AWS SDK Version 3 for .NET
API Reference

AWS services or capabilities described in AWS Documentation may vary by region/location. Click Getting Started with Amazon AWS to see specific differences applicable to the China (Beijing) Region.

Container for the parameters to the GenerateDataKeyWithoutPlaintext operation. Returns a data encryption key encrypted under a customer master key (CMK). This operation is identical to GenerateDataKey but returns only the encrypted copy of the data key.

To perform this operation on a CMK in a different AWS account, specify the key ARN or alias ARN in the value of the KeyId parameter.

This operation is useful in a system that has multiple components with different degrees of trust. For example, consider a system that stores encrypted data in containers. Each container stores the encrypted data and an encrypted copy of the data key. One component of the system, called the control plane, creates new containers. When it creates a new container, it uses this operation (GenerateDataKeyWithoutPlaintext) to get an encrypted data key and then stores it in the container. Later, a different component of the system, called the data plane, puts encrypted data into the containers. To do this, it passes the encrypted data key to the Decrypt operation. It then uses the returned plaintext data key to encrypt data and finally stores the encrypted data in the container. In this system, the control plane never sees the plaintext data key.

The result of this operation varies with the key state of the CMK. For details, see How Key State Affects Use of a Customer Master Key in the AWS Key Management Service Developer Guide.

Inheritance Hierarchy


Namespace: Amazon.KeyManagementService.Model
Assembly: AWSSDK.KeyManagementService.dll
Version: 3.x.y.z


public class GenerateDataKeyWithoutPlaintextRequest : AmazonKeyManagementServiceRequest

The GenerateDataKeyWithoutPlaintextRequest type exposes the following members



Public Property EncryptionContext System.Collections.Generic.Dictionary<System.String, System.String>

Gets and sets the property EncryptionContext.

A set of key-value pairs that represents additional authenticated data.

For more information, see Encryption Context in the AWS Key Management Service Developer Guide.

Public Property GrantTokens System.Collections.Generic.List<System.String>

Gets and sets the property GrantTokens.

A list of grant tokens.

For more information, see Grant Tokens in the AWS Key Management Service Developer Guide.

Public Property KeyId System.String

Gets and sets the property KeyId.

The identifier of the customer master key (CMK) under which to generate and encrypt the data encryption key.

To specify a CMK, use its key ID, Amazon Resource Name (ARN), alias name, or alias ARN. When using an alias name, prefix it with "alias/". To specify a CMK in a different AWS account, you must use the key ARN or alias ARN.

For example:

  • Key ID: 1234abcd-12ab-34cd-56ef-1234567890ab

  • Key ARN: arn:aws:kms:us-east-2:111122223333:key/1234abcd-12ab-34cd-56ef-1234567890ab

  • Alias name: alias/ExampleAlias

  • Alias ARN: arn:aws:kms:us-east-2:111122223333:alias/ExampleAlias

To get the key ID and key ARN for a CMK, use ListKeys or DescribeKey. To get the alias name and alias ARN, use ListAliases.

Public Property KeySpec Amazon.KeyManagementService.DataKeySpec

Gets and sets the property KeySpec.

The length of the data encryption key. Use AES_128 to generate a 128-bit symmetric key, or AES_256 to generate a 256-bit symmetric key.

Public Property NumberOfBytes System.Int32

Gets and sets the property NumberOfBytes.

The length of the data encryption key in bytes. For example, use the value 64 to generate a 512-bit data key (64 bytes is 512 bits). For common key lengths (128-bit and 256-bit symmetric keys), we recommend that you use the KeySpec field instead of this one.


The following example generates an encrypted copy of a 256-bit symmetric data encryption key (data key). The data key is encrypted with the specified customer master key (CMK).

To generate an encrypted data key

var response = client.GenerateDataKeyWithoutPlaintext(new GenerateDataKeyWithoutPlaintextRequest 
    KeyId = "alias/ExampleAlias", // The identifier of the CMK to use to encrypt the data key. You can use the key ID or Amazon Resource Name (ARN) of the CMK, or the name or ARN of an alias that refers to the CMK.
    KeySpec = "AES_256" // Specifies the type of data key to return.

MemoryStream ciphertextBlob = response.CiphertextBlob; // The encrypted data key.
string keyId = response.KeyId; // The ARN of the CMK that was used to encrypt the data key.


Version Information

.NET Standard:
Supported in: 1.3

.NET Framework:
Supported in: 4.5, 4.0, 3.5

Portable Class Library:
Supported in: Windows Store Apps
Supported in: Windows Phone 8.1
Supported in: Xamarin Android
Supported in: Xamarin iOS (Unified)
Supported in: Xamarin.Forms