Re-encrypts ciphertext. When you call this operation, Key Management Service (KMS) decrypts the ciphertext, uses a different key to re-encrypt the generated plaintext or data key, and then returns the new ciphertext.
Usage notes
- Keys outside Key Management Service (KMS) instances: To perform cryptographic operations, use Alibaba Cloud SDK to call operations.
- Keys in KMS instances: To perform cryptographic operations, use one of the following methods:
- Method 1 (recommended): Use KMS Instance SDK to call KMS Instance API operations. For more information, see KMS Instance SDK and KMS Instance API.
- Method 2: Use Alibaba Cloud SDK to call operations. The authentication method supports only RAM roles whose trusted entities are Alibaba Cloud services. For more information, see Create a RAM role for a trusted Alibaba Cloud service.
Limits
You can call this operation up to 750 times per second per account. If the number of calls per second exceeds the limit, throttling is triggered. As a result, your business may be affected. We recommend that you take note of the limit when you call this operation.
Description
You can call this operation in the following scenarios:
- After a key that was used to encrypt your data is rotated, you can call this operation to use the latest key version to re-encrypt the data. For more information about automatic key rotation, see Configure automatic key rotation.
- The key that was used to encrypt your data remains unchanged, but EncryptionContext is changed. In this scenario, you can call this operation to re-encrypt the data.
- You can call this operation to use a key in KMS to re-encrypt data or a data key that was previously encrypted by using a different key.
To call the ReEncrypt operation, you must have the following permissions:
- The kms:ReEncryptFrom permission on the source key
- The kms:ReEncryptTo permission on the destination key
- For simplicity, you can specify kms:ReEncrypt* to allow both of the preceding permissions.
Debugging
Request parameters
|
Parameter |
Type |
Required |
Example |
Description |
| Action | String | Yes | ReEncrypt | The operation that you want to perform. Set the value to ReEncrypt. |
| CiphertextBlob | String | Yes | ODZhOWVmZDktM2QxNi00ODk0LWJkNGYtMWZjNDNmM2YyYWJmS7FmDBBQ0BkKsQrtRnidtPwirmDcS0ZuJCU41xxAAWk4Z8qsADfbV0b+i6kQmlvj79dJdGOvtX69Uycs901q******** | The ciphertext that you want to re-encrypt. You can set this parameter to the ciphertext that is returned after symmetric or asymmetric encryption.
|
| SourceKeyId | String | No | 5c438b18-05be-40ad-b6c2-3be6752c**** | The ID of the key that is used to decrypt the ciphertext. The ID must be globally unique. Note If you set CiphertextBlob to the public key-encrypted ciphertext that is returned after asymmetric encryption, specify this parameter. |
| SourceKeyVersionId | String | No | 2ab1a983-7072-4bbc-a582-584b5bd8**** | The version ID of the key that is used to decrypt the ciphertext. Note If you set CiphertextBlob to the public key-encrypted ciphertext that is returned after asymmetric encryption, specify this parameter. |
| SourceEncryptionAlgorithm | String | No | RSAES_OAEP_SHA_256 | The encryption algorithm that is used by the public key when CiphertextBlob is set to the public key-encrypted ciphertext. For more information about encryption algorithms, see AsymmetricDecrypt. Valid values:
Note If you set CiphertextBlob to the public key-encrypted ciphertext that is returned after asymmetric encryption, specify this parameter. |
