AWS SDK Version 3 for .NET
API Reference

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Container for the parameters to the ReEncrypt operation. Encrypts data on the server side with a new customer master key (CMK) without exposing the plaintext of the data on the client side. The data is first decrypted and then reencrypted. You can also use this operation to change the encryption context of a ciphertext.

You can reencrypt data using CMKs in different AWS accounts.

Unlike other operations, ReEncrypt is authorized twice, once as ReEncryptFrom on the source CMK and once as ReEncryptTo on the destination CMK. We recommend that you include the "kms:ReEncrypt*" permission in your key policies to permit reencryption from or to the CMK. This permission is automatically included in the key policy when you create a CMK through the console. But you must include it manually when you create a CMK programmatically or when you set a key policy with the PutKeyPolicy operation.

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 ReEncryptRequest : AmazonKeyManagementServiceRequest

The ReEncryptRequest type exposes the following members


Public Method ReEncryptRequest()


Public Property CiphertextBlob System.IO.MemoryStream

Gets and sets the property CiphertextBlob.

Ciphertext of the data to reencrypt.

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

Gets and sets the property DestinationEncryptionContext.

Encryption context to use when the data is reencrypted.

Public Property DestinationKeyId System.String

Gets and sets the property DestinationKeyId.

A unique identifier for the CMK that is used to reencrypt the data.

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 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 SourceEncryptionContext System.Collections.Generic.Dictionary<System.String, System.String>

Gets and sets the property SourceEncryptionContext.

Encryption context used to encrypt and decrypt the data specified in the CiphertextBlob parameter.


The following example reencrypts data with the specified CMK.

To reencrypt data

var response = client.ReEncrypt(new ReEncryptRequest 
    CiphertextBlob = new MemoryStream(), // The data to reencrypt.
    DestinationKeyId = "0987dcba-09fe-87dc-65ba-ab0987654321" // The identifier of the CMK to use to reencrypt the data. 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.

MemoryStream ciphertextBlob = response.CiphertextBlob; // The reencrypted data.
string keyId = response.KeyId; // The ARN of the CMK that was used to reencrypt the data.
string sourceKeyId = response.SourceKeyId; // The ARN of the CMK that was used to originally encrypt the data.


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