Generates a digital signature by using a specified certificate.

The signature algorithm in the request parameters must match the key type. The following table describes the mapping between signature algorithms and key types.


Key type









In this example, the certificate whose ID is 12345678-1234-1234-1234-12345678**** and the signature algorithm ECDSA_SHA_256 are used to generate a digital signature for the raw data VGhlIHF1aWNrIGJyb3duIGZveCBqdW1wcyBvdmVyIHRoZSBsYXp5IGRvZy4=.


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 CertificatePrivateKeySign

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

Algorithm String Yes ECDSA_SHA_256

The signature algorithm. Valid values:

  • RSA_PKCS1_SHA_256
  • RSA_PSS_SHA_256
  • ECDSA_SHA_256
  • SM2DSA
    Note The SM2DSA signature algorithm is supported only in regions where managed hardware security modules (HSMs) are used in mainland China. For more information, see Managed HSM overview.
CertificateId String Yes 12345678-1234-1234-1234-12345678****

The ID of the certificate. It is the globally unique identifier (GUID) of the certificate in Certificates Manager.

Message String Yes VGhlIHF1aWNrIGJyb3duIGZveCBqdW1wcyBvdmVyIHRoZSBsYXp5IGRvZy4=

The data to be signed.

The value must be encoded in Base64. For example, if the data to be signed in the hexadecimal format is [0x31, 0x32, 0x33, 0x34], set this parameter to the Base64-encoded value MTIzNA==.

If the MessageType parameter is set to RAW, the size of the data must be less than or equal to 4 KB.

If the size of the data is greater than 4 KB, you can set the MessageType parameter to DIGEST and set the Message parameter to the digest of the data. The digest is also called hash value. You can compute the digest of the data on an on-premises machine. Certificates Manager uses the digest that you compute in your own certificate application system. The message digest algorithm that you use must match the specified signature algorithm. Comply with the following mapping between signature algorithms and message digest algorithms:

  • If the signature algorithm is RSA_PKCS1_SHA_256, RSA_PSS_SHA_256, or ECDSA_SHA_256, the message digest algorithm must be SHA-256.
  • If the signature algorithm is SM2DSA, the message digest algorithm must be SM3.
Note If the key type of the certificate is EC_SM2 and the MessageType parameter is set to DIGEST, the value of the Message parameter is e that is described in GB/T 32918.2-2016 6.1.
MessageType String Yes RAW

The type of the message. Valid values:

  • RAW: the raw data. This is the default value.
  • DIGEST: the message digest (hash value) of the raw data.

For more information about common request parameters, see Common parameters.

Response parameters

Parameter Type Example Description
CertificateId String 12345678-1234-1234-1234-12345678****

The ID of the certificate.

RequestId String 5979d897-d69f-4fc9-87dd-f3bb73c40b80

The ID of the request.

SignatureValue String ZOyIygCyaOW6Gj****MlNKiuyjfzw=

The signature value.

The value is encoded in Base64.


Sample requests

&<Common request parameters>|

Sample success responses

XML format


JSON format

  "CertificateId": "12345678-1234-1234-1234-123456789012",
  "SignatureValue": "ZOyIygCyaOW6Gj****MlNKiuyjfzw=",
  "RequestId": "5979d897-d69f-4fc9-87dd-f3bb73c40b80"

Error codes

HTTP status code Error code Error message Description
404 Certificate.NotFound The specified certificate is not found. The error message returned because the specified certificate does not exist.

For a list of error codes, visit the API Error Center.