AsymmetricSign - Key Management Service

Generates a signature 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:
- 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 Resource Access Management (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 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 SIGN/VERIFY. The following table describes the supported signature algorithms.

KeySpec	Algorithm	Description
RSA_2048	RSA_PSS_SHA_256	RSASSA-PSS using SHA-256 and MGF1 with SHA-256
RSA_2048	RSA_PKCS1_SHA_256	RSASSA-PKCS1-v1_5 using SHA-256
RSA_3072	RSA_PSS_SHA_256	RSASSA-PSS using SHA-256 and MGF1 with SHA-256
RSA_3072	RSA_PKCS1_SHA_256	RSASSA-PKCS1-v1_5 using SHA-256
EC_P256	ECDSA_SHA_256	ECDSA on the P-256 Curve(secp256r1) with a SHA-256 digest
EC_P256K	ECDSA_SHA_256	ECDSA on the P-256K Curve(secp256k1) with a SHA-256 digest
EC_SM2	SM2DSA	SM2 digital signature algorithm based on elliptic curves

Note

According to GB/T 32918.2 "Information security technology-Public key cryptographic algorithm SM2 based on elliptic curves-Part 2: Digital signature algorithm", when you calculate the SM2 signature, Digest is used to calculate the digest value of the combination of Z(A) and M, rather than the SM3 digest value. M indicates the original message that you want to sign. Z(A) indicates the hash value for User A. The hash value is defined in GB/T 32918.2.

In this example, the asymmetric key whose ID is 5c438b18-05be-40ad-b6c2-3be6752c**** and version ID is 2ab1a983-7072-4bbc-a582-584b5bd8**** and the RSA_PSS_SHA_256 signature algorithm are used to generate a signature for the ZOyIygCyaOW6GjVnihtTFtIS9PNmskdyMlNKiuy****= digest.

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	AsymmetricSign	The operation that you want to perform. Set the value to AsymmetricSign.
KeyId	String	Yes	5c438b18-05be-40ad-b6c2-3be6752c****	The ID of the key. The ID must be globally unique. Note You can also set this parameter to an alias that is bound to the key. For more information, see Alias overview.
KeyVersionId	String	Yes	2ab1a983-7072-4bbc-a582-584b5bd8****	The version ID of the key. The ID must be globally unique.
Algorithm	String	Yes	RSA_PSS_SHA_256	The signature algorithm.
Digest	String	Yes	ZOyIygCyaOW6GjVnihtTFtIS9PNmskdyMlNKiu****=	The digest that is generated for the original data by using a hash algorithm. The hash algorithm is specified by Algorithm. Note The value must be encoded in Base64. For more information about how to calculate message digests, see the Preprocess before signing: Compute a message digest section of the Generate and verify a digital signature by using an asymmetric CMK topic.
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. The ID must be globally unique.
KeyId	String	5c438b18-05be-40ad-b6c2-3be6752c****	The ID of the key. The ID must be globally unique. Note If you set KeyId in the request to an alias, the ID of the key to which the alias is bound is returned.
Value	String	M2CceNZH00ZgL9ED/ZHFp21YRAvYeZHknJUc207OCZ0N9wNn9As4z2bON3FF3je+1Nu+2+/8Zj50HpMTpzYpMp2R93cYmACCmhaYoKydxylbyGzJR8y9likZRCrkD38lRoS40aBBvv/6iRKzQuo9EGYVcel36cMNg00VmYNBy3pa1rwg3gA4l3cy6kjayZja1WGPkVhrVKsrJMdbpl0ApLjXKuD8rw1n1XLCwCUEL5eLPljTZaAveqdOFQOiZnZEGI27qIiZe7I1fN8tcz6anS/gTM7xRKE++5egEvRWlTQQTJeApnPSiUPA+8ZykNdelQsOQh5SrGoyI4A5pq****==	The calculated signature. Note The value must be encoded in Base64.
RequestId	String	475f1620-b9d3-4d35-b5c6-3fbdd941423d	The request ID.

Examples

Sample requests

http(s)://[Endpoint]/?Action=AsymmetricSign
&KeyId=5c438b18-05be-40ad-b6c2-3be6752c****
&KeyVersionId=2ab1a983-7072-4bbc-a582-584b5bd8****
&Algorithm=RSA_PSS_SHA_256
&Digest=ZOyIygCyaOW6GjVnihtTFtIS9PNmskdyMlNKiu****=
&DryRun=false
&<Common request parameters>

Sample success responses

XML format

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

<AsymmetricSignResponse>
    <KeyVersionId>2ab1a983-7072-4bbc-a582-584b5bd8****</KeyVersionId>
    <KeyId>5c438b18-05be-40ad-b6c2-3be6752c****</KeyId>
    <Value>M2CceNZH00ZgL9ED/ZHFp21YRAvYeZHknJUc207OCZ0N9wNn9As4z2bON3FF3je+1Nu+2+/8Zj50HpMTpzYpMp2R93cYmACCmhaYoKydxylbyGzJR8y9likZRCrkD38lRoS40aBBvv/6iRKzQuo9EGYVcel36cMNg00VmYNBy3pa1rwg3gA4l3cy6kjayZja1WGPkVhrVKsrJMdbpl0ApLjXKuD8rw1n1XLCwCUEL5eLPljTZaAveqdOFQOiZnZEGI27qIiZe7I1fN8tcz6anS/gTM7xRKE++5egEvRWlTQQTJeApnPSiUPA+8ZykNdelQsOQh5SrGoyI4A5pq****==</Value>
    <RequestId>475f1620-b9d3-4d35-b5c6-3fbdd941423d</RequestId>
</AsymmetricSignResponse>

JSON format

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

{
  "KeyVersionId" : "2ab1a983-7072-4bbc-a582-584b5bd8****",
  "KeyId" : "5c438b18-05be-40ad-b6c2-3be6752c****",
  "Value" : "M2CceNZH00ZgL9ED/ZHFp21YRAvYeZHknJUc207OCZ0N9wNn9As4z2bON3FF3je+1Nu+2+/8Zj50HpMTpzYpMp2R93cYmACCmhaYoKydxylbyGzJR8y9likZRCrkD38lRoS40aBBvv/6iRKzQuo9EGYVcel36cMNg00VmYNBy3pa1rwg3gA4l3cy6kjayZja1WGPkVhrVKsrJMdbpl0ApLjXKuD8rw1n1XLCwCUEL5eLPljTZaAveqdOFQOiZnZEGI27qIiZe7I1fN8tcz6anS/gTM7xRKE++5egEvRWlTQQTJeApnPSiUPA+8ZykNdelQsOQh5SrGoyI4A5pq****==",
  "RequestId" : "475f1620-b9d3-4d35-b5c6-3fbdd941423d"
}

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.
404	Forbidden.AliasNotFound	The specified Alias is not found.	The specified alias is not found.

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