Creates a customer master key (CMK).

Usage notes

A CMK can be symmetric or asymmetric. Symmetric CMKs are used to generate data keys that can be used to encrypt large amounts of data. You can also use symmetric CMKs to encrypt less than 6 KB of data. For more information, see GenerateDataKey. Asymmetric CMKs are used to encrypt data, decrypt data, generate digital signatures, and verify digital signatures. However, you cannot use asymmetric CMKs to generate data keys.

The following table describes different types of CMKs and the operations that are supported by the CMKs.

CMK category

CMK type

Description

Encryption and decryption

Signature generation and verification

Symmetric CMK

Aliyun_AES_256

An advanced Encryption Standard (AES) key with a length of 256 bits.

Supported

Not supported

Symmetric CMK

Aliyun_AES_128

An AES key with a length of 128 bits. Only Dedicated KMS supports this CMK type.

Supported

Not supported

Symmetric CMK

Aliyun_AES_192

An AES key with a length of 192 bits. Only Dedicated KMS supports this CMK type.

Supported

Not supported

Symmetric CMK

Aliyun_SM4

SM4 key.

Supported

Not supported

Asymmetric CMK

RSA_2048

A Rivest-Shamir-Adleman (RSA) key with a length of 2,048 bits.

Supported

Supported

Asymmetric CMK

RSA_3072

A RSA key with a length of 3,072 bits.

Supported

Supported

Asymmetric CMK

EC_P256

National Institute of Standards and Technology (NIST) P-256 (secp256r1) .

Not supported

Supported

Asymmetric CMK

EC_P256K

Standards for Efficient Cryptography Group (SECG) elliptic curve secp256k1.

Not supported

Supported

Asymmetric CMK

EC_SM2

256-bit elliptic curve over the prime field that is defined in GB/T 32918.

Supported

Supported

Note
  • If the value of the KeySpec parameter that is used to create a symmetric CMK is prefixed with Aliyun_, a standard cryptographic algorithm is used, but non-standard ciphertext is generated. An asymmetric CMK can be used to generate standard ciphertext or signatures.
  • You can use an RSA CMK to perform one of the two types of operations: encrypt and decrypt data, and generate and verify signatures. You cannot use the RSA CMK to perform both two types of operations.

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 CreateKey

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

Description String No key description example

The description of the CMK.

The description can be 0 to 8,192 characters in length.

KeySpec String No Aliyun_AES_256

The type of the CMK. Valid values:

  • Aliyun_AES_256
  • Aliyun_AES_128
  • Aliyun_AES_192
  • Aliyun_SM4
  • RSA_2048
  • RSA_3072
  • EC_P256
  • EC_P256K
  • EC_SM2
Note
  • The default type of the CMK is Aliyun_AES_256.

  • Only Dedicated KMS supports Aliyun_AES_128 and Aliyun_AES_192.
KeyUsage String No ENCRYPT/DECRYPT

The usage of the CMK. Valid values:

  • ENCRYPT/DECRYPT: encrypts or decrypts data.
  • SIGN/VERIFY: generates or verifies a digital signature.
Origin String No Aliyun_KMS

The source of key material. Valid values:

  • Aliyun_KMS (default value)
  • EXTERNAL
Note
  • The value of this parameter is case-sensitive.
  • If you set the KeySpec parameter to an asymmetric CMK type, you are not allowed to set the Origin parameter to EXTERNAL.
  • If you set the Origin parameter to EXTERNAL, you must import key material. For more information, see Import key material.
ProtectionLevel String No SOFTWARE

The protection level of the CMK. Valid values:

  • SOFTWARE (default value)
  • HSM
Note
  • The value of this parameter is case-sensitive.
  • Assume that you set this parameter to HSM. If you set the Origin parameter to Aliyun_KMS, the CMK is created in a managed hardware security module (HSM). If you set the Origin parameter to EXTERNAL, you can import an external key to the managed HSM.
EnableAutomaticRotation Boolean No false

Specifies whether to enable automatic key rotation. Valid values:

  • true
  • false (default value)
Note If you set the Origin parameter to EXTERNAL or the KeySpec parameter to an asymmetric CMK type, automatic key rotation is unavailable.
RotationInterval String No 365d

The interval for automatic key rotation. Specify the value in the integer[unit] format. The following units are supported: d (day), h (hour), m (minute), and s (second). For example, you can use either 7d or 604800s to specify a seven-day interval. The interval can range from 7 days to 730 days.

Note If you set the EnableAutomaticRotation parameter to true, you must also specify this parameter. If you set the EnableAutomaticRotation parameter to false, you can leave this parameter unspecified.

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

Response parameters

Parameter Type Example Description
KeyMetadata Struct

The metadata of the CMK.

Arn String acs:kms:cn-qingdao:154035569884****:key/d6bee1cb-2e14-4277-ba6b-73786b21****

The Alibaba Cloud Resource Name (ARN) of the CMK.

