CreateKey

By default, CreateKey creates a symmetric encryption KMS key with key material that KMS generates. This is the basic and most widely used type of KMS key, and provides the best performance.

To create a symmetric encryption KMS key, you don't need to specify any parameters. The default value for KeySpec, SYMMETRIC_DEFAULT, the default value for KeyUsage, ENCRYPT_DECRYPT, and the default value for Origin, AWS_KMS, create a symmetric encryption KMS key with KMS key material.

If you need a key for basic encryption and decryption or you are creating a KMS key to protect your resources in an Amazon service, create a symmetric encryption KMS key. The key material in a symmetric encryption key never leaves Amazon KMS unencrypted. You can use a symmetric encryption KMS key to encrypt and decrypt data up to 4,096 bytes, but they are typically used to generate data keys and data keys pairs. For details, see GenerateDataKey and GenerateDataKeyPair.

To create an asymmetric KMS key, use the KeySpec parameter to specify the type of key material in the KMS key. Then, use the KeyUsage parameter to determine whether the KMS key will be used to encrypt and decrypt or sign and verify. You can't change these properties after the KMS key is created.

Asymmetric KMS keys contain an RSA key pair, Elliptic Curve (ECC) key pair, ML-DSA key pair or an SM2 key pair (China Regions only). The private key in an asymmetric KMS key never leaves Amazon KMS unencrypted. However, you can use the GetPublicKey operation to download the public key so it can be used outside of Amazon KMS. Each KMS key can have only one key usage. KMS keys with RSA key pairs can be used to encrypt and decrypt data or sign and verify messages (but not both). KMS keys with NIST-recommended ECC key pairs can be used to sign and verify messages or derive shared secrets (but not both). KMS keys with ECC_SECG_P256K1 can be used only to sign and verify messages. KMS keys with ML-DSA key pairs can be used to sign and verify messages. KMS keys with SM2 key pairs (China Regions only) can be used to either encrypt and decrypt data, sign and verify messages, or derive shared secrets (you must choose one key usage type). For information about asymmetric KMS keys, see Asymmetric KMS keys in the Amazon Key Management Service Developer Guide.

To create an HMAC KMS key, set the KeySpec parameter to a key spec value for HMAC KMS keys. Then set the KeyUsage parameter to GENERATE_VERIFY_MAC. You must set the key usage even though GENERATE_VERIFY_MAC is the only valid key usage value for HMAC KMS keys. You can't change these properties after the KMS key is created.

HMAC KMS keys are symmetric keys that never leave Amazon KMS unencrypted. You can use HMAC keys to generate (GenerateMac) and verify (VerifyMac) HMAC codes for messages up to 4096 bytes.

To create a multi-Region primary key in the local Amazon Web Services Region, use the MultiRegion parameter with a value of True. To create a multi-Region replica key, that is, a KMS key with the same key ID and key material as a primary key, but in a different Amazon Web Services Region, use the ReplicateKey operation. To change a replica key to a primary key, and its primary key to a replica key, use the UpdatePrimaryRegion operation.

You can create multi-Region KMS keys for all supported KMS key types: symmetric encryption KMS keys, HMAC KMS keys, asymmetric encryption KMS keys, and asymmetric signing KMS keys. You can also create multi-Region keys with imported key material. However, you can't create multi-Region keys in a custom key store.

This operation supports multi-Region keys, an Amazon KMS feature that lets you create multiple interoperable KMS keys in different Amazon Web Services Regions. Because these KMS keys have the same key ID, key material, and other metadata, you can use them interchangeably to encrypt data in one Amazon Web Services Region and decrypt it in a different Amazon Web Services Region without re-encrypting the data or making a cross-Region call. For more information about multi-Region keys, see Multi-Region keys in Amazon KMS in the Amazon Key Management Service Developer Guide.

To import your own key material into a KMS key, begin by creating a KMS key with no key material. To do this, use the Origin parameter of CreateKey with a value of EXTERNAL. Next, use GetParametersForImport operation to get a public key and import token. Use the wrapping public key to encrypt your key material. Then, use ImportKeyMaterial with your import token to import the key material. For step-by-step instructions, see Importing Key Material in the Amazon Key Management Service Developer Guide .

