key with the encrypted data. To request a 256-bit data key, use the `key-spec` parameter with a value of `AES_256`. To request a 128-bit data key, use the `key-spec` parameter with a value of `AES_128`. For all other data key lengths, use the `number-of-bytes` parameter. The KMS key you specify must be a symmetric encryption KMS key, that is, a KMS key with a key spec value of SYMMETRIC\$1DEFAULT. ``` aws kms generate-data-key \ --key-id alias/ExampleAlias \ --key-spec AES_256 ``` Output: ``` { "Plaintext": "VdzKNHGzUAzJeRBVY+uUmofUGGiDzyB3+i9fVkh3piw=", "KeyId": "arn:aws:kms:us-east-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab", "KeyMaterialId": "0b7fd7ddbac6eef27907413567cad8c810e2883dc8a7534067a82ee1142fc1e6", "CiphertextBlob": "AQEDAHjRYf5WytIc0C857tFSnBaPn2F8DgfmThbJlGfR8P3WlwAAAH4wfAYJKoZIhvcNAQcGoG8wbQIBADBoBgkqhkiG9w0BBwEwHgYJYIZIAWUDBAEuMBEEDEFogLqPWZconQhwHAIBEIA7d9AC7GeJJM34njQvg4Wf1d5sw0NIo1MrBqZa+YdhV8MrkBQPeac0ReRVNDt9qleAt+SHgIRF8P0H+7U=" } ``` The `Plaintext` (plaintext data key) and the `CiphertextBlob` (encrypted data key) are returned in base64-encoded format. For more information, see [Data keys](https://docs.aws.amazon.com/kms/latest/developerguide/data-keys.html) in the *AWS Key Management Service Developer Guide*. **Example 2: To generate a 512-bit symmetric data key** The following `generate-data-key` example requests a 512-bit symmetric data key for encryption and decryption. The command returns a plaintext data key for immediate use and deletion, and a copy of that data key encrypted under the specified KMS key. You can safely store the encrypted data key with the encrypted data. To request a key length other than 128 or 256 bits, use the `number-of-bytes` parameter. To request a 512-bit data key, the following example uses the `number-of-bytes` parameter with a value of 64 (bytes). The KMS key you specify must be a symmetric encryption KMS key, that is, a KMS key with a key spec value of SYMMETRIC\$1DEFAULT. NOTE: The values in the output of this example are truncated for display. ``` aws kms generate-data-key \ --key-id 1234abcd-12ab-34cd-56ef-1234567890ab \ --number-of-bytes 64 ``` Output: ``` { "CiphertextBlob": "AQIBAHi6LtupRpdKl2aJTzkK6FbhOtQkMlQJJH3PdtHvS/y+hAEnX/QQNmMwDfg2korNMEc8AAACaDCCAmQGCSqGSIb3DQEHBqCCAlUwggJRAgEAMIICSgYJKoZ...", "Plaintext": "ty8Lr0Bk6OF07M2BWt6qbFdNB+G00ZLtf5MSEb4al3R2UKWGOp06njAwy2n72VRm2m7z/Pm9Wpbvttz6a4lSo9hgPvKhZ5y6RTm4OovEXiVfBveyX3DQxDzRSwbKDPk/...", "KeyId": "arn:aws:kms:us-west-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab", "KeyMaterialId": "0b7fd7ddbac6eef27907413567cad8c810e2883dc8a7534067a82ee1142fc1e6" } ``` The `Plaintext` (plaintext data key) and `CiphertextBlob` (encrypted data key) are returned in base64-encoded format. For more information, see [Data keys](https://docs.aws.amazon.com/kms/latest/developerguide/data-keys.html) in the *AWS Key Management Service Developer Guide*. + For API details, see [GenerateDataKey](https://awscli.amazonaws.com/v2/documentation/api/latest/reference/kms/generate-data-key.html) in *AWS CLI Command Reference*. ------ #### [ Python ] **SDK for Python (Boto3)** There's more on GitHub. Find the complete example and learn how to set up and run in the [AWS Code Examples Repository](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/python/example_code/kms#code-examples). ``` class KeyManager: def __init__(self, kms_client): self.kms_client = kms_client self.created_keys = [] @classmethod def from_client(cls) -> "KeyManager": """ Creates a KeyManager instance with a default KMS client. :return: An instance of KeyManager initialized with the default KMS client. """ kms_client = boto3.client("kms") return cls(kms_client) def generate_data_key(self, key_id): """ Generates a symmetric data key that can be used for client-side encryption. """ answer = input( f"Do you want to generate a symmetric data key from key {key_id} (y/n)? " ) if answer.lower() == "y": try: data_key = self.kms_client.generate_data_key( KeyId=key_id, KeySpec="AES_256" ) except ClientError as err: logger.error( "Couldn't generate a data key for key %s. Here's why: %s", key_id, err.response["Error"]["Message"], ) else: pprint(data_key) ``` + For API details, see [GenerateDataKey](https://docs.aws.amazon.com/goto/boto3/kms-2014-11-01/GenerateDataKey) in *AWS SDK for Python (Boto3) API Reference*. ------ #### [ Rust ] **SDK for Rust** There's more on GitHub. Find the complete example and learn how to set up and run in the [AWS Code Examples Repository](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/rustv1/examples/kms#code-examples). ``` async fn make_key(client: &Client, key: &str) -> Result<(), Error> { let resp = client .generate_data_key() .key_id(key) .key_spec(DataKeySpec::Aes256) .send() .await?; // Did we get an encrypted blob? let blob = resp.ciphertext_blob.expect("Could not get encrypted text"); let bytes = blob.as_ref(); let s = base64::encode(bytes); println!(); println!("Data key:"); println!("{}", s); Ok(()) } ``` + For API details, see [GenerateDataKey](https://docs.rs/aws-sdk-kms/latest/aws_sdk_kms/client/struct.Client.html#method.generate_data_key) in *AWS SDK for Rust API reference*. ------ #### [ SAP ABAP ] **SDK for SAP ABAP** There's more on GitHub. Find the complete example and learn how to set up and run in the [AWS Code Examples Repository](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/sap-abap/services/kms#code-examples). ``` TRY. " iv_key_id = 'arn:aws:kms:us-east-1:123456789012:key/1234abcd-12ab-34cd-56ef-1234567890ab' " iv_keyspec = 'AES_256' oo_result = lo_kms->generatedatakey( iv_keyid = iv_key_id iv_keyspec = 'AES_256' ). MESSAGE 'Data key generated successfully.' TYPE 'I'. CATCH /aws1/cx_kmsdisabledexception. MESSAGE 'The key is disabled.' TYPE 'E'. CATCH /aws1/cx_kmsnotfoundexception. MESSAGE 'Key not found.' TYPE 'E'. CATCH /aws1/cx_kmskmsinternalex. MESSAGE 'An internal error occurred.' TYPE 'E'. ENDTRY. ``` + For API details, see [GenerateDataKey](https://docs.aws.amazon.com/sdk-for-sap-abap/v1/api/latest/index.html) in *AWS SDK for SAP ABAP API reference*. ------