AutomaticRotation String Disabled

Indicates whether automatic key rotation is enabled. Valid values:

  • Enabled: Automatic key rotation is enabled.
  • Disabled: Automatic key rotation is disabled.
  • Suspended: Automatic key rotation is suspended. For more information, see Automatic key rotation.
Note Automatic key rotation is available only for symmetric CMKs.
CreationDate String 2016-03-25T10:42:40Z

The time when the CMK was created. The time is displayed in UTC.

Creator String 154035569884****

The creator of the CMK.

DeleteDate String 2020-07-06T18:22:03Z

The time when the CMK is scheduled for deletion.

For more information, see ScheduleKeyDeletion.

Note This value is returned only when the value of the KeyState parameter is PendingDeletion.
Description String key description example

The description of the CMK.

KeyId String d6bee1cb-2e14-4277-ba6b-73786b21****

The ID of the CMK. The ID is globally unique.

KeySpec String Aliyun_AES_256

The type of the CMK.

KeyState String Enabled

The status of the CMK.

For more information, see Impact of CMK status on API operations.

KeyUsage String ENCRYPT/DECRYPT

The usage of the CMK.

LastRotationDate String 2019-06-06T18:22:03Z

The time when the last rotation was performed. The time is displayed in UTC.

For a new CMK, the value of this parameter is the time when the initial version of the CMK was generated.

MaterialExpireTime String 2020-07-06T18:22:03Z

The time when the key material for the CMK expires. The time is displayed in UTC.

If the parameter is empty, the key material of the CMK does not expire.

NextRotationDate String 2020-07-06T18:22:03Z

The time when the next rotation will be performed.

Note This value is returned only when the value of the AutomaticRotation parameter is Enabled or Suspended.
Origin String Aliyun_KMS

The source of the key material for the CMK.

PrimaryKeyVersion String 7ce1d081-06cb-42e6-aab6-5c5de030****

The ID of the primary key version of the symmetric CMK.

Note
  • The primary key version of a symmetric CMK is an active encryption key. KMS uses the primary key version of a specified CMK to encrypt data.
  • This parameter is unavailable for asymmetric CMKs.
ProtectionLevel String SOFTWARE

The protection level of the CMK.

RotationInterval String 31536000s

The period of automatic key rotation. Unit: seconds. The value is in the format of an integer followed by the letter s. For example, if the rotation period is seven days, this parameter is set to 604800s. This value is returned only when the value of the AutomaticRotation parameter is Enabled or Suspended.

RequestId String 36c7e41a-3f2c-45f7-9bdd-d1dc1e7e7e06

The ID of the request.

Examples

Sample requests

https://[Endpoint]/?Action=CreateKey
&<Common request parameters>

Sample success responses

XML format

<KMS>
      <KeyMetadata>
            <CreationDate>2021-04-12T06:00:54Z</CreationDate>
            <Description></Description>
            <KeyId>d6bee1cb-2e14-4277-ba6b-73786b21****</KeyId>
            <KeySpec>Aliyun_AES_256</KeySpec>
            <KeyState>Enabled</KeyState>
            <KeyUsage>ENCRYPT/DECRYPT</KeyUsage>
            <PrimaryKeyVersion>7ce1d081-06cb-42e6-aab6-5c5de030****</PrimaryKeyVersion>
            <DeleteDate></DeleteDate>
            <Creator>154035569884****</Creator>
            <Arn>acs:kms:cn-qingdao:154035569884****:key/d6bee1cb-2e14-4277-ba6b-73786b21****</Arn>
            <Origin>Aliyun_KMS</Origin>
            <MaterialExpireTime></MaterialExpireTime>
            <ProtectionLevel>SOFTWARE</ProtectionLevel>
            <LastRotationDate>2021-04-12T06:00:54Z</LastRotationDate>
            <AutomaticRotation>Disabled</AutomaticRotation>
      </KeyMetadata>
      <RequestId>36c7e41a-3f2c-45f7-9bdd-d1dc1e7e7e06</RequestId>
</KMS>

JSON format

{
  "KeyMetadata": {
    "CreationDate": "2021-04-12T06:00:54Z",
    "Description": "",
    "KeyId": "d6bee1cb-2e14-4277-ba6b-73786b21****",
    "KeySpec": "Aliyun_AES_256",
    "KeyState": "Enabled",
    "KeyUsage": "ENCRYPT/DECRYPT",
    "PrimaryKeyVersion": "7ce1d081-06cb-42e6-aab6-5c5de030****",
    "DeleteDate": "",
    "Creator": "154035569884****",
    "Arn": "acs:kms:cn-qingdao:154035569884****:key/d6bee1cb-2e14-4277-ba6b-73786b21****",
    "Origin": "Aliyun_KMS",
    "MaterialExpireTime": "",
    "ProtectionLevel": "SOFTWARE",
    "LastRotationDate": "2021-04-12T06:00:54Z",
    "AutomaticRotation": "Disabled"
  },
  "RequestId": "36c7e41a-3f2c-45f7-9bdd-d1dc1e7e7e06"
}

Error codes

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