You can import key material into KMS keys of all supported KMS key types: symmetric encryption KMS keys, HMAC KMS keys, asymmetric encryption KMS keys, and asymmetric signing KMS keys. You can also create multi-Region keys with imported key material. However, you can't import key material into a KMS key in a custom key store.

To create a multi-Region primary key with imported key material, use the Origin parameter of CreateKey with a value of EXTERNAL and the MultiRegion parameter with a value of True. To create replicas of the multi-Region primary key, use the ReplicateKey operation. For instructions, see Importing key material step 1. For more information about multi-Region keys, see Multi-Region keys in Amazon KMS in the Amazon Key Management Service Developer Guide.

A custom key store lets you protect your Amazon resources using keys in a backing key store that you own and manage. When you request a cryptographic operation with a KMS key in a custom key store, the operation is performed in the backing key store using its cryptographic keys.

Amazon KMS supports Amazon CloudHSM key stores backed by an Amazon CloudHSM cluster and external key stores backed by an external key manager outside of Amazon. When you create a KMS key in an Amazon CloudHSM key store, Amazon KMS generates an encryption key in the Amazon CloudHSM cluster and associates it with the KMS key. When you create a KMS key in an external key store, you specify an existing encryption key in the external key manager.

Before you create a KMS key in a custom key store, the ConnectionState of the key store must be CONNECTED. To connect the custom key store, use the ConnectCustomKeyStore operation. To find the ConnectionState, use the DescribeCustomKeyStores operation.

To create a KMS key in a custom key store, use the CustomKeyStoreId. Use the default KeySpec value, SYMMETRIC_DEFAULT, and the default KeyUsage value, ENCRYPT_DECRYPT to create a symmetric encryption key. No other key type is supported in a custom key store.

To create a KMS key in an Amazon CloudHSM key store, use the Origin parameter with a value of AWS_CLOUDHSM. The Amazon CloudHSM cluster that is associated with the custom key store must have at least two active HSMs in different Availability Zones in the Amazon Region.

To create a KMS key in an external key store, use the Origin parameter with a value of EXTERNAL_KEY_STORE and an XksKeyId parameter that identifies an existing external key.

Skips ("bypasses") the key policy lockout safety check. The default value is false.

Use this parameter only when you intend to prevent the principal that is making the request from making a subsequent PutKeyPolicy request on the KMS key.

Type: Boolean

Required: No

This parameter has been deprecated.

Instead, use the KeySpec parameter.

The KeySpec and CustomerMasterKeySpec parameters work the same way. Only the names differ. We recommend that you use KeySpec parameter in your code. However, to avoid breaking changes, Amazon KMS supports both parameters.

Type: String

Valid Values: RSA_2048 | RSA_3072 | RSA_4096 | ECC_NIST_P256 | ECC_NIST_P384 | ECC_NIST_P521 | ECC_SECG_P256K1 | SYMMETRIC_DEFAULT | HMAC_224 | HMAC_256 | HMAC_384 | HMAC_512 | SM2

Required: No

Creates the KMS key in the specified custom key store. The ConnectionState of the custom key store must be CONNECTED. To find the CustomKeyStoreID and ConnectionState use the DescribeCustomKeyStores operation.

This parameter is valid only for symmetric encryption KMS keys in a single Region. You cannot create any other type of KMS key in a custom key store.

When you create a KMS key in an Amazon CloudHSM key store, Amazon KMS generates a non-exportable 256-bit symmetric key in its associated Amazon CloudHSM cluster and associates it with the KMS key. When you create a KMS key in an external key store, you must use the XksKeyId parameter to specify an external key that serves as key material for the KMS key.

Type: String

Length Constraints: Minimum length of 1. Maximum length of 64.

Required: No

A description of the KMS key. Use a description that helps you decide whether the KMS key is appropriate for a task. The default value is an empty string (no description).

To set or change the description after the key is created, use UpdateKeyDescription.

Type: String

Length Constraints: Minimum length of 0. Maximum length of 8192.

Required: No

Specifies the type of KMS key to create. The default value, SYMMETRIC_DEFAULT, creates a KMS key with a 256-bit AES-GCM key that is used for encryption and decryption, except in China Regions, where it creates a 128-bit symmetric key that uses SM4 encryption. For a detailed description of all supported key specs, see Key spec reference in the Amazon Key Management Service Developer Guide .

