ReEncrypt - Key Management Service - Alibaba Cloud Documentation Center

Usage notes

Keys outside 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.

QPS limits

You can call this operation up to 750 times per second per account. If the number of the 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

OpenAPI Explorer automatically calculates the signature value. For your convenience, we recommend that you call this operation in OpenAPI Explorer. OpenAPI Explorer dynamically generates the sample code of the operation for different SDKs.

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. You can set this parameter to the ciphertext that is returned after a symmetric or asymmetric encryption operation. Symmetric encryption: the ciphertext that is returned by calling the Encrypt, GenerateDataKey, GenerateDataKeyWithoutPlaintext, or GenerateAndExportDataKey operation. Asymmetric encryption: the public key-encrypted ciphertext that is returned by calling the GenerateAndExportDataKey operation or the ciphertext that is encrypted by an external system using the public key of an asymmetric key.
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 an asymmetric encryption operation, 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 an asymmetric encryption operation, specify this parameter.
SourceEncryptionAlgorithm	String	No	RSAES_OAEP_SHA_256	The encryption algorithm that is used by the public key to encrypt ciphertext when CiphertextBlob is set to the public key-encrypted ciphertext. For more information about encryption algorithms, see AsymmetricDecrypt. Valid values: RSAES_OAEP_SHA_256 RSAES_OAEP_SHA_1 SM2PKE Note If you set CiphertextBlob to the public key-encrypted ciphertext that is returned after an asymmetric encryption operation, specify this parameter.
SourceEncryptionContext	Map	No	{"Example":"Example"}	The JSON string that consists of key-value pairs. If you configure this parameter when you call the Encrypt, GenerateDataKey, GenerateDataKeyWithoutPlaintext, or GenerateAndExportDataKey operation, an equivalent value is required when you decrypt data. For more information, see EncryptionContext. Note If you set CiphertextBlob to the ciphertext that is returned after a symmetric encryption operation, 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.

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 ID of the request.

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****
&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

HTTP status code	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.