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Key Management Service:AsymmetricDecrypt

更新時間:Sep 13, 2024

Decrypts data by using an asymmetric key.

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:

Limits

You can call this operation up to 200 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

This operation supports only asymmetric keys for which Usage is set to ENCRYPT/DECRYPT. The following table lists supported encryption algorithms.

KeySpec

Algorithm

Description

Maximum length in bytes

RSA_2048

RSAES_OAEP_SHA_256

RSAES-OAEP using SHA-256 and MGF1 with SHA-256

256

RSA_2048

RSAES_OAEP_SHA_1

RSAES-OAEP using SHA1 and MGF1 with SHA1

256

RSA_3072

RSAES_OAEP_SHA_256

RSAES-OAEP using SHA-256 and MGF1 with SHA-256

384

RSA_3072

RSAES_OAEP_SHA_1

RSAES-OAEP using SHA1 and MGF1 with SHA1

384

EC_SM2

SM2PKE

SM2 public key encryption algorithm based on elliptic curves

6144

In this example, an asymmetric key whose ID is hzz630494463ejqjx**** andversion ID is 2ab1a983-7072-4bbc-a582-584b5bd8**** and the RSAES_OAEP_SHA_1 algorithm are used to decrypt the ciphertext BQKP+1zK6+ZEMxTP5qaVzcsgXtWplYBKm0NXdSnB5FzliFxE1bSiu4dnEIlca2JpeH7yz1/S6fed630H+hIH6DoM25fTLNcKj+mFB0Xnh9m2+HN59Mn4qyTfcUeadnfCXSWcGBouhXFwcdd2rJ3n337bzTf4jm659gZu3L0i6PLuxM9p7mqdwO0cKJPfGVfhnfMz+f4alMg79WB/NNyE2lyX7/qxvV49ObNrrJbKSFiz8Djocaf0IESNLMbfYI5bXjWkJlX92DQbKhibtQW8ZOJ//ZC6t0AWcUoKL6QDm/dg5koQalcleRinpB+QadFm894sLbVZ9+N4GVsv1W****==.

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 AsymmetricDecrypt

The operation that you want to perform. Set the value to AsymmetricDecrypt.

CiphertextBlob String Yes BQKP+1zK6+ZEMxTP5qaVzcsgXtWplYBKm0NXdSnB5FzliFxE1bSiu4dnEIlca2JpeH7yz1/S6fed630H+hIH6DoM25fTLNcKj+mFB0Xnh9m2+HN59Mn4qyTfcUeadnfCXSWcGBouhXFwcdd2rJ3n337bzTf4jm659gZu3L0i6PLuxM9p7mqdwO0cKJPfGVfhnfMz+f4alMg79WB/NNyE2lyX7/qxvV49ObNrrJbKSFiz8Djocaf0IESNLMbfYI5bXjWkJlX92DQbKhibtQW8ZOJ//ZC6t0AWcUoKL6QDm/dg5koQalcleRinpB+QadFm894sLbVZ9+N4GVsv1W****==

The Base64-encoded ciphertext that you want to decrypt.

Note You can call the AsymmetricEncrypt operation to generate ciphertext.
KeyId String Yes key-hzz630494463ejqjx****

The ID, alias, or Alibaba Cloud Resource Name (ARN) of the key. For more information, see Manage a key alias.

Note When you access a key within another Alibaba Cloud account, you must enter the ARN of the key. The ARN of the key is in the acs:kms:${region}:${account}:key/${keyid} format.
KeyVersionId String Yes 2ab1a983-7072-4bbc-a582-584b5bd8****

The version ID of the key. The ID must be globally unique.

Algorithm String Yes RSAES_OAEP_SHA_1

The decryption algorithm.

DryRun String No false

Specifies whether to perform a dry run. Valid values:

  • true
  • false (default)

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:

  • DryRunOperationError: The request passes the dry run. If you do not configure the DryRun parameter and retain the other parameter configurations to call the same operation, the operation will be performed.
  • ValidationError: A parameter value in the request is invalid.
  • AccessDeniedError: You do not have the permissions to access the resources that you want to manage.

Response parameters

Parameter

Type

Example

Description

KeyVersionId String 2ab1a983-7072-4bbc-a582-584b5bd8****

The version ID of the key that is used to encrypt the plaintext.

KeyId String key-hzz630494463ejqjx****

The ID of the key. If KeyId is set to the alias or ARN of the key, the ID of the key is returned.

RequestId String 475f1620-b9d3-4d35-b5c6-3fbdd941423d

The request ID.

Plaintext String SGVsbG8gd29ybGQ=

The Base64-encoded plaintext that is generated after decryption.

Examples

Sample requests

http(s)://[Endpoint]/?Action=AsymmetricDecrypt
&CiphertextBlob=BQKP+1zK6+ZEMxTP5qaVzcsgXtWplYBKm0NXdSnB5FzliFxE1bSiu4dnEIlca2JpeH7yz1/S6fed630H+hIH6DoM25fTLNcKj+mFB0Xnh9m2+HN59Mn4qyTfcUeadnfCXSWcGBouhXFwcdd2rJ3n337bzTf4jm659gZu3L0i6PLuxM9p7mqdwO0cKJPfGVfhnfMz+f4alMg79WB/NNyE2lyX7/qxvV49ObNrrJbKSFiz8Djocaf0IESNLMbfYI5bXjWkJlX92DQbKhibtQW8ZOJ//ZC6t0AWcUoKL6QDm/dg5koQalcleRinpB+QadFm894sLbVZ9+N4GVsv1W****==
&KeyId=key-hzz630494463ejqjx****
&KeyVersionId=2ab1a983-7072-4bbc-a582-584b5bd8****
&Algorithm=RSAES_OAEP_SHA_1
&DryRun=false
&<Common request parameters>

Sample success responses

XML format

HTTP/1.1 200 OK
Content-Type:application/xml

<AsymmetricDecryptResponse>
    <KeyVersionId>2ab1a983-7072-4bbc-a582-584b5bd8****</KeyVersionId>
    <KeyId>key-hzz630494463ejqjx****</KeyId>
    <RequestId>475f1620-b9d3-4d35-b5c6-3fbdd941423d</RequestId>
    <Plaintext>SGVsbG8gd29ybGQ=</Plaintext>
</AsymmetricDecryptResponse>

JSON format

HTTP/1.1 200 OK
Content-Type:application/json

{
  "KeyVersionId" : "2ab1a983-7072-4bbc-a582-584b5bd8****",
  "KeyId" : "key-hzz630494463ejqjx****",
  "RequestId" : "475f1620-b9d3-4d35-b5c6-3fbdd941423d",
  "Plaintext" : "SGVsbG8gd29ybGQ="
}

Error codes

HttpCode

Error code

Error message

Description

400 Rejected.UnsupportedOperation Unsupported operation. The operation is not supported.
404 Forbidden.AliasNotFound The specified Alias is not found. The specified alias is not found.
404 Forbidden.KeyNotFound The specified Key is not found. The specified key does not exist.

For a list of error codes, see Service error codes.