The KeySpec determines whether the KMS key contains a symmetric key or an asymmetric key pair. It also determines the algorithms that the KMS key supports. You can't change the KeySpec after the KMS key is created. To further restrict the algorithms that can be used with the KMS key, use a condition key in its key policy or IAM policy. For more information, see kms:EncryptionAlgorithm, kms:MacAlgorithm, kms:KeyAgreementAlgorithm, or kms:SigningAlgorithm in the Amazon Key Management Service Developer Guide .

Amazon KMS supports the following key specs for KMS keys:

Type: String

Valid Values: RSA_2048 | RSA_3072 | RSA_4096 | ECC_NIST_P256 | ECC_NIST_P384 | ECC_NIST_P521 | ECC_SECG_P256K1 | SYMMETRIC_DEFAULT | HMAC_224 | HMAC_256 | HMAC_384 | HMAC_512 | SM2 | ML_DSA_44 | ML_DSA_65 | ML_DSA_87

Required: No

Determines the cryptographic operations for which you can use the KMS key. The default value is ENCRYPT_DECRYPT. This parameter is optional when you are creating a symmetric encryption KMS key; otherwise, it is required. You can't change the KeyUsage value after the KMS key is created.

Select only one valid value.

Type: String

Valid Values: SIGN_VERIFY | ENCRYPT_DECRYPT | GENERATE_VERIFY_MAC | KEY_AGREEMENT

Required: No

Creates a multi-Region primary key that you can replicate into other Amazon Web Services Regions. You cannot change this value after you create the KMS key.

For a multi-Region key, set this parameter to True. For a single-Region KMS key, omit this parameter or set it to False. The default value is False.

This operation supports multi-Region keys, an Amazon KMS feature that lets you create multiple interoperable KMS keys in different Amazon Web Services Regions. Because these KMS keys have the same key ID, key material, and other metadata, you can use them interchangeably to encrypt data in one Amazon Web Services Region and decrypt it in a different Amazon Web Services Region without re-encrypting the data or making a cross-Region call. For more information about multi-Region keys, see Multi-Region keys in Amazon KMS in the Amazon Key Management Service Developer Guide.

This value creates a primary key, not a replica. To create a replica key, use the ReplicateKey operation.

You can create a symmetric or asymmetric multi-Region key, and you can create a multi-Region key with imported key material. However, you cannot create a multi-Region key in a custom key store.

Type: Boolean

Required: No

The source of the key material for the KMS key. You cannot change the origin after you create the KMS key. The default is AWS_KMS, which means that Amazon KMS creates the key material.

To create a KMS key with no key material (for imported key material), set this value to EXTERNAL. For more information about importing key material into Amazon KMS, see Importing Key Material in the Amazon Key Management Service Developer Guide. The EXTERNAL origin value is valid only for symmetric KMS keys.

To create a KMS key in an Amazon CloudHSM key store and create its key material in the associated Amazon CloudHSM cluster, set this value to AWS_CLOUDHSM. You must also use the CustomKeyStoreId parameter to identify the Amazon CloudHSM key store. The KeySpec value must be SYMMETRIC_DEFAULT.

To create a KMS key in an external key store, set this value to EXTERNAL_KEY_STORE. You must also use the CustomKeyStoreId parameter to identify the external key store and the XksKeyId parameter to identify the associated external key. The KeySpec value must be SYMMETRIC_DEFAULT.

Type: String

Valid Values: AWS_KMS | EXTERNAL | AWS_CLOUDHSM | EXTERNAL_KEY_STORE

Required: No

The key policy to attach to the KMS key.

If you provide a key policy, it must meet the following criteria:

If you do not provide a key policy, Amazon KMS attaches a default key policy to the KMS key. For more information, see Default key policy in the Amazon Key Management Service Developer Guide.

For help writing and formatting a JSON policy document, see the IAM JSON Policy Reference in the Amazon Identity and Access Management User Guide .

Type: String

Length Constraints: Minimum length of 1. Maximum length of 32768.

Pattern: [\u0009\u000A\u000D\u0020-\u00FF]+

Required: No

Assigns one or more tags to the KMS key. Use this parameter to tag the KMS key when it is created. To tag an existing KMS key, use the TagResource operation.

To use this parameter, you must have kms:TagResource permission in an IAM policy.

Each tag consists of a tag key and a tag value. Both the tag key and the tag value are required, but the tag value can be an empty (null) string. You cannot have more than one tag on a KMS key with the same tag key. If you specify an existing tag key with a different tag value, Amazon KMS replaces the current tag value with the specified one.

When you add tags to an Amazon resource, Amazon generates a cost allocation report with usage and costs aggregated by tags. Tags can also be used to control access to a KMS key. For details, see Tags in Amazon KMS.

Type: Array of Tag objects

Required: No

Identifies the external key that serves as key material for the KMS key in an external key store. Specify the ID that the external key store proxy uses to refer to the external key. For help, see the documentation for your external key store proxy.

This parameter is required for a KMS key with an Origin value of EXTERNAL_KEY_STORE. It is not valid for KMS keys with any other Origin value.

The external key must be an existing 256-bit AES symmetric encryption key hosted outside of Amazon in an external key manager associated with the external key store specified by the CustomKeyStoreId parameter. This key must be enabled and configured to perform encryption and decryption. Each KMS key in an external key store must use a different external key. For details, see Requirements for a KMS key in an external key store in the Amazon Key Management Service Developer Guide.

Each KMS key in an external key store is associated two backing keys. One is key material that Amazon KMS generates. The other is the external key specified by this parameter. When you use the KMS key in an external key store to encrypt data, the encryption operation is performed first by Amazon KMS using the Amazon KMS key material, and then by the external key manager using the specified external key, a process known as double encryption. For details, see Double encryption in the Amazon Key Management Service Developer Guide.

Type: String

Length Constraints: Minimum length of 1. Maximum length of 128.

Pattern: ^[a-zA-Z0-9-_.]+$

Required: No

Metadata associated with the KMS key.

Type: KeyMetadata object

The request was rejected because the associated Amazon CloudHSM cluster did not meet the configuration requirements for an Amazon CloudHSM key store.

For information about the requirements for an Amazon CloudHSM cluster that is associated with an Amazon CloudHSM key store, see Assemble the Prerequisites in the Amazon Key Management Service Developer Guide. For information about creating a private subnet for an Amazon CloudHSM cluster, see Create a Private Subnet in the Amazon CloudHSM User Guide. For information about cluster security groups, see Configure a Default Security Group in the Amazon CloudHSM User Guide .

HTTP Status Code: 400

The request was rejected because of the ConnectionState of the custom key store. To get the ConnectionState of a custom key store, use the DescribeCustomKeyStores operation.

This exception is thrown under the following conditions:

HTTP Status Code: 400

The request was rejected because Amazon KMS cannot find a custom key store with the specified key store name or ID.

HTTP Status Code: 400

The system timed out while trying to fulfill the request. You can retry the request.

HTTP Status Code: 500

The request was rejected because a specified ARN, or an ARN in a key policy, is not valid.

HTTP Status Code: 400

The request was rejected because an internal exception occurred. The request can be retried.

HTTP Status Code: 500

The request was rejected because a length constraint or quota was exceeded. For more information, see Quotas in the Amazon Key Management Service Developer Guide.

HTTP Status Code: 400

The request was rejected because the specified policy is not syntactically or semantically correct.

HTTP Status Code: 400

The request was rejected because one or more tags are not valid.

HTTP Status Code: 400

The request was rejected because a specified parameter is not supported or a specified resource is not valid for this operation.

HTTP Status Code: 400

The request was rejected because the (XksKeyId) is already associated with another KMS key in this external key store. Each KMS key in an external key store must be associated with a different external key.

HTTP Status Code: 400

The request was rejected because the external key specified by the XksKeyId parameter did not meet the configuration requirements for an external key store.

The external key must be an AES-256 symmetric key that is enabled and performs encryption and decryption.

HTTP Status Code: 400

The request was rejected because the external key store proxy could not find the external key. This exception is thrown when the value of the XksKeyId parameter doesn't identify a key in the external key manager associated with the external key proxy.

Verify that the XksKeyId represents an existing key in the external key manager. Use the key identifier that the external key store proxy uses to identify the key. For details, see the documentation provided with your external key store proxy or key manager.

HTTP Status Code: 400