| SourceEncryptionContext | Map | No | {"Example":"Example"} | The JSON string that consists of key-value pairs. If you specify this parameter when you call the Encrypt, GenerateDataKey, GenerateDataKeyWithoutPlaintext, or GenerateAndExportDataKey operation, you must specify the same value for this parameter when you call the ReEncrypt operation. For more information, see EncryptionContext. Note If you set CiphertextBlob to the ciphertext that is returned after symmetric encryption, specify this parameter. |
| DestinationKeyId | String | Yes | 1234abcd-12ab-34cd-56ef-12345678**** | The ID of the symmetric key that is used to re-encrypt the decrypted data or data key after the ciphertext is decrypted. |
| DestinationEncryptionContext | Map | No | {"Example":"Example"} | A JSON string that consists of key-value pairs. This parameter specifies the encryption context that is used to re-encrypt the decrypted data or data key. |
| DryRun | String | No | false | Specifies whether to perform a dry run. Valid values:
A dry run is used for testing in API calls. You can perform a dry run to check whether you have the permissions to access the resources that you want to manage and whether the request parameters are correctly configured. If you set DryRun to true in the request, KMS always returns an error code that indicates the cause of the error. KMS may return the following error codes:
|
Response parameters
Parameter |
Type |
Example |
Description |
| KeyId | String | 2ab1a983-7072-4bbc-a582-584b5bd8**** | The ID of the key that is used to decrypt the ciphertext. The ID must be globally unique. |
| KeyVersionId | String | 202b9877-5a25-46e3-a763-e20791b5**** | The version ID of the key that is used to decrypt the ciphertext. |
| CiphertextBlob | String | DZhOWVmZDktM2QxNi00ODk0LWJkNGYtMWZjNDNmM2YyYWJmaaSl+TztSIMe43nbTH/Z1Wr4XfLftKhAciUmDQXuMRl4WTvKhxjMThjK**** | The new ciphertext. |
| RequestId | String | 207596a2-36d3-4840-b1bd-f87044699bd7 | The request ID. |
Examples
Sample requests
http(s)://[Endpoint]/?Action=ReEncrypt
&CiphertextBlob=ODZhOWVmZDktM2QxNi00ODk0LWJkNGYtMWZjNDNmM2YyYWJmS7FmDBBQ0BkKsQrtRnidtPwirmDcS0ZuJCU41xxAAWk4Z8qsADfbV0b+i6kQmlvj79dJdGOvtX69Uycs901q********
&SourceKeyId=5c438b18-05be-40ad-b6c2-3be6752c****
&SourceKeyVersionId=2ab1a983-7072-4bbc-a582-584b5bd8****
&SourceEncryptionAlgorithm=RSAES_OAEP_SHA_256
&DestinationKeyId=1234abcd-12ab-34cd-56ef-12345678****
&DryRun=false
&<Common request parameters>Sample success responses
XML format
HTTP/1.1 200 OK
Content-Type:application/xml
<ReEncryptResponse>
<KeyId>2ab1a983-7072-4bbc-a582-584b5bd8****</KeyId>
<KeyVersionId>202b9877-5a25-46e3-a763-e20791b5****</KeyVersionId>
<CiphertextBlob>DZhOWVmZDktM2QxNi00ODk0LWJkNGYtMWZjNDNmM2YyYWJmaaSl+TztSIMe43nbTH/Z1Wr4XfLftKhAciUmDQXuMRl4WTvKhxjMThjK****</CiphertextBlob>
<RequestId>207596a2-36d3-4840-b1bd-f87044699bd7</RequestId>
</ReEncryptResponse>JSON format
HTTP/1.1 200 OK
Content-Type:application/json
{
"KeyId" : "2ab1a983-7072-4bbc-a582-584b5bd8****",
"KeyVersionId" : "202b9877-5a25-46e3-a763-e20791b5****",
"CiphertextBlob" : "DZhOWVmZDktM2QxNi00ODk0LWJkNGYtMWZjNDNmM2YyYWJmaaSl+TztSIMe43nbTH/Z1Wr4XfLftKhAciUmDQXuMRl4WTvKhxjMThjK****",
"RequestId" : "207596a2-36d3-4840-b1bd-f87044699bd7"
}Error codes
|
HttpCode |
Error code |
Error message |
Description |
| 400 | InvalidParameter | The specified parameter is not valid. | The specified parameter is invalid. |
| 404 | Forbidden.KeyNotFound | The specified Key is not found. | The specified key does not exist. |
| 500 | InternalFailure | Internal Failure. | An internal error occurred. Try again later. If the error persists, submit a ticket. |
For a list of error codes, see Service